ALBERT

Beschreibung: Several episodes of extreme precipitation excess and extreme precipitation deficit, with considerable economic and social impacts, have occurred in Europe and in Poland in the last decades. However, the changes of related indices exhibit complex variability. This paper analyses changes in indices related to observed abundance and deficit of precipitated water in Poland. Among studied indices are maximum seasonal 24-h precipitation for the winter half-year (Oct.–March) and the summer half-year (Apr.–Sept.), maximum 5-day precipitation, maximum monthly precipitation and number of days with intense or very intense precipitation (respectively, in excess of 10 mm or 20 mm per day). Also, the warm-seasonal maximum number of consecutive dry days (longest period with daily precipitation below 1 mm) was examined. Analysis of precipitation extremes showed that daily maximum precipitation for the summer half-year increased for many stations, and increases during the summer half-year are more numerous than those in the winter half-year. Also, analysis of 5-day and monthly precipitation sums show increases for many stations. Number of days with intense precipitation increases especially in the north-western part of Poland. The number of consecutive dry days is getting higher for many stations in the summer half-year. Comparison of these two periods: colder 1961–1990 and warmer 1991–2015, revealed that during last 25 years most of statistical indices, such as 25th and 75th percentiles, median, mean and maximum are higher. However, many changes discussed in this paper are weak and statistically insignificant. The findings reported in this paper challenge results based on earlier data that do not include 2007–2015.

Beschreibung: Household food security among smallholder farmers is sensitive to a variable and changing climate, requiring farmers in the Gamo Highlands of Ethiopia to adopt new land management practices to improve food security. Agricultural land in the Gamo Highlands is highly fragmented. The extent to which land fragmentation (LF) moderates the food security effects of sustainable land management (SLM) practices is unknown. This study used probit and Poisson models to explain this relationship. The study found that food insecurity was severe during the food shortfall season. LF provides more potential opportunities for improving food security than challenges. Furthermore, SLM practices had both positive and negative effects on food security and their effects were conditioned by the magnitude of LF. Reducing severe LF through the assembly of small parcels into larger heterogeneous plot clusters could enhance food security by exploiting synergies between adaptation practices and LF.

Beschreibung: The summer of 2018 witnessed a number of extreme weather events such as heatwaves in North America, Western Europe and the Caspian Sea region, and rainfall extremes in South-East Europe and Japan that occurred near-simultaneously. Here we show that some of these extremes were connected by an amplified hemisphere-wide wavenumber 7 circulation pattern. We show that this pattern constitutes an important teleconnection in Northern Hemisphere summer associated with prolonged and above-normal temperatures in North America, Western Europe and the Caspian Sea region. This pattern was also observed during the European heatwaves of 2003, 2006 and 2015 among others. We show that the occurrence of this wave 7 pattern has increased over recent decades.

Beschreibung: Larger forest patches in urban areas are highly valuable recreation sites that provide the urban population with various ecosystem services. Yet they are highly vulnerable to biological pests, especially in the light of climate change. The growing need to intervene against forest pests needs to be clearly but carefully communicated to the urban forest visitors in order to minimize conflicts. In this paper, a survey with 554 complete responses, conducted in the forest district of the “Teufelssee” in south-east Berlin, Germany, sheds first light on visitors’ perceptions of biological pests and their management. Results of Chi square statistics and a series of Logit models indicate a clear predisposition against pesticide or biocide interventions, while at the same time, showing remarkable positive tendencies towards mechanical interventions or measures taken on the individual-tree level. There are positive correlations between the age and the knowledge about pests (Kendall-Tau-b τB = 0.165) and between the age and the knowledge about pest regulation (τB = 0.182). Positive correlations also exist between level of education and pest knowledge (τB = 0.1) and knowledge about their regulation (τB = 0.08), respectively. Elderly respondents tend to vote for faster interventions. Overall, a large majority of the respondents would be willing to participate in a volunteer mapping of pests while visiting the forest. The results of this study can be used to inform urban forest management to modify and optimize their communication and information policies concerning pests and substantiated interventions.

Beschreibung: A rapid and deep decarbonization of power supply worldwide is required to limit global warming to well below 2 °C. Beyond greenhouse gas emissions, the power sector is also responsible for numerous other environmental impacts. Here we combine scenarios from integrated assessment models with a forward-looking life-cycle assessment to explore how alternative technology choices in power sector decarbonization pathways compare in terms of non-climate environmental impacts at the system level. While all decarbonization pathways yield major environmental co-benefits, we find that the scale of co-benefits as well as profiles of adverse side-effects depend strongly on technology choice. Mitigation scenarios focusing on wind and solar power are more effective in reducing human health impacts compared to those with low renewable energy, while inducing a more pronounced shift away from fossil and toward mineral resource depletion. Conversely, non-climate ecosystem damages are highly uncertain but tend to increase, chiefly due to land requirements for bioenergy.

Beschreibung: Background Anemia affects ∼1.6 billion people worldwide, often owing to iron deficiency. In Bangladesh, high levels of anemia have been observed alongside little iron deficiency. Elevated concentrations of groundwater iron could constitute a significant source of dietary iron. Objective We aimed to quantify the effect of groundwater iron on anemia in nonpregnant women and young children in Bangladesh, taking into account dietary factors that may affect iron absorption. Methods We analyzed data on 1871 nonpregnant women and 987 children (6–37 mo) from the 2015 baseline survey of the Food and Agricultural Approaches to Reducing Malnutrition cluster-randomized trial in Sylhet, Bangladesh. We used logistic regression with robust standard errors to assess effects of self-reported groundwater iron, dietary intake, and sociodemographic characteristics on anemia, considering interactions between groundwater iron and dietary factors. Results Groundwater iron presence was associated with less anemia in women (OR: 0.74; 95% CI: 0.60, 0.90) and children (OR: 0.58; 95% CI: 0.44, 0.76). This effect was modified by dietary factors. In women, the effect of groundwater iron on anemia was stronger if no vitