ALBERT

Description: Leftovers are particularly at risk of being discarded, and therefore a main component of household food waste. This study provides insights into sources of heterogeneity in leftover management behaviours, with a particular focus on the use of meal kits providing matched portion and ingredient sizes, and identifies consumer segments via a latent class analysis. We investigate whether belonging to a segment with positive attitudes toward leftovers, and engagement in conscious leftover management behaviours decreases the amounts of dinner leftovers and food waste. Besides, we demonstrate that several food waste antecedents, emotions, personal norms, intention and dinner procurement routines elicit leftover management segment membership. In addition to examining such individual differences, we also investigate the role of meal-level determinants, in particular, whether meal kits heterogeneously affect dinner leftovers depending on the consumer's leftover management segment. Data was collected from 868 households from six countries, using an online survey and diaries. Results of the latent class analysis point towards five consumer segments. We found differences in dinner leftovers amount across classes and detected heterogeneous effects of meal kits. That is, meal kits were able to diminish leftovers in two segments, but not in the other segments. These results provide novel insights into consumer heterogeneity regarding the occurrence, antecedents, and potential solutions of leftovers and resulting household food waste. Implications for both theory and policy are discussed.

Description: As the climate crisis is accelerating and the pressure to act is steadily increasing, many companies are claiming themselves or their products carbon neutral. This is usually achieved by offsetting residual emissions with carbon certificates (carbon offsetting). However, recent revelations about the inadequate quality of carbon credits and legal uncertainties surrounding the use of such offset claims are increasingly raising doubts about this approach. This Wuppertal Report examines how the EU can promote integrity in corporate climate action. Taking into account the new framework of the Paris Agreement, the paper outlines various options for how the EU could push for more integrity and effectively combat greenwashing through the targeted use of Article 6 of the Paris Agreement. In their recommendations, the authors advocate addressing the most serious consequences of ongoing offset practices through increased regulation of offset claims. If a ban on offset claims cannot be implemented, claims requirements and carbon offset regulations should be further specified, for example, by prohibiting any type of double counting of emissions reductions. In addition to tightening the rules for corporate offset claims within Europe, the EU could help partner countries make informed decisions when approving climate change mitigation measures and respective carbon credits. The report also emphasizes the EU's special role in international climate negotiations, where it should advocate for a strong legal framework for climate action under Article 6.

Description: The rise of pedal-assisted bicycles (e-bikes) has the potential to contribute to reducing ubiquitous automobility and its negative externalities on the global climate, mobility justice and the quality of urban life. But what makes this new practice so successful in recruiting new practitioners? What policies can ensure that e-bikes are used in a wide range of situations, thus substituting as much car driving as possible - or even reducing the number of cars? The study focuses on commuting as this use case frequently entails the main obstacles to e-biking in daily routines (e.g., sweat, weather, transporting children or goods). The analysis is primarily based on interviews with practitioners and initially provides a thorough depiction of the practice elements (meanings, materials and competences) involved in e-bike commuting. It furthermore elicits key drivers of and barriers to daily e-bike commuting, points to a number of elements that are important to overcome these barriers and develops two tangible policy approaches to foster the substitution of e-biking for car driving.

Description: The production of green hydrogen in Germany is more competitive than expected compared to imports. This is the key finding of a meta-analysis conducted by the Wuppertal Institute on behalf of the North Rhine-Westphalia Association for Renewable Energies (Landesverband Erneuerbare Energien NRW). The hydrogen study focuses primarily on the year 2030 and beyond - and confirms the advantages of green hydrogen produced in Germany from domestic renewable energies, especially when the evaluation is viewed from a holistic system perspective.

Description: As investors and financial intermediaries, private banks are increasingly confronted with climate change concerns. But to what extent do banks identify as the changemakers driving climate alignment forward? To advance this question, this paper analyzes the South African banking sector with a specific focus on Standard Bank and Nedbank as exemplary case studies. Relying on the concept of "climate mainstreaming", we critically assess the banks' annual reports and compare their self-portrayal with publicly available sources on the bank's business practices, chiefly provided by non-governmental organizations and media. We find that Nedbank pushes a holistic narrative of climate change as an inevitable business opportunity. Standard Bank, in turn, relies on a "narrative of balance" between climate change and other profit-oriented investments to safeguard its stakes in the fossil industry. In so doing, this paper sheds light on greenwashing practices within disclosure specifically and the lack of binding corporate regulation more generally.

Description: Most air-conditioned buildings in India operate as Mixed-Mode Buildings (MMBs), either fully air-conditioned or with natural ventilation depending on the weather. Energy consumption for space cooling is a vital end-use service in buildings. Air-conditioning is expected to increase significantly due to high growth estimates in building construction, sales of Room Air-Conditioners (RACs), and real income growth. Therefore, this thesis examines the most influential design and control parameters that influence the potential of MMBs in India in relation to their thermal and energy performance. The primary features of MMBs analysed in the research project are as follows: shutting windows at night makes night ventilation redundant; natural ventilation through ceiling fans and windows is utilised to maintain optimal thermal conditions in naturally-ventilated mode and RACs are employed in air-conditioned mode. This thesis poses three research questions and aims to answer them. Firstly, what are the research gaps in assessing thermal and energy performance in mixed-mode buildings in India? Secondly, what is their potential concerning key operating conditions, and which parameters affect this potential? Lastly, how can these influential parameters be optimised? To answer these questions, three research methods were employed: 1) literature review; 2) large-scale simulation of building energy performance combined with uncertainty and sensitivity analysis; and 3) field studies of user behaviour with regards to RACs and the impact of ceiling fans and RACs on indoor conditions and energy consumption. The study identifies the cooling set point temperature as the most influential control parameter. In general, input parameters related to building design, shape and geometry were considered more important than those related to construction parameters. Furthermore, the study highlights that a set point temperature of 28 or 30°C is sufficient to maintain indoor comfort according to the Indian Model for Adaptive Comfort (IMAC) for residential buildings. If a specific airflow is required, it would use the least energy to run the ceiling fan at a low speed, usually set at 1.

Description: The COVID-19 pandemic has jolted societies out of normality, possibly creating new conditions for sustainability transformations. What does this mean for sustainability research? Because of the scope of the crisis, researchers have been heavily involved: not only have they had to speed up the pace of scientific production to provide urgently needed COVID-19 knowledge, but they have also been affected citizens. For sustainability science, this calls for an experience-based reflection on the positionality and orientation of research aiming to support sustainability transformations. Twenty sustainability researchers discussed their sustainability research on COVID-19 in three workshops based on the following questions: How does the pandemic - and the measures taken to deal with it - affect sustainable development? What can we learn from the pandemic from the perspective of societal transformation? The present discussion paper emerged from this multidisciplinary exchange among sustainability researchers, considering five topics: impacts of the COVID-19 crisis on sustainability transformations; learning for sustainability transformations; the role of solidarity; governance and political steering; and the role of science in society. Our discussions led to a meta-level reflection on what sustainability research can learn from research on COVID-19 regarding topics and disciplinary angles, time dimensions, the role of researchers, and how adequate preparation for both crises and long-term transformations requires interdisciplinary interaction.

Description: The transition to a greener and more circular economy has been a European policy priority for several years. The Circular Economy Action Plan of 2020 underlines the ambition. The following EEA initiatives are meant to support the transition process: - Bellagio Process on circular economy monitoring principles (EPA network); - Enhancement of EEA indicators on circular economy (ETC/WMGE); - Explorative work on novel data streams (FWC); - Co-creation work - knowledge sharing of monitoring experience (ETC/Eionet). The scope of the present task was to report on the co-creation process that was undertaken at the end of 2020. The co-creation process was organised to identify: (i) best practices on monitoring strategies, data sources and target setting; and (ii) areas of circularity measuring and monitoring that remain challenging and require additional investment. The co-creation process partially built on the work done during the Bellagio Process/Initiative which was run in parallel. This ETC report presents and documents the evidence gathered throughout the co- creation process as well as providing a retrospective analysis of the links to the Bellagio Principles.

Description: "Sustainable Development" can be understood as a widely used discourse that has become even more prominent since the publication of the UN Agenda 2030 for Sustainable Development in 2015. In this paper we analyze the way sustainable development discourse unfolds within the context of development aid in Germany by undertaking a discourse analysis of reports on development policy published 1973-2017 by the German Federal Ministry for Economic Cooperation and Development. Our analysis reveals that the sustainable development discourse is characterized by distinct components and storylines that change over time. We detect, in general, a shift away from a focus on environmental protection toward an emphasis on the role of the private sector in leading sustainable development. We argue, therefore, that although development is now only legitimate if it is "sustainable", the discourse apparently facilitates the uneven allocation of development aid. The concern that arises here is that although Agenda 2030 pledges to take "bold and transformative steps" to secure the planet and to leave "no one behind" the least developed states who cannot provide "private sector opportunities" or fulfil "national self-responsibilities" for sustainable development are indeed being "left behind".

Description: Since the introduction of Germany's first Thermal Insulation Ordinance in the 1970s in response to the oil crisis, requirements for the energy performance of buildings have consistently increased. Today, these are ruled by the German Building Energy Act, which is currently being amended. Despite this continuous tightening of regulations, the energy consumption in German housing has hardly decreased. The continuous increase in residential space per person is a significant reason for this.

Description: The objectives of the urban mobility transition have been clearly set out: gaining more space for urban living, reducing noise and emissions that have a negative impact on the climate and improving air quality. That means less traffic in cities and more trips made using environmentally-friendly modes of transport - i.e., walking, cycling or foot scooters or public transport. In transport policy, the focus is generally on innovative approaches to shaping the mobility transition. This paper aims to explain the concept of exnovation in the context of the urban mobility transition and to underpin it using specific practical examples. In the course of this process, it is intended to identify the obstacles that stand in the way of rolling out the concept on an area-wide basis in order to deduce strategies and courses of action for expanding the concept in the future.

Description: In his essay, the author presents a stock-taking of the debate on Green Deals. The starting point of this personal assessment is a brief outline of the content and impact of a study in which the author and colleagues published a first outline of a "Green New Deal for Europe" as a political response to the 2008 financial crisis. 2008 had been a critical juncture for mainstream economics: however, from the perspective of policy-learning, the period after has been a lost decade. The European Green Deal as presented by the European Commission in 2019 can be perceived as a historic milestone and confirmation of a regime change in mainstream economic policy in which ecological considerations gain in importance. Yet, the Deal suffers from major deficits. In sum, the European Green Deal could be interpreted as an insufficient attempt to take advantage of the rapidly closing windows of opportunity for a peaceful transition towards sustainability. On the eve of a planetary crisis, the governance of economic transitions towards sustainability needs to be improved and accelerated. Reflecting on the 2009 study A Green New Deal for Europe, this essay attempts to draw a few lessons and frugal heuristics for the policy-design of Green Deals.

Description: The food system faces a multitude of challenges, including high greenhouse gas emissions, threats to biodiversity, increased diet-related diseases due to unbalanced diets, and socially problematic complex supply chains. This requires not only a transformation of the agricultural economy but also a change in the diet and lifestyles of all consumers. Developing and using digital and technological innovations can help to solve these challenges. In this context, the study provides impulses on how digitalisation can contribute to transforming production and consumption and which prerequisites have to be given to achieve this. The study describes the approaches for digitalisation along the value chain. These include optimising the use of resources in agriculture - for example with the help of smart farming - and supporting consumers with digital tools and assistance systems - such as apps designed to support grocery shopping. In addition, new business models and a better connection between production and consumption processes are also possible. This includes, for example, new digital sales channels or tracking and communicating sustainability indicators such as CO2 emissions across all steps of the value chain in order to enable all stakeholders to take reliable action.

Description: The ecological challenges of this decade have been clearly identified. The pressure of problems is increasing drastically; progress in climate protection or the preservation of biodiversity is insufficient. Little time is left to act. In consequence, we can only achieve and permanently secure social and environmental prosperity through far-reaching changes in economy and society. As a socio-technical innovation, digitalisation can realise its full ecological potential above all where it helps to profoundly change today's lifestyles, consumption patterns, and economic practices with a clear commitment to sustainability. As the most urgent design task of the 21st century, it is important to put digitalisation's enormous creative power at the service of the great transformation. The "great transformation" refers to the comprehensive restructuring of technology, the economy, and society in order to deal with the social and ecological challenges of the 21st century. This is a task for state action in terms of both regulatory policy orientation and facilitating collective processes of change - new tasks call for new governance. A digital-ecological statecraft is the indispensable prerequisite for effective state action to shape the social-ecological digital transformation. Using the example of the platform economy, we explore challenges, starting points, and (policy) measures.

Description: In the energy sector, few topics, if any, are more hyped than hydrogen. Countries develop hydrogen strategies to provide a perspective for hydrogen production and use in order to meet climate-neutrality goals. However, in this topical field the role of water is less accentuated. Hence, in this study, we seek to map the interrelations between the water and wastewater sector on the one hand and the hydrogen sector on the other hand, before reflecting upon our findings in a country case study. We chose the Hashemite Kingdom of Jordan because (i) hydrogen is politically discussed not least due to its high potentials for solar PV, and (ii) Jordan is water stressed - definitely a bad precondition for water-splitting electrolyzers. This research is based on a project called the German-Jordanian Water-Hydrogen-Dialogue (GJWHD), which started with comprehensive desk research mostly to map the intersectoral relations and to scope the situation in Jordan. Then, we carried out two expert workshops in Wuppertal, Germany, and Amman, Jordan, in order to further discuss the nexus by inviting a diverse set of stakeholders. The mapping exercise shows various options for hydrogen production and opportunities for planning hydrogen projects in water-scarce contexts such as Jordan.

Description: The Digital Product Passport (DPP) is a concept for collecting and sharing product-related information along the life cycle of a product. DPPs are currently the subject of intense discussion, and various development efforts are being undertaken. These are supported by regulatory activities, especially in the case of the battery passport. The aggregation of product life-cycle data and their respective use, as well as the sharing of these data between companies, entrepreneurs, and other actors in the value chain, is crucial for the creation of a resource-efficient circular economy. Despite the urgent need for such a solution, there is currently little attention given to the digital infrastructure for the creation and handling of the DPPs (i.e., the so-called DPP system). Moreover, there is so far no common understanding of what the requirements for a DPP system are. This is the background and underlying motivation of our paper: we identify the requirements for a DPP system in a structured way, i.e., based on stakeholder involvement and current literature from science and industry. In addition, we compose, categorize, and critically analyze the results, i.e., the list of requirements for DPP systems, in order to identify gaps. Summarized, our research provides insights into the criteria to be considered in the creation of an actual DPP system.

Description: To date, the circular economy has fallen short of its promise to reduce our resource demand and transform our production and consumption system. One key problem is the lack of understanding that highly promising strategies such as refuse, rethink, and reduce can be properly addressed using research on sufficiency. This article argues that a shift in focus is required in research and policy development from consumers who buy and handle circularly designed products to consumption patterns that follow the logic of sufficiency and explain how sufficiency-oriented concepts can be incorporated into existing social practices. The authors show that sufficiency is not necessarily as radical and unattractive as is often claimed, making it a suitable yet underrated strategy for sustainability and the transition to an effective circular economy. The case of urban gardening shows that small interventions can have far-reaching effects and transform consumption patterns as the logic of availability is contested by newly developed concepts of "enoughness" and opposition to "über-availability." The authors propose utilizing comprehensive state-of-the-art theories of consumption and human action when developing strategies and policies to make the circular economy sustainable while being more critical of utilitarian approaches. Using social practice theories that have proven to be beneficial allows human actions to be comprehensively analyzed by recognizing their embeddedness in social and material frameworks; addressing the meaning, competences, and materials of routinized human behavior; and examining indirect effects.

Description: The number of motorcycle taxis has soared in East African cities over the last decades, filling a gap in mobility needs while providing revenue opportunities to drivers. However, poor road safety combined with contribution to carbon emissions and air pollution creates a sustainability conundrum, which has led governments to control or repress the mode, yet without much success. After reviewing the characteristics and regulation of motorcycle taxis in Nairobi, Kigali, and Kampala, this study investigates the existence and impacts of two recent trends: digitalization and electrification. A comprehensive approach is adopted with a systematic review of the literature and policies, completed by field research and key informant interviews. We find out that electrification is mostly associated with positive impacts covering a spectrum of environment, economics, health, and social-related benefits, while the benefits of digitalization are more uncertain or contested. Impacts are however limited for both at the time of study as digitalization is highly volatile and electrification nascent. In conclusion, the paper identifies an interlinkage between the trends via the example of data, and further key research needs.

Description: In view of the accelerating climate crisis, the Russian invasion of Ukraine highlighted the dependency of fossil fuels on the part of Germany and the European Union (EU). With the priority aim to reduce the import dependency from the Russian Federation while providing energy security and staying on track with climate mitigation efforts, the Federal Government was presented with major challenges. Prior to the war, an approximate 34% of the mineral oil, 53.6% of the natural gas, and 50% of hard coal supplies to Germany originated from Russian sources. As of 2023, however, Germany is independent from Russian energy imports. This paper examines implications of the global energy crisis induced by the invasion on the energy sector in Germany. As a basis for achieving this analysis, a short overview of the energy situation in the country before the war and a demonstration of the provisional conditions is presented. This is followed by an analysis of the main consequences of the war and medium and long-term strategies to reach Germany's climate goals while maintaining energy security. Lastly, foreseeable consequences regarding the European and German climate goals are discussed.

Description: The current, private car-based mobility system is not sustainable: it contributes to climate change, it is unjust from gender- and socio-economic perspectives, endangers health and obstructs urban space. To counteract this, mobility data offers entirely new avenues for planning, organizing, and implementing mobility and transport. This strategy paper considers two possible ways to use mobility data for improving environmental sustainability and equitable access to transportation in Germany.

Description: The word "literacy" has come to be used to describe a wide range of competencies, including design literacy - a term that, despite its presence in design discourse, is still characterised by a certain fuzziness. In this paper, we explore this highly discursive theoretical field in order to gain a more nuanced and expanded understanding of the topic. In doing so, we argue that these divergent positions are also due to the ambiguity of the term “design”. We understand design as the perpetual de- and reconstruction of the world, as a way of worldmaking, both physically and conceptually. Thus, design literacy can be understood as a way to perceive traces of design and its processes, to perceive the world as contingent: a circular cognitive process of recognising that something - if not everything - in our cultural pluriverse is designed, understanding how it was designed and that it can potentially become the subject of design again and again. In our paper, we emphasise the contingency of design - and the ethical level that can arise from understanding the possibility of a different design. Ultimately, our aim with this paper is to emphasise that design literacy is a crucial competence for encouraging pluralistic perspectives and initiating transition processes, as it helps to acknowledge the temporary necessity but long-term non-necessity of things (which particularly includes the transitory nature of one's own creations).

Description: 22 years are left until the German target for climate neutrality should be reached. For the industrial sector, this implies a fundamental change and an acceleration of emission reduction, as from 2000 to 2021 the sector has reduced its greenhouse gas (GHG) emissions by only 13% (ERK, 2022). For the large structures, plants and assets that are characteristic for the energy intensive industrial sectors, the timespan implies no room for delay. One sector facing particular challenges is the chemical industry. Here, fossil resources are used not only for energetic purposes but for feedstock as well, in the petrochemical industry in particular. The efforts made in the petrochemical sector thereby not only affects the sectors own emissions, but the chemicals value chain at large, including the management of end-of-life products. The dependency on energetic resources for material use also means that there is a particular connection from the chemical industry to the energy system at large, which also entails special consideration. The chemical industry also has a particular relevance to the Antwerp-Rotterdam-Rhine-Ruhr-Area (ARRRA) which hosts several large petrochemical clusters in Germany as well as the Netherlands and Belgium, with complexly interlinked production chains. In reaching the climate targets, these regions especially face significant changes and may have the opportunity to position themselves as frontrunners for industrial transformation. That is, if a successful strategy can be found. In the recent years, numerous scenario analyses and roadmaps have been released drawing out pathways for chemical industries to develop in line with national and international climate targets. This can entail mapping of technological options, important prerequisites, particular challenges as well as important opportunities and timeframes. This meta-analysis summarizes and compares the findings of some of the most recent previous works at the national, European and global level. As the goal is to investigate the various strategic options and development paths for Germany and the ARRRA, it has a particular focus on roadmaps for Germany, the Netherlands and Belgium. It takes a quantitative as well as qualitative approach, looking both at resource and production volumes, different emission reduction strategies relative importance, as well as policy recommendations and other important framework conditions. A particular focus is put on the use of non-fossil feedstocks to reduce emissions.

Description: The EU Horizon 2020 project HiEff-BioPower (grant agreement No 727330, duration: 10/2016 - 09/2021) aimed at the development of a new, innovative, fuel flexible and highly efficient biomass CHP technology for a capacity range of 1 to 10 MW total energy output, suitable e.g. for on-site generation at larger residential apartment buildings or local heat grids. The new technology shall define a new milestone in terms of CHP efficiency and contribute to a sustainable energy supply based on renewable energies using otherwise unused residual biomass. It consists of a fuel-flexible updraft gasification technology with ultra-low particulate matter emissions, an integrated gas cleaning system and a solid oxide fuel cell (SOFC). The technology shall be applicable for a wide fuel spectrum for residual biomass (wood pellets, wood chips or selected agricultural fuels like agro-pellets) and achieve high gross electric (40%) and overall (90%) efficiencies as well as almost zero gaseous and particulate matter (PM) emissions (close or below the level of detection) as non-energy benefits. At the end of the project, final technology data has become available, as well as techno-economic analyses and market studies. Based on this data, this paper presents final results from the environmental impact assessment of the new HiEff-BioPower technology.

Description: The adoption of the Paris Agreement in 2015 and the passing of the Climate Action Law in Germany in 2019 established the legal need for the basic material industry in Germany to decarbonise. For the industry sector, the target is sets at a 49-51% GHG reduction by 2030 compared to 1990. Even though the sector specific targets are likely to become obsolete, a Hydrogen Strategy, Industry Strategy and Climate Protection Contracts are currently being developed or elaborated on. These are to further ensure and enable the basic material industry in Germany to decarbonise. These developments are emphasising the relevance of studying the industry decarbonisation at the time of conducting this research. As the institutionalisation of the industry decarbonisation is influenced by discourse, the analysis of the discourse is an important tool for studying the power effects produced by and built into the discourse. This is the first research aiming to provide a structured analysis of the discourse on industry decarbonisation in Germany. Drawing on discourse analysis and the Multilevel-Perspectives framework, this research investigated the power and dominance of storylines to influence the discourse of the industry transformation towards decarbonisation. In this research insights were obtained into the storylines used in this discourse, the actors who are part of this discourse, the frequency of storylines used and the percentage of actors making use of these storylines. Additionally, insights were generated into the discursive network and potential coalitions. This research made use of the Discourse Network Analysis software in combination with Visone and Excel for data collection, analysis, and visualisation. Based on 117 documents of various categories from the years 2012 to 2023, the discourse on German industry decarbonisation is discovered to be dominated by storylines of mainly technological or economic nature. The general sentiment discovered by the different actors is positive with the storylines focusing on establishing the conditions for the industry to decarbonise and no resistance being communicated. The discourse is furthermore dominated by most storylines. 18 out of 27 storylines are being used by more than 56% of all actors. The high overlap in storyline indicates discursive homogeneity. The homogeneity is further indicated through the lack of emerging discourse coalitions and the therewith connected lack of struggles for discursive dominance. One coalition can be defined with some actors being deeper involved and some being less involved in the discourse. As decisions on the transition path for Germany's industry to decarbonise are still to be taken the lack of discursive struggles has come to my surprise. In the discussion I reflect on how the positive sentiment, the discursive homogeneity and the great number of dominant storylines may come about.

Description: The original objectives for introducing Energy Performance Certificates (EPCs) were 1) to make energy performance transparent in the building market, as a measure of energy costs of using a building that a potential buyer or tenant would be interested in; and 2) to encourage energy efficiency renovation. However, the current implementation of EPC schemes in the Member States still shows significant challenges in achieving these two objectives. The recast of the EU Directive on the Overall Energy Performance of Buildings (EPBD) provides a chance to enhance both the usefulness and quality of EPCs and the EPC schemes overall. This document aims to inform both the debate on the recast of the EPBD and the enhancement of national EPC schemes in EU Member States. It presents the draft policy recommendations of the Horizon 2020 QualDeEPC project for making the EPBD and the national schemes more effective, particularly for deep renovation, and enhance their quality overall. The policy recommendations particularly target the link between EPCs and deep (energy) renovation1, while increasing the levels of ambition and convergence across the EU in terms of building renovation. Deep (energy) renovation is crucial for mitigating climate change and for energy security. The EPBD and all of its articles, as well as national EPC schemes, should aim to make deep (energy) renovation the default. This objective would be embedded and ensured in EPC schemes, if the policy recommendations provided in this document were adopted and implemented.

Description: At the next United Nations (UN) climate conference in the United Arab Emirates at the end of 2023, the first Global Stocktake (GST) of the Paris Agreement is due to conclude. The main goal of this process is to feed into a new round of Nationally Determined Contributions (NDCs) by Parties to the Agreement for 2035. In addition, the GST is aimed at identifying opportunities for strengthening international cooperation to achieve the Paris goals. The GST represents the first opportunity for Parties and other stakeholders to collectively highlight opportunities for international climate cooperation. Specifically, outcomes should plant the seeds for the development of concrete sectoral decarbonization roadmaps that could guide international cooperation in years to come.

Description: This Wuppertal Paper analyses the energy transition models of Colombia and Germany. The emphasis of the exercise is on an analysis of options for the complete decarbonization of the energy system in Colombia as a Global South country. To this end, it analyses the current situation, projections, public policy and narratives, and contrasts it with Germany as one of the countries of the Global North with which Colombia has historically maintained energy trade relations and is currently collaborating in the exploration of energy alternatives for decarbonization. Detailed analysis of sectoral energy consumption in Colombia shows the sectors with the highest fossil energy consumption (in this order): transport (fuels), industry (gas, coal), electricity generation (gas, coal) and residential (gas). We show the projected increase in demand for fuels and electricity, and calculate the amount of electricity theoretically needed to substitute fossil sources in each sector. We estimate the total electricity required for decarbonization via sector coupling and derive a first estimation of the range of additional renewable energy capacities needed to supply this demand. We find that required capacities are expectedly large (56-110 GW), depending on decarbonization pathways, and that export capacity beyond national demand may be limited. Our analysis of the policy and scenario arena in both countries finds that Colombia is still lacking both sector-specific decarbonization strategies and an embedding in a systemic vision of a systemic energy transition. Germany has more advanced sector strategies and (national) systemic visions, but lacks embedding assumptions on energy imports in a global-system analysis, i.e. in the analysis of an energy transition in potential exporting countries like Colombia. We formulate requirements to close these gaps in our conclusions.

Description: Rising energy costs have led to increased discussion about the social impact of the energy transition in Germany in recent years. In 2021, a gradually increasing CO2 tax was introduced. This paper analyzes the question of whether a CO2 tax can be socially just. Using data analysis and desk research, correlations between income and energy consumption in Germany are shown. In a short analysis, it is investigated which additional burdens different types of private households have to expect in the coming years due to the introduction of CO2 pricing on energy. In particular, the introduction of a per capita flat rate fed by CO2 tax revenues could be a suitable way to reduce the burden on low-income households.

Description: Studies show that people can tolerate elevated temperatures in the presence of appreciable air movement (e.g., from using ceiling fans). This minimises the use of air-conditioners and extends their set-point temperature (Tset), resulting in energy savings in space cooling. However, there is little empirical evidence on the energy savings from using ceiling fans with Room Air-Conditioners (RACs). To address this gap, we analysed the energy performance of RACs with both fixed-speed compressors and inverter technology at different set-point temperatures and ceiling fan speed settings in 15 residential Mixed-Mode Buildings (MMBs) in India. Thermal comfort conditions (as predicted by the Indian Model for Adaptive Comfort-Residential (IMAC-R)) with minimum energy consumption were maintained at a set-point temperature (𝑇set) of 28 and 30 C and a fan speed setting of one. Compared with a Tset of 24 °C, a 𝑇set of 28 and 30 °C resulted in energy savings of 44 and 67%, respectively. With the use of RACs, a configuration with a minimum fan speed was satisfactory for an optimal use of energy and for maintaining the conditions of thermal comfort. In addition, RACs with inverter technology used 34-68% less energy than fixed-speed compressors. With the rising use of RACs, particularly in tropical regions, the study's outcomes offer a significant potential for reducing space-cooling energy consumption and the resultant greenhouse gas (GHG) emissions.

Description: To combat climate change, it is anticipated that in the coming years countries around the world will adopt more stringent policies to reduce greenhouse gas emissions and increase the use of clean energy sources. These policies will also affect the industry sector, which means that industrial production is likely to progressively shift from CO2-emitting fossil fuel sources to renewable energy sources. As a result, a region's renewable energy resources could become an increasingly important factor in determining where energy-intensive industries locate their production. We refer to this pull factor as the "renewables pull" effect. Renewables pull could lead to the relocation of some industrial production as a consequence of regional differences in the marginal cost of renewable energy sources. In this paper, we introduce the concept of renewables pull and explain why its importance is likely to increase in the future. Using the examples of direct reduced iron (DRI) and ammonia production, we find that the future costs of climate-neutral production of certain products is likely to vary considerably between regions with different renewable energy resources. However, we also identify the fact that many other factors in addition to energy costs determine the decisions that companies make in term of location, leaving room for further research to better understand the future relevance of renewables pull.

Description: Analyzing previous international and national policy processes, the study offers recommendations for leveraging the Global Stocktake's (GST) outcomes for national climate action, especially for Nationally Determined Contributions (NDCs). It emphasizes the need for coordinated efforts to ensure the results of the GST influence national political discourse. It proposes communication strategies tailored to the different stages of the NDC policy process and diverse target audiences. The paper advocates for a nuanced and strategic approach to communication and emphasizes the importance of legitimacy and complexity in engaging stakeholders at different levels of decision-making.

Description: In recent years, the public discourse on the phase-out of carbon-intensive technologies and practices has come to a near consensus that a "just transition" is required. Yet, this term seems to have as many meanings as there are stakeholders using it. The purpose of this paper is to unpack the different meanings that regional stakeholders assign to it and the underlying dimensions of in(justice) that they invoke in their political communication. To this end, we employ a policy narrative analysis to study and compare the political discourse in four European coal and carbon-intensive mining regions: Ida-Virumaa (Estonia, oil shale), the Rhenish mining region (Germany, lignite), Upper Silesia (Poland, hard coal) and Western Macedonia (Greece, lignite). Specifically, we address the following research questions: Which narratives are characterising the political discourse around just transition? Which (in)justices are being invoked? Which patterns, similarities or differences are recognizable between regions? We found that hopeful narratives describing structural change as an opportunity to reinvent the region are prevalent in all regions. Strong narratives of resistance only prevail in Upper Silesia and Ida-Virumaa where a phase-out decision has not yet been adopted. In terms of injustices, we find surprisingly little evidence that injustices related to the immediate effects of the transformation (e.g. lay-offs and compensation for workers and companies) play an important role. Instead, the aspects related to the historical injustices produced by the legacy industrial system prevail. And perhaps most importantly, questions about access and allocation of the opportunities of the imminent transition are key and should be addressed more explicitly.

Description: The QualDeEPC project is aiming to both improve quality and cross-EU convergence of Energy Performance Certificate schemes, and the link between EPCs and deep renovation: High-quality Energy Performance Assessment and Certification in Europe Accelerating Deep Energy Renovation. The objective of the project is to improve the practical implementation of the assessment, issuance, design, and use of EPCs as well as their renovation recommendations, in the participating countries and beyond. This report serves as a compilation of the project's proposal for an enhanced and converging EPC assessment and certification scheme. It aims to provide a detailed description on the set of practical concepts, policy proposals, and tools for an enhanced EPC scheme towards deep renovation, developed by the QualDeEPC project. The project's substantial proposals both on EU and national level are presented in a comprehensive and rational way, guiding the relevant stakeholders, in particular the policy makers and competed bodies, on which steps need to be followed so as the proposals to be adapted and how the specific values can be determined in MSs. Furthermore, this report includes the project's proposal for defining "Deep Energy Renovation" based on a modified nZEB-based approach. The project's priorities A) to G) addressed are presented in the following order in this document, reflecting the importance of the enhanced EPC template form and the training of EPC assessors in such schemes: A) Improving the recommendations for renovation, which are provided on the EPCs, towards deep energy renovation; E) High user-friendliness of the EPC, by way of an enhanced EPC template form, including an introduction of the proposed "Energy Rating" indicator; D) Regular mandatory EPC assessor training or examination on assessment and renovation recommendations, required for certification/accreditation and registry; B) Online tool for comparing EPC recommendations to deep energy renovation recommendations; C) Creating Deep Renovation Network Platforms (DRNPs); F) & G) Voluntary/mandatory advertising guidelines for EPCs and Improving compliance with the mandatory use of EPCs in real estate advertisement.

Description: There is a growing body of scientific evidence supporting sufficiency as an inevitable strategy for mitigating climate change. Despite this, sufficiency plays a minor role in existing climate and energy policies. Following previous work on the National Energy and Climate Plans of EU countries, we conduct a similar content analysis of the recommendations made by citizen assemblies on climate change mitigation in ten European countries and the EU, and compare the results of these studies. Citizen assemblies are representative mini-publics and enjoy a high level of legitimacy. We identify a total of 860 mitigation policy recommendations in the citizen assemblies' documents, of which 332 (39 %) include sufficiency. Most of the sufficiency policies relate to the mobility sector, the least relate to the buildings sector. Regulatory instruments are the most often proposed means for achieving sufficiency, followed by fiscal and economic instruments. The average approval rate of sufficiency policies is high (93 %), with the highest rates for regulatory policies. Compared to National Energy and Climate Plans, the citizen assembly recommendations include a significantly higher share of sufficiency policies (factor three to six) with a stronger focus on regulatory policies. Consequently, the recommendations can be interpreted as a call for a sufficiency turn and a regulatory turn in climate mitigation politics. These results suggest that the observed lack of sufficiency in climate policy making is not due to a lack of legitimacy, but rather reflects a reluctance to implement sufficiency policies, the constitution of the policy making process and competing interests.

Description: Buildings constitute one of the main GHG emitting sectors, and energy efficiency is a key lever to reduce emissions in the sector. Global climate policy has so far mostly focused on economy-wide emissions. However, emission reduction actions are ultimately sectoral, and opportunities and barriers to achieving emission reductions vary strongly among sectors. This article therefore seeks to analyse to what extent more targeted global governance may help to leverage mitigation enablers and overcome barriers to energy efficiency in buildings. To this end, the article first synthesises existing literature on mitigation enablers and barriers as well as existing literature on how global governance may help address these barriers ("governance potential"). On this basis, the article analyses to what extent this governance potential has already been activated by existing activities of international institutions. Finally, the article discusses how identified governance gaps could be closed. The analysis finds that despite the local characteristics of the sector, global governance has a number of levers at its disposal that could be used to promote emission reductions via energy efficiency. In practice, however, lacking attention to energy efficiency in buildings at national level is mirrored at the international level. Recently, though, a number of coalitions demanding stronger action have emerged. Such frontrunners could work through like-minded coalitions and at the same time try to improve conditions for cooperation in the climate regime and other existing institutions.

Description: Considering that 40% of the European Union's energy consumption can be traced back to its buildings, it is essential to improve their energy efficiency in order to achieve the EU's energy efficiency targets. Both the rate of energy renovation and its depth, i.e. the amount of energy savings during a renovation, need to be improved. Energy Performance Certificates (EPC), regulated by the EU's Energy Performance of Buildings Directive (EPBD), are an important instrument to enhance the market uptake of energy-efficient new buildings and the energy-efficient renovation of existing buildings. Against this background, the Horizon2020 funded project QualDeEPC will work on EU-wide convergence of the building assessment and the issuance, design, and use of quality-enhanced EPCs as well as their recommendations for building renovation. The aim is to make these recommendations coherent with deep energy renovation towards a nearly-zero energy building stock by 2050. The first part of the QualDeEPC project (work package 2) aims to identify the priorities for elements of EPC schemes that show a need to be improved, and for which the project will investigate further and propose how the elements can be improved. The first step in identifying these priorities is taking stock of the existing EPC schemes. Based on the input from all national consortium partners and other sources, the Wuppertal Institute prepared this detailed overview of the country-specific EPC assessment and certification procedures and their links to other policies and programmes, existing initiatives, and projects. The analysis was based on a list of almost 50 potential options for enhancing the existing EPC schemes. The aim of this deliverable is to present this stock-taking by a detailed analysis on which of the potential enhanced EPC elements are already implemented in which form in which country, covering all 28 countries that were EU member states until 31 January 2020. All partners conducted bilateral interviews with the major actors in the EPC procedures, including executive bodies on EPC at regional and/or national level. For countries not represented in the Consortium, Wuppertal Institut and EAP conducted specific literature research, e.g. from the Concerted Action EPBD, and aimed to obtain contributions from other member states. The information collected allows a detailed presentation on the elements implemented as well as a cross-country comparison matrix (see Annex I) in this report, which outlines the current EPC practices across the EU regarding the elements of a good practice scheme or innovative improvement options, their comparability, compliance with EU legislation, and to which extent they differ or converge. The results show, once more, the high diversity in EPC schemes across the EU. They also provide useful information in at least two directions: 1) which improvement options are not yet implemented at all or in sufficient quality in most QualDeEPC partner countries as well as other EU member states, and could therefore be interesting candidates for the further work of the QualDeEPC project in development, testing, discussion, and possibly implementation of elements for enhanced and converging EPC schemes; and 2) which countries, within or beyond the QualDeEPC project, offer good practice examples for the implementation of these options that could serve to guide the development and implementation in other countries. This deliverable will thus serve as a basis for the upcoming tasks to develop priorities and actual proposals for improvement of EPC schemes.

Description: The 2015 Paris Agreement relies on Nationally Determined Contributions (NDCs) to outline each country's policies and plans for reducing greenhouse gas (GHG) emissions. To strengthen global climate action and achieve the Agreement's temperature goal, it is crucial to enhance the ambition level of NDCs every 5 years. While previous studies have explored the ambition of initial NDCs, limited research has delved into the factors driving the enhancement or lack thereof in NDCs' emission reduction plans. This study employs a mixed-method design to investigate the determinants of NDC enhancement. First, we analyse the updated or revised NDCs of 111 countries using quantitative methods. Second, we conduct qualitative case studies focusing on Brazil and South Africa. Our findings reveal that countries that engaged in stakeholder consultations with civil society, business, and labour groups prior to developing their updated or revised NDCs were more likely to enhance their greenhouse gas reduction targets. These results are further supported by the case studies. South Africa conducted comprehensive consultations and submitted an enhanced GHG target, while Brazil, which did not arrange open consultations, did not improve its target. This study underscores the significance of comprehensive and transparent stakeholder engagement processes, highlighting their potential to drive enhanced NDCs. By involving diverse stakeholders, including civil society, business, and labour groups, countries can foster greater ambition and effectiveness in their climate action, ultimately contributing to the global effort to combat climate change.

Description: The international architecture competition Solar Decathlon Europe was held in Wuppertal in 2022 and focused on sustainable building and living in the city. The student teams participating in the competition developed buildings that would enable climate-friendly living and be tailored to the "Mirke" district in Wuppertal and the individual needs of the residents in this neighborhood. Not only the neighborhood was the focus of the competition, but also the residents of the Mirke district were involved in the project through a neighborhood panel. As part of the Mirke neighborhood panel, three survey waves were conducted between May 2021 and August 2022. The results and insights gained from the neighborhood panel were incorporated into the project and shared with the architectural teams participating in the competition. In addition, the results were shared and discussed with the urban development department of the city of Wuppertal, local initiatives, and other partners in the neighborhood.

Description: Biodiversity is under threat all over the planet. Implementing sustainable out-of-home catering (OHC) is a key way to reduce the environmental impact of the agri-food sector. Thus far, there have been no studies that show the impact of food on biodiversity at the menu level in Germany. This means that neither commercial kitchens nor their patrons can record the biodiversity impact of the menus or dishes served there. This article describes the development of an assessment framework and some initial findings. The framework was developed on the basis of a systematic literature review and expert interviews. Taking this as a starting point, an indicator-based approach was developed with a focus on land use. The approach was then validated by assessing recipes used at OHC facilities. The results show that using the BiTe Biodiversity Index (BBI) that was developed, it is possible to assess the biodiversity impacts of meals and optimize them at the level of the dish. The article outlines the possible areas for improvement. Overall, it is clear that this approach can already be used in the OHC context today.

Description: Power-law city-size distributions are a statistical regularity researched in many countries and urban systems. In this history of science treatise we reconsider Felix Auerbach’s paper published in 1913. We reviewed his analysis and found (i) that a constant absolute concentration, as introduced by him, is equivalent to a power-law distribution with exponent ≈1, (ii) that Auerbach describes this equivalence, and (iii) that Auerbach also pioneered the empirical analysis of city-size distributions across countries, regions, and time periods. We further investigate his legacy as reflected in citations and find that important follow-up work, e.g. by Lotka (Elements of physical biology. Williams & Wilkins Company, Baltimore, 1925) and Zipf (Human behavior and the principle of least effort: an introduction to human ecology, Martino Publishing, Manfield Centre, CT (2012), 1949), does give proper reference to his discovery - but others do not. For example, only approximately 20% of city-related works citing Zipf (1949) also cite Auerbach (Petermanns Geogr Mitteilungen 59(74):74–76, 1913). To our best knowledge, Lotka (1925) was the first to describe the power-law rank-size rule as it is analyzed today. Saibante (Metron Rivista Internazionale di Statistica 7(2):53–99, 1928), building on Auerbach and Lotka, investigated the power-law rank-size rule across countries, regions, and time periods. Zipf's achievement was to embed these findings in his monumental 1949 book. We suggest that the use of “Auerbach–Lotka–Zipf law” (or "ALZ-law") is more appropriate than "Zipf's law for cities", which also avoids confusion with Zipf’s law for word frequency. We end the treatise with biographical notes on Auerbach.

Description: Established in 2016, the German-Japanese Energy Transition Council (GJETC) strives to promote bilateral cooperation between Germany and Japan on energy transition. Among other studies and topical papers, an output paper in 2020 (Rauschen et al., 2020) already compared the energy efficiency in buildings in both countries with a particular focus on heating and cooling. One important finding of this output paper was that further efforts in the building sector are needed to improve the energy efficiency of buildings in Germany and Japan. Following the more ambitious climate protection targets in both countries, this study seeks to analyze the German and Japanese policies put in place to accelerate the decarbonization of the building sector. The decarbonization of the vast number of buildings that both Japan and Germany are facing will be a major contribution to achieving the GHG reduction targets of both countries and should continue to be discussed among experts and developed into a discussion among policy makers. This report examines and compares the characteristics of the building stock in both countries, as well as existing policies and new strategies and policies that are planned or discussed to achieve energy conservation and decarbonization of buildings. The current shape of buildings, especially houses, is greatly influenced by the land area of the country corresponding to the available space for buildings, the natural environment surrounding the country, the natural resources available, and the lifestyle and cultural ideas that have been passed down and taken root over time. Therefore, it might be difficult to compare them and the corresponding strategies and policies with the same yardstick, so we also discuss common or deviant situations. Through this joint research, we aim to find each other's advantages and challenges and to develop useful and concrete policy recommendations that will contribute to decarbonization policies in both countries.

Description: Better integration of climate action and sustainable development can help enhance the ambition of the next nationally determined contributions, as well as implementation of the Sustainable Development Goals. Governments should use this year as an opportunity to emphasize the links between climate and sustainable development.

Description: The twenty-seventh Conference of the Parties (COP27) to the United Nations Framework Convention on Climate Change (UNFCCC) in Sharm el-Sheikh made history by for the first time ever discussing and ultimately even agreeing to establish a fund to address loss and damage caused by climate change. However, the conference did little to limit the occurrence of loss and damage in the first place by containing the extent of climate change. This article discusses the conference's outcomes in the areas of mitigation and adaptation, loss and damage, the Global Stocktake, cooperation under Article 6 of the Paris Agreement, climate finance, and gender-responsiveness. While modest progress can be observed, it is too slow to actually achieve the objectives of the Paris Agreement. This pace is leading many, not least the most vulnerable countries, to search for parallel arenas of cooperation.

Description: While digital technologies hold significant transformational potential, anecdotal evidence suggests that the digital transformation might not be directed towards sustainable development sufficiently. Drawing on a modified and extended version of the framework proposed by Wanzenböck et al. (2020), we explore the cases of the circular economy and the transition towards a sustainable energy system in the twin transition. Making use of insights from 20 expert interviews and two in-depth interviews, we aim to gain a first careful indication of the convergence/divergence in societal views on key problems and solutions across different dimensions (technological, economic, socio-cultural, regulatory) and derive insights for integrated policy-making. Thereby the study contributes to bridging the existing gap between mission-oriented policies and the twin transition. Overall, our first insights indicate that while showing high similarities in the structure of problems and solutions across cases, the variety in wickedness (contestation, complexity, uncertainty) calls for differentiated policy-making: Significant parts of the relatively young twin transition might be in a state of disorientation where societal views on problems and solutions diverge. This would require policy-makers to follow a "discovery-mode" (basic research, experiments and monitoring) with only selected diffusion-focused strategies. Further, we show that missions in the twin transition require highly flexible policy-making as different approaches need to be applied simultaneously. Finally, there are several options for exploiting synergies in policy-making due to some overlapping characteristics as well as learning opportunities between cases. We believe that particularly our holistic perspective on the twin transition can yield substantial guidance for researchers and policy-makers in the field.

Description: Agriculture is a major sector responsible for greenhouse gas emissions. Local food production can contribute to reducing transport-related emissions. Since most of the worldwide population lives in cities, locally producing food implies practicing agriculture in urban and peri-urban areas. Exemplary, we analyze the potential to produce fresh vegetables within Berlin, Germany. We investigate the spatial extent of five different urban spaces for soil-based agriculture or gardening, i.e., non-built residential areas, allotment gardens, rooftops, supermarket parking lots, and cemeteries. We also quantify inputs required for such food production in terms of water, human resources, and investment. Our findings highlight that up to 82% of Berlin’s vegetable demand could be produced within the city, based on a reasonable validation of existing areas. Meeting this potential requires 42 km2 of urban spaces for cultivation, a considerable amount of irrigation water, around 17 thousand gardeners, and over 750 million EUR of initial investments. The final vegetable cost would be around 2 EUR to 10 EUR per kg without any profit margin. We conclude that it is realistic to produce a significant amount of Berlin's vegetable demand within the city, even if it comes with great challenges.

Description: The accurate knowledge of the Earth’s orientation and rotation in space is essential for a broad variety of scientific and societal applications. Among others, these include global positioning, near-Earth and deep-space navigation, the realisation of precise reference and time systems as well as studies of geodynamics and global change phenomena. In this paper, we present a refined strategy for processing and combining Very Long Baseline Interferometry (VLBI), Satellite Laser Ranging (SLR), Global Navigation Satellite Systems (GNSS), and Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) observations at the normal equation level and formulate recommendations for a consistent processing of the space-geodetic input data. Based on the developed strategy, we determine final and rapid Earth rotation parameter (ERP) solutions with low latency that also serve as the basis for a subsequent prediction of ERPs involving effective angular momentum data. Realising final ERPs on an accuracy level comparable to the final ERP benchmark solutions IERS 14C04 and JPL COMB2018, our strategy allows to enhance the consistency between final, rapid and predicted ERPs in terms of RMS differences by up to 50% compared to existing solutions. The findings of the study thus support the ambitious goals of the Global Geodetic Observing System (GGOS) in providing highly accurate and consistent time series of geodetic parameters for science and applications.

Description: BACKGROUND AND OBJECTIVES: Soil or rock types in a region are often interpreted qualitatively by visually comparing various geophysical properties such as seismic wave velocity and vulnerability, as well as gravity data. Better insight and less human-dependent interpretation of soil types can be obtained from a joint analysis of separated and independent geophysical parameters. This paper discusses the application of a neural network approach to derive rock properties and seismic vulnerability from horizontal-to-vertical seismic ratio and seismic wave velocity data recorded in Majalengka-West Java, Indonesia.METHODS: Seismic microtremors were recorded at 54 locations and additionally multichannel analyses of surface wave experiments were performed at 18 locations because the multichannel analyses of surface wave experiment needs more effort and space. From the two methods, the values of the average shear wave velocity for the upper 30 meters, peak amplitudes and the dominant frequency between the measurement points were obtained from the interpolation of those geophysical data. Neural network was then applied to adaptively cluster and map the geophysical parameters. Four learning model clusters were developed from the three input seismic parameters: shear wave velocity, peak amplitude, and dominant frequency. FINDINGS: Generally, the values of the horizontal to vertical spectral ratios in the west of the study area were low (less than 5) compared with those in the southeastern part. The dominant frequency values in the west were mostly low at around 0.1–3 Hertz, associated with thick sedimentary layer. The pattern of the shear wave velocity map correlates with that of the horizontal to vertical spectral ratio map as the amplification is related to the soil or rock rigidity represented by the shear wave velocity. The combination of the geophysical data showed new features which is not found on the geological map such as in the eastern part of the study area. CONCLUSION: The application of the neural network based clustering analysis to the geophysical data revealed four rock types which are difficult to observe visually. The four clusters classified based on the variation of the geophysical parameters show a good correlation to rock types obtained from previous geological surveys. The clustering classified safe and vulnerable regions although detailed investigation is still required for confirmation before further development. This study demonstrates that low-cost geophysical experiments combined with neural network-based clustering can provide additional information which is important for seismic hazard mitigation in densely populated areas.

Description: Tropical Lake Sentani in the Indonesian Province Papua consists of four separate basins and is surrounded by a catchment with a very diverse geology. We characterized the surface sediment (upper 5 cm) of the lake’s four sub-basins based on multivariate statistical analyses (principal component analysis, hierarchical clustering) of major element compositions obtained by X-ray fluorescence scanning. Three types of sediment are identified based on distinct compositional differences between rivers, shallow/proximal and deep/distal lake sediments. The different sediment types are mainly characterized by the correlation of elements associated with redox processes (S, Mn, Fe), carbonates (Ca), and detrital input (Ti, Al, Si, K) derived by river discharge. The relatively coarse-grained river sediments mainly derive form the mafic catchment geology and contribution of the limestone catchment geology is only limited. Correlation of redox sensitive and detrital elements are used to reveal oxidation conditions, and indicate oxic conditions in river samples and reducing conditions for lake sediments. Organic carbon (TOC) generally correlates with redox sensitive elements, although a correlation between TOC and individual elements change strongly between the three sediment types. Pyrite is the quantitatively dominant reduced sulfur mineral, monosulfides only reach appreciable concentrations in samples from rivers draining mafic and ultramafic catchments. Our study shows large spatial heterogeneity within the lake’s sub-basins that is mainly caused by catchment geology and topography, river runoff as well as the bathymetry and the depth of the oxycline. We show that knowledge about lateral heterogeneity is crucial for understanding the geochemical and sedimentological variations recorded by these sediments. The highly variable conditions make Lake Sentani a natural laboratory, with its different sub-basins representing different depositional environments under identical tropical climate conditions.

Description: Along the Northern Chilean active continental margin, the subducting Nazca plate is characterized by a rough sea floor topography that has been suggested to control the rupture behaviour of megathrust earthquakes. However, there is still debate of what structures exactly controlled the extent of the rupture of the Mw 8.12014 April 1st Iquique earthquake and why it only broke 1/3 of a large seismic gap that last ruptured completely in 1877. To better understand the seismotectonic segmentation of the northern Chilean convergent margin, we use datasets from different geophysical and geodetic studies in this area to produce a 3D model. We combine depth migrated images of the two northernmost multi-channel seismic reflection CINCA’95 (Crustal Investigations off- and onshore Nazca Plate/Central Andes) lines, bathymetry data, coseismic slip models, geodetic coupling, seismic b values, relocated seismic events and the morphology of the subduction interface from gravity modelling. The interface morphology shows a prominent surface relief that spacially correlates with the rupture process of the mainshock on April 1st and also for the largest aftershock on April 3rd. The main slip area exhibits a strong correlation with a large elongated topographic depression of the subducting slab. An elongated topographic high on the subducting plate to the south of that depression correlates with low pre-seismic locking and very likely acted as a barrier for rupture propagation for the main shock, as well as for the largest after shock. A subducted circular topographic high of 25 km in diameter located updip of the rupture area, possibly prevented coseismic slip to rupture all the way up to the trench axis. Thus, our observations support that subducting sea floor morphology plays an important role controlling rupture processes.

Description: Modern continental crust has evolved to a more potassic, granitic composition than early continental crust, which comprises largely sodic TTG-suite magmas. The present paradigm holds that the latter are largely “juvenile” (in the sense that the time from mantle extraction to felsic crust production is comparatively short, of the order 10–100 Ma) while the former represent recycled older crust of igneous or sedimentary composition. The data from high-Mg diorites, tonalites, granodiorites and potassic granites of the 125–115 Ma Menglian Batholith (SE Tibet) exemplify the modern situation and can therefore be used to constrain current crust formation processes. These rocks have higher concentrations of incompatible elements than magmatic rocks from typical continental arc settings, with a continuum of increasing K2O/Na2O ratios, SiO2, K2O, Rb, and Th concentrations juxtaposed with decreasing MgO, CaO, and Sr. They consistently record both higher zircon δ18O values than mantle values and decoupled Ndsingle bondHf isotope systems caused by the interaction of subducted sediments with the mantle wedge. Petrogenetic mechanisms that connect the suite include crystal fractionation within the diorites, melting of the lower crust induced by advection of heat and water by the diorites, and high-level fractionation of the tonalite-granodiorite suite to produce the high-silica granites. Therefore, this example of modern fertile continental crust had a five-stage evolution: (1) subduction-enrichment of the mantle source, (2) mantle melting to produce mafic magmas that pooled in or below the lower crust, (3) mafic magma differentiation to produce the tonalite-granodioritic magmas controlled by crystal-liquid equilibria, (4) crustal melting and admixture to the evolving felsic magmas and (5) final high-level fractionation and melt extraction to produce the silicic extreme, enriched in incompatible elements such as Rb, Th and K. This model could be a general mechanism for how modern mature continental crust evolves. Importantly, it indicates a significant role for mafic magmas and thence a more important role for juvenile additions than is generally accepted.

Description: Most tectonic models consider that the “Samail subduction zone” was the only subduction zone at the mid-Cretaceous convergent Arabian margin. We report four new Rb-Sr multimineral isochron ages from high-pressure (HP) rocks and a major shear zone of the uppermost Ruwi-Yiti Unit of the Saih Hatat window in the Oman Mountains of NE Arabia. These ages demand a reassessment of the intraoceanic suprasubduction-zone evolution that formed the Samail Ophiolite and its metamorphic sole in the Samail subduction zone. Our new ages constrain waning HP metamorphism of the Ruwi subunit at ∼99-96 Ma and associated deformation in the Yenkit shear zone between ∼104 and 93 Ma. Our ages for late stages of deformation and HP metamorphism (thermal gradients of ∼8–10°C km−1) overlap with published ages of ∼105-102 Ma for Samail-subduction-zone prograde-to-peak metamorphism (thermal gradients of ∼20–25°C km−1), subsequent decompressional partial melting of the metamorphic sole and suprasubduction-zone crystallization of the Samail Ophiolite (thermal gradients of ∼30°C km−1) between ∼100 and 93 Ma. Thermal considerations demand that two subduction zones existed at the mid-Cretaceous Arabian margin. High-pressure metamorphism of the Ruwi-Yiti rocks occurred in a mature, thermally equilibrated “Ruwi subduction zone” that formed at ∼110 Ma. Initiation of the infant, thermally unequilibrated and, thus, immature, outboard intraoceanic Samail subduction zone occurred at ∼105 Ma. The Samail Ophiolite and its metamorphic sole were then thrust over the exhuming Ruwi-Yiti HP rocks and onto the Arabian margin after ∼92 Ma, while the bulk of the Saih Hatat HP rocks below the Ruwi-Yiti Unit started to be underthrust in the Ruwi subduction zone.

Description: A massive landslide often causes long-lasting instability dynamics that need to be analyzed in detail for risk management and mitigation. Multiple satellite remote sensing observations, in-situ measurements, and geophysical approaches have been jointly implemented to monitor and interpret the life cycle of landslides and their failure mechanisms from various perspectives. In this work, we propose a framework where satellite optical and synthetic aperture radar (SAR) remote sensing techniques are combined with feature extractions using independent component analysis (ICA) and a mathematical relaxation model to assess the complete four-dimensional (4D) spatiotemporal patterns of post-failure slope evolution. The large, deep-seated Aniangzhai landslide in Southwest China that occurred on 17 June 2020 is comprehensively analyzed and characterized for its post-failure mechanism. Time series of Planet high-resolution optical images are first explored to derive the large horizontal motions for the first six months after the failure. Spatiotemporal dynamics of line-of-sight (LOS) displacement in the landslide body are then derived between November 2020 and February 2022 by combining 40 TerraSAR-X (TSX) High-resolution Spotlight (HS) images and 76 medium-resolution Sentinel-1 (S1) SAR datasets using Multi-temporal InSAR (MTI) method. The InSAR-derived results are subsequently analyzed with ICA to find common deformation components of points between optical and MTI results, indicating the same temporal evolution in the deformation pattern. Finally, the complete 4D deformation field for the whole post-failure period is modeled using a decaying exponential model representing stress relaxation after the failure by integrating multiple remote sensing datasets. Cross-correlation analysis of Planet imagery shows a decaying exponential pattern of post-failure displacements with an approximately 94% reduction in the deformation rate after six months with respect to the co-failure event. MTI analysis suggests a maximum LOS displacement rate of approximately 30 cm/year over the main failure body from November 2020 to February 2022; while the high-resolution TSX datasets show irreplaceable advantages in choosing the number of measurement points in MTI analysis with the number of measurement points being five times larger than those obtained by S1 datasets. The ICA analysis reveals three main types of kinematic patterns in the temporal evolution of post-failure deformation in MTI results, the dominant one being an exponential declining pattern similar to the results from Planet observations. Integrated 4D deformation modeling suggests that the most significant post-failure displacement mainly occurred toward the west, amounting to 28 m during the entire post-failure acquisitions from June 2020 until February 2022. Additionally, maximum displacements of 17 m and 19 m occurred in this period toward the north and downward, respectively.

Description: Planned decommissioning of coal-fired plants in Europe requires innovative technical and economic strategies to support coal regions on their path towards a climate-resilient future. The repurposing of open pit mines into hybrid pumped hydro power storage (HPHS) of excess energy from the electric grid, and renewable sources will contribute to the EU Green Deal, increase the economic value, stabilize the regional job market and contribute to the EU energy supply security. This study aims to present a preliminary phase of a geospatial workflow used to evaluate land suitability by implementing a multi-criteria decision making (MCDM) technique with an advanced geographic information system (GIS) in the context of an interdisciplinary feasibility study on HPHS in the Kardia lignite open pit mine (Western Macedonia, Greece). The introduced geospatial analysis is based on the utilization of the constraints and ranking criteria within the boundaries of the abandoned mine regarding specific topographic and proximity criteria. The applied criteria were selected from the literature, while for their weights, the experts’ judgement was introduced by implementing the analytic hierarchy process (AHP), in the framework of the ATLANTIS research program. According to the results, seven regions were recognized as suitable, with a potential energy storage capacity from 1.09 to 5.16 GWh. Particularly, the present study’s results reveal that 9.27% (212,884 m2) of the area had a very low suitability, 15.83% (363,599 m2) had a low suitability, 23.99% (550,998 m2) had a moderate suitability, 24.99% (573,813 m2) had a high suitability, and 25.92% (595,125 m2) had a very high suitability for the construction of the upper reservoir. The proposed semi-automatic geospatial workflow introduces an innovative tool that can be applied to open pit mines globally to identify the optimum design for an HPHS system depending on the existing lower reservoir.

Description: The minor and trace element composition of minerals provides critical insights into a variety of geological processes. Multi-element mapping by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is an important technique applied for this purpose and although the method is rapidly advancing, there remains a fundamental compromise between spatial resolution, detection limit, and experiment duration when using sequential mass analyzers. To address the limitation of limited analyte selection for high spatial resolution maps imposed by the sequential nature of typical quadrupole (Q)-ICP-MS, we tested the Aerosol Rapid Introduction System (ARIS) for repeat mapping of the same area. The ARIS is a high-speed transfer tubing system that reduces aerosol washout times, permitting resolution of individual pulses at 40–60 Hz. Here, the ARIS was tested not for pulse resolution but with novel operating conditions optimized to perform fast, high spatial resolution mapping of minor and trace element distribution in pyrite and marcasite. For this purpose, ablation was conducted with a 5 µm beam aperture, a repetition rate of 50 Hz, and a continuous stage scan speed of 40 µm s−1. For each LA-Q-ICP-MS map, data were acquired for six elements with an acquisition time of 20 ms per element. This deliberately reduced the individual pulse resolution of the ARIS but instead exploited the spatial resolution and sensitivity gains afforded by the high-laser repetition rate combined with efficient aerosol transfer. The new method successfully mapped trace elements at single to double-digit parts per million levels, and the maps reveal fine-scale zoning of trace elements with an effective x and y resolution of 5 µm, while white light interferometry showed that for each experiment, only ca. 1 µm of the sample was removed. Repeated mapping of the same area showed excellent correspondence not only between element concentrations in successive experiments but also in the shape, dimension, and location of regions of interest defined by concentration criteria. The very good repeatability of the elemental maps indicates that for studies requiring more analytes, successive mapping of additional elements is possible. By contrast with conventional very small spot (i.e., 5 µm) analysis, fast repetition rate and stage scan speed mapping avoids down-hole fractionation effects and minimizes accidental analysis of buried invisible inclusions. Compared to conventional LA-ICP-MS mapping, the method reduces the experiment time by 4–8 times.

Description: This paper presents a series of surface experimental simulations of methane-oriented underground coal gasification using hydrogen as gasification medium. The main aim of the experiments conducted was to evaluate the feasibility of methane-rich gas production through the in situ coal hydrogasification process. Two multi-day trials were carried out using large scale gasification facilities designed for ex situ experimental simulations of the underground coal gasification (UCG) process. Two different coals were investigated: the “Six Feet” semi-anthracite (Wales) and the “Wesoła" hard coal (Poland). The coal samples were extracted directly from the respective coal seams in the form of large blocks. The gasification tests were conducted in the artificial coal seams (0.41 × 0.41 × 3.05 m) under two distinct pressure regimes - 20 and 40 bar. The series of experiments conducted demonstrated that the physicochemical properties of coal (coal rank) considerably affect the hydrogasification process. For both gasification pressures applied, gas from “Six Feet” semi-anthracite was characterized by a higher content of methane. The average CH4 concentration for “Six Feet” experiment during the H2 stage was 24.12% at 20 bar and 27.03% at 40 bar. During the hydrogasification of “Wesoła" coal, CH4 concentration was 19.28% and 21.71% at 20 and 40 bar, respectively. The process was characterized by high stability and reproducibility of conditions favorable for methane formation in the whole sequence of gasification cycles. Although the feasibility of methane-rich gas production by underground hydrogasification was initially demonstrated, further techno-economic studies are necessary to assess the economic feasibility of methane production using this process.

Description: Forest soils have large contents of carbon (C) and total nitrogen (TN), which have significant spatial variability laterally across landscapes and vertically with depth due to decomposition, erosion and leaching. Therefore, the ratio of C to TN contents (C:N), a crucial indicator of soil quality and health, is also different depending on soil horizon. These attributes can cost-effectively and rapidly be estimated using visible–near infrared–shortwave infrared (VNIR–SWIR) spectroscopy. Nevertheless, the effect of different soil layers, particularly over large scales of highly heterogeneous forest soils, on the performance of the technique has rarely been attempted. This study evaluated the potential of VNIR–SWIR spectroscopy in quantification and variability analysis of C:N in soils from different organic and mineral layers of forested sites of the Czech Republic. At each site, we collected samples from the litter (L), fragmented (F) and humus (H) organic layers, and from the A1 (depth of 2–10 cm) and A2 (depth of 10–40 cm) mineral layers providing a total of 2505 samples. Support vector machine regression (SVMR) was used to train the prediction models of the selected attributes at each individual soil layer and the merged layer (profile). We further produced the spatial distribution maps of C:N as the target attribute at each soil layer. Results showed that the prediction accuracy based on the profile spectral data was adequate for all attributes. Moreover, F was the most accurately predicted layer, regardless of the soil attribute. C:N models and maps in the organic layers performed well although in mineral layers, models were poor and maps were reliable only in areas with low and moderate C:N. On the other hand, the study indicated that reflectance spectra could efficiently predict and map organic layers of the forested sites. Although, in mineral layers, high values of C:N (≥ 50) were not detectable in the map created based on the reflectance spectra. In general, the study suggests that VNIR–SWIR spectroscopy has the feasibility of modelling and mapping C:N in soil organic horizons based on national spectral data in the forests of the Czech Republic

Description: We present a study to estimate the large-scale landscape history of a continental margin, by establishing a source-to-sink volume balance between the eroding onshore areas and the offshore basins. Assuming erosion as the primary process for sediment production, we strive to constrain a numerical model of landscape evolution that balances the volumes of eroded materials from the continent and that deposited in the corresponding basins, with a ratio imposed for loss of erosion products. We use this approach to investigate the landscape history of Madagascar since the Late Cretaceous. The uplift history prescribed in the model is inferred from elevations of planation surfaces formed at various ages. By fitting the volumes of terrigenous sediments in the Morondava Basin along the west coast and the current elevation of the island, the landscape evolution model is optimized by constraining the erosion law parameters and ratios of sediment loss. The results include a best-fit landscape evolution model, which features two major periods of uplift and erosion during the Late Cretaceous and the middle to late Cenozoic. The model supports suggestions from previous studies that most of the high topography of the island was constructed since the middle to late Miocene, and on the central plateau the erosion has not reached an equilibrium with the high uplift rates in the late Cenozoic. Our models also indicate that over the geological time scale, a significant portion of materials eroded from Madagascar was not archived in the offshore basin, possibly consumed by chemical weathering, the intensity of which might have varied with climate.

Description: The interpretation of low-temperature thermochronology (LTT) data in magmatic and metallogenic provinces requires a knowledge of the geothermal field through time. There, the challenge is differentiating rapid cooling following transient perturbations of the geotherms (reheating) from exhumational cooling induced by erosion during tectonic uplift or normal faulting. The Takab Range Complex (NW Iran) is a basement-cored range of the Arabia-Eurasia collision zone that experienced voluminous Eocene to Miocene magmatism and mineralization. Our new apatite and zircon (U-Th-Sm)/He and apatite fission track data, together with field observations, a dedicated numerical thermal model, and a re-evaluation of available geochronology data document the occurrence of a complex geological and thermal history including: (a) late Cretaceous-Paleocene exhumation possibly controlled by regional contractional deformation followed by Eocene deposition; (b) Oligocene to possibly early Miocene (29 to 22–20 Ma) exhumation of basement rocks from 13 to 8 km of depth, most likely through normal faulting during a thermal anomaly that led to migmatization and partial melting; (c) early to late Miocene (∼22–20 or earlier to 11–10 Ma) regional subsidence with deposition of an up to ∼2- to 3-km-thick Oligo-Miocene sedimentary sequence in association with the emplacement of shallow intrusions, which led to a partial to total reset of our LTT systems sometime between 18 and 13 Ma; and (e) erosional exhumation after 11–10 Ma with the development of a transpressional system and a master, right-lateral, strike slip fault (Chahartagh Fault). Our data highlights the impact of magmatic reheating on LTT ages in areas affected by intense magmatism.

Description: To share best practices and to foster the research data management (RDM) community within Helmholtz, the Helmholtz Open Science Office hosted its first "Helmholtz Open Science Practice Forum Research Data Management" virtually in February 2022. A follow-up event on October 20, 2022 has taken up and continued this theme. The following aspects were highlighted through presentations with ample time for discussion in the forum: - Thinking and linking data, text, and research software together - Data Stewards, Data Librarians, Research Data Managers, Data Curators... – Their profiles and roles in Helmholtz - Data Management Plans – DMPs as Living Documents - Monitoring data publications

Description: Improving and homogenizing time and space reference systems on Earth and, more specifically, realizing the Terrestrial Reference Frame (TRF) with an accuracy of 1 mm and a long-term stability of 0.1 mm/year are relevant for many scientific and societal endeavors. The knowledge of the TRF is fundamental for Earth and navigation sciences. For instance, quantifying sea level change strongly depends on an accurate determination of the geocenter motion but also of the positions of continental and island reference stations, such as those located at tide gauges, as well as the ground stations of tracking networks. Also, numerous applications in geophysics require absolute millimeter precision from the reference frame, as for example monitoring tectonic motion or crustal deformation, contributing to a better understanding of natural hazards. The TRF accuracy to be achieved represents the consensus of various authorities, including the International Association of Geodesy (IAG), which has enunciated geodesy requirements for Earth sciences. Moreover, the United Nations Resolution 69/266 states that the full societal benefits in developing satellite missions for positioning and Remote Sensing of the Earth are realized only if they are referenced to a common global geodetic reference frame at the national, regional and global levels. Today we are still far from these ambitious accuracy and stability goals for the realization of the TRF. However, a combination and co-location of all four space geodetic techniques on one satellite platform can significantly contribute to achieving these goals. This is the purpose of the GENESIS mission, a component of the FutureNAV program of the European Space Agency. The GENESIS platform will be a dynamic space geodetic observatory carrying all the geodetic instruments referenced to one another through carefully calibrated space ties. The co-location of the techniques in space will solve the inconsistencies and biases between the different geodetic techniques in order to reach the TRF accuracy and stability goals endorsed by the various international authorities and the scientific community. The purpose of this paper is to review the state-of-the-art and explain the benefits of the GENESIS mission in Earth sciences, navigation sciences and metrology. This paper has been written and supported by a large community of scientists from many countries and working in several different fields of science, ranging from geophysics and geodesy to time and frequency metrology, navigation and positioning. As it is explained throughout this paper, there is a very high scientific consensus that the GENESIS mission would deliver exemplary science and societal benefits across a multidisciplinary range of Navigation and Earth sciences applications, constituting a global infrastructure that is internationally agreed to be strongly desirable.

Description: The study of Electro Magnetic Ion Cyclotron (EMIC) wave-induced electron precipitation has a legacy in early work suggesting EMIC waves could precipitate relativistic electrons. As such, EMIC waves represent a significant loss process for the Outer Radiation Belt, and deposit high energy electron precipitation flux deep into the atmosphere. Here we present an analysis of an example of EMIC-induced electron precipitation observed by two satellites in Low Earth Orbit, combined with EMIC wave signatures in ground-based magnetometers in Finland, and Antarctica. Electron precipitation spectral information is provided by satellite data which considers the energy range of scattered electrons during the potential EMIC wave event. We investigate the high energy resolution DEMETER IDP electron measurements in the 80 keV - 2 MeV range, when the detector was looking into the bounce-loss-cone, i.e., flying over the North Atlantic region. In order to assess the effect of potential proton precipitation contamination of the IDP detector we use nearby POES proton flux measurements, compensating for the IDP protective aluminium foil through a calculation of the attenuation of the proton spectrum using the integrated MULASSIS transport code. Our results are considered in the context of recent work indicating a wide energy range of non-relativistic electron precipitation is present in EMIC-induced precipitation in addition to the relativistic energy electrons suggested from the original theoretical suggestions. Our confirmation of non-relativistic energy ranges in EMIC-induced precipitation events supports the atmospheric chemical modelling analysis undertaken recently which showed that EMIC-induced precipitation is capable of causing notable composition changes.

Description: In Germany, climate resilient tree species are increasingly used in the process of forest conversion towards climate-change adapted stands. However, information on the impact of this conversion on groundwater resources is scarce. To fill this gap, the joint project “Effects of climate-adapted tree species selection on groundwater recharge” of the Federal Institute for Geosciences and Natural Resources (BGR) and the Northwest German Forest Research Institute (NW-FVA), funded by the Forest Climate Fund (WKF), aims at better understanding processes of groundwater recharge at six forest sites. The study sites comprise monoculture forest stands of European beech, Norway spruce, Douglas fir, Scots pine, red oak and pedunculate oak. To assess groundwater recharge rates, we performed D2O-tracer experiments on four sites since December 2022. At each site one plot of 4 m² was irrigated with 5 mm of D2O-labelled water (δ2H: 110 000 – 140 000 ‰). We will present the results of the tracer peak displacement until spring 2023 for each plot together with groundwater recharge estimates based on soil gravimetric water content and bulk dry density data. In addition, at two sites (red oak and Scots pine), these results will be compared to natural seasonal signals of stable isotopes in the soil water. Preliminary results of the red oak lowland forest site show that during summer 2022 seasonal signals reached down to 4 m depth and that gravimetric water contents dropped below 4 % for the entire mineral soil profile reaching down to the capillary fringe at 6.50 m.

Description: The flow dependent impact of multiple sources of uncertainty on convective precipitation is investigated in a consolidated way using the operational convection permitting ICON-D2 model in ensemble mode. Two model uncertainties -- microphysics (MP) and planetary boundary layer (PBL) turbulence --are considered in the presence of initial and lateral boundary condition uncertainties. The case studies are stratified based on the strength of synoptic control on convection. We found that model uncertainties act on different processes and spatiotemporal scales. MP uncertainty hardly has an impact on precipitation amounts at small spatiotemporal scales but influences daily accumulations. In contrast, the physically-based stochastic perturbations (PSP) in the PBL directly impact the diurnal cycle of precipitation. MP uncertainty only weakly impacts scales of O(100km), whereas the uncertainty in PBL significantly changes the spatial distribution at smaller scales at certain times. Those impacts on amounts and spatial distributions are more sensitive during weak synoptic control. The combination of various uncertainties adds further variability to forecast distributions and is potentially beneficial for improving the underdispersion of forecast spread of precipitation, especially during weak synoptic control.

Description: Recent years have seen an increase in the use of non-contact methods of river discharge estimation, which calls for the measurement of surface velocity in the top portion of the cross-section utilizing non-contact doppler radar sensors like Handheld or Mounted radars. Given the constrained and probabilistic character of the flow, these radars can be utilized to predict discharge based on the entropy theory. Additionally, a river section can be utilized to measure surface velocity at several predetermined verticals using the traditional area-velocity approach. One of the major prerequisites for the estimation of discharge through non-contact techniques is the characterization of the nature of the surface velocity profile at the section. The problem arises when the flow experiences large turbulence due to sidewall effects and other characteristics of the channel, especially in narrow mountainous channels. This study compares different velocity profiles for the measured surface velocity at several predefined verticals at two cross-sections of Bhagirathi and Ganga, two significant Himalayan rivers having widths of 30m and 60m respectively. . Three velocity profiles i.e. Elliptic, Parabolic, and Polynomial profiles obtained through the curve-fitting technique were compared based on error distribution and uncertainty analysis using Forecast Range Error Estimate method. Further, to determine which profile would be optimal for the selected segments, the measured mean velocity of current-meter was compared to the estimated mean velocity for each profile. The study offers a straightforward method for choosing the ideal surface velocity profile for a river by just measuring the surface velocity at predetermined verticals.

Description: The present study investigates the interannual variability of the tropical Indian Ocean (IO) based on the transfer routes of wave energy in a set of 61-yr hindcast experiments using a linear ocean model. To understand the basic feature of the IO dipole mode, this paper focuses on the 1994 pure positive event. Two sets of westward transfer episodes in the energy flux associated with Rossby waves (RWs) are identified along the equator during 1994. One set represents the same phase speed as the linear theory of equatorial RWs, while the other set is slightly slower than the theoretical phase speed. The first set originates from the reflection of equatorial Kelvin waves at the eastern boundary of the IO. On the other hand, the second set is found to be associated with off-equatorial RWs generated by southeasterly winds in the southeastern IO, which may account for the appearance of the slower group velocity. A combined empirical orthogonal function (EOF) analysis of energy-flux streamfunction and potential reveals the intense westward signals of energy flux are attributed to off-equatorial RWs associated with predominant wind input in the southeastern IO corresponding to the positive IO dipole event.

Description: Over the past years, with the rapid progress of Global Navigation Satellite System Interferometric Reflectometry (GNSS-IR) technique, near-shore geodetic GNSS receivers have been attempted to retrieve dynamic sea-level variation induced by storm surges and tsunamis. As the largest event since 1939, the 2023 M7.8 Turkiye earthquake not only caused terrifying building collapses on land but also generated observable tsunamis in the sea as recorded by coastal tide gauges. In this study, we thus try to verify the performance of GNSS-IR sea-level retrieval for tsunami monitoring based on GNSS data from IGS and TPGN(Turkish Permanent GNSS Network). Our preliminary findings show that, in spite of a continental strike-slip rupture, a tsunami with 30 cm wave height, following days of ocean resonance, is clearly seen by GNSS-IR, consistent with nearby tide gauge records. Furthermore, we also perform a finite source inversion to explore whether a submarine landslide contributes to the tsunami. Our work demonstrates the capability of GNSS-IR for detecting medium and small tsunamis accurately. In fact, such geodetic GNSS receivers have been now well-deployed for co-seismic displacement monitoring and fast earthquake source characterizing for tsunami early warning in many places in the world. If more receivers can be installed near-shore, without extra operational costs, such a network will extend our tsunami observation power and improve the robustness of the tsunami early warning system.

Description: On 30 October 2020 at 11:51 UT, a magnitude 7.0 earthquake occurred in the Dodecanese sea (37.84°N, 26.81°E, 10 km depth), that generated a tsunami with an observed run-up of more than 1 meter on the Turkish coasts. Both the earthquake and the tsunami produced acoustic and gravity waves that propagated upward, triggering co-seismic and co-tsunamic ionospheric disturbances. This paper presents a multi-instrumental study of the ionospheric impact of the earthquake and related tsunami based on ionosonde data, ground-based and Swarm-based GNSS receivers, and Jason3/DORIS [L1] receivers in the Mediterranean region. Our study focuses on the Total Electron Content derived from the European GNSS network, Swarm, and Jason3, to describe the propagation of Medium Scale Travelling Ionospheric Disturbances (MSTIDs), possibly related to gravity waves triggered by the earthquake and tsunami. We use simultaneous vertical ionosonde soundings to study the interactions between the upper and lower atmosphere. The results of this study provide a detailed picture of the Litosphere-Atmosphere-Ionosphere coupling in the scarcely investigated area that is the Mediterranean region.

Description: The tropical Angolan upwelling system (tAUS) is a highly productive ecosystem with a distinct seasonal variability with productivity peaking in austral winter. The tAUS is connected to equatorial dynamics via the propagation of equatorial and coastal trapped waves (CTWs). We use hydrographic, ocean turbulence and satellite data to investigate the role of CTWs in controlling the seasonal cycle of productivity in the tAUS. During austral winter associated with the passage of an upwelling CTW, the nitracline is displaced upward by about 50 m. Through this vertical advection nitrate-rich waters passes onto the shelf. Due to the elevated mixing rates on the shelf, this movement of the nitracline results an increased vertical nitrate flux into the ocean mixed layer. Our analysis further shows that interannual variability in the strength of the austral winter net primary production correlates with the amplitude of the seal level anomaly signal of the corresponding upwelling CTW. The signal of sea level depression leads the maximum productivity signal by about 40 days. It is suggested that this time lag arises, among other factors, from the vertical structure of the CTWs arriving in the tAUS. While the sea level anomaly is dominated by the faster low-baroclinic mode CTWs, the displacement of the nitracline is mainly influenced by the slower high-baroclinic mode CTWs that arrive later in the tAUS. Our results highlight the crucial role CTWs play for the productivity in the tAUS. The strong connection between equatorial dynamics and productivity further introduces a possibility for predicting interannual variability.

Description: The recent global MHD simulation code (REPPU code by Tanaka [2015]) successfully reproduces even observed phenomena such as the auroral breakup of the substorm. We judge that the simulation code correctly reproduces the physical processes of the magnetosphere and ionosphere from the fact that the phenomenon is reproduced realistically. REPPU code employs several empirical parameters expressing the non-MHD mechanisms. We tried to determine the optimal values of the parameters by using the data assimilation technique. For this purpose, we improve the REPPU code to include both the effect of the inclined rotation axis of the Earth and the effect of the discrepancy between the rotational axis and the magnetic axis. Next, we apply the data assimilation technique to determine the ionospheric conductivity distribution which is given as empirical parameters in the original REPPU code. For this purpose, we use the ionospheric electric potential determined by SuperDARN and AE indices. We employed the ensemble variational method as the assimilation technique to obtain the optimal values of the parameters. As a result, we obtained that the ionospheric conductivities are enhanced compared with the empirical results. At the same time, modification of the ionospheric conductivity does not change significantly the magnetosphere. The simulation data become the “reanalysis data” of the space weather which is useful for space weather research. Our future goal is to provide a database of the reanalysis data for space weather.

Description: Climatology, also named the "Climate Normal" by World Meteorological Organization (WMO), is critical for characterizing historical or near-future weather and climate states, and is usually calculated for a uniform 30-year period according to the WMO definitions. However, in addition to external forcing changes, climatology can be impacted by internal climate variabilities on multi-decadal and longer time scales. Here we introduce a simple sampling model and conduct three equilibrium climate sensitivity experiments using a Global Climate Model EC-Earth to quantify the potential uncertainties in estimating equilibrium climate change. We take into account the effect of multi-centennial variability in the climate system, which has been identified in paleo-climate proxy records and long climate model simulations. For the time series that contain multi-centennial oscillation, the estimate of climate change refers to the difference between two equilibrium climate states that may have significant uncertainty due to random selection of the phase location of the sampling. Our exercises with EC-Earth experiments show that such uncertainties are significant at high latitudes where low-frequency oscillations dominate. The accuracy of the estimated climate state at mid-to-high latitudes in the Northern Hemisphere is mainly impacted by the multi-centennial oscillation, while the uncertainty in mid-to-high Southern Hemisphere is affected by the oscillation on multi-centennial to millennial time scales. We show that applying quasi-periodic sampling in calculating the equilibrium climate state can significantly reduce such uncertainties. This work reminds us that the potential uncertainties induced by multi-centennial climate variability cannot be ignored when the length of sampling data is limited.

Description: The study examines the interannual relationship between the variability of sea ice extent in the Indian Ocean sector (20–90oE) and Indian summer monsoon rainfall under the influence of Mascarene High. Sea ice extent during April-May-June (AMJ) appears to have a significant correlation with the summer monsoon rainfall over the Peninsular India region during June-July-August-September from 1979 to 2013. We utilized reanalysis, satellite, and in-situ observation data from 1979 to 2013. The empirical orthogonal function (EOF) and correlation analysis show that the first and third modes of principal component (PC1 and PC3) of SIE in the Indian Ocean sector during April-May-June (AMJ) are significantly correlated with the second mode of principal component (PC2) of Indian summer monsoon rainfall. The reanalysis data revealed that the changes in the SIE in the Indian Ocean sector excite meridional wave train responses along the Indian Ocean for both principal component modes. Positive (negative) SIE anomalies based on first and third EOFs (EOF1 and EOF3) contribute to the strengthening (weakening) of the Polar, Ferrel, and Hadley cells, inducing stronger (weaker) convective activity over the Indian latitudes. The weak (strong) convective activity over the Indian region leads to less (more) rainfall over the region during low (high) sea ice phase years. Furthermore, a weaker (stronger) polar jet during the low (high) sea ice phase is also noted.

Description: Frequency of extreme rainfalls and snowfalls has been increasing these years, and those events severely affect human lives and properties. It has been considered that tropical ocean and atmosphere variability as well as the warming climate, remotely influences mid-latitude extreme weather/climate, while the mid-latitude ocean is passive to atmospheric variability. Recent high-resolution ocean/atmospheric data analyses, however, have revealed that mid-latitude ocean also influences atmospheric circulations and their variability. Rediscovering strong warm current and associated strong ocean frontal zones as “climate hotspot”, we have elucidated mechanisms of ocean-atmosphere interactions. The research progress has prompted a new crucial task: application of such new knowledge to predictions of extreme rainfalls/snowfalls and climate variability. For the new task, in the five-year research project called “Climatic Hotspot2” from 2019, we have conducted studies to further our understandings of mid-latitude ocean-atmosphere interaction processes. In the project, several observation campaigns and also oceanic and atmospheric high-resolution numerical modeling studies have been conducted. Those studies have revealed crucial influence of ocean currents and oceanic structures on climate extreme events. In this presentation, we introduce results of the projects, including predictability of the Kuroshio Extension and Gulf Stream jet speeds and eddy activities around them. This presentation is co-authored with the Climatic Hotspot2 group.

Description: Direct observations of sunspots exist for the past four centuries while proxy based reconstructions exist for thousands of years. Over a significant fraction of the past century, records of sunspot tilt angles and areas have also been collected. These observations provide a means to understand the physics of long-term solar variability by discriminating between various models of the solar cycle. In this talk, I shall discuss how the synergy of solar surface flux transport modelling, dynamo modelling and solar activity observations have led us to the conclusion that the primary driver for decadal-scale variability in the solar cycle is imbibed in the Babcock-Leighton mechanism for poloidal field generation which is governed by the emergence of tilted bipolar sunspot pairs and their subsequent evolution driven by flux transport processes. I shall also highlight what this emergent understanding implies for solar cycle 25 forecasts.

Description: Upper-ocean fronts are dynamically active features of the global ocean that have significant implications for air-sea interactions, vertical mass and heat transfers, stratification and phytoplankton production and export. Their small dimensions and short duration have limited our capacity of observing, modelling and understanding fully these processes and their impact. To address this challenge, five Saildrones - which are uncrewed platforms instrumented to measure the air-sea interface – were deployed during the EUREC4A-OA/ATOMIC field experiment in the Northwest Tropical Atlantic in winter 2020. This region is strongly affected by the outflow of the Amazon River, leading to the generation of fine-scale horizontal thermohaline gradients with the stirring of this freshwater input by large anticyclonic eddies. Very intense gradients, including at the smaller spatial scales, were measured. The coherence of temperature and salinity fronts was estimated by a wavelet transform analysis which revealed large-scale density fronts are primarily controlled by salinity but with increasing temperature-salinity coherence at the small scales range of the spectrum (O (0.1 km)) for strong gradients whereas they are poorly correlated for weaker fronts. Our study shows that processes such as the mixed layer depth, the diurnal cycle, and air-sea exchanges are strongly affected by these small-scale frontal regimes. The parallel and quasi synchronous tracks of a 4-Saildrone formation provide a detailed picture of the upper ocean vorticity, divergence, and strain from their ADCP current measurements. Overall the methodology developed could be extended on other datasets to assess the phenomenology of fine-scale structures in other dynamical regions.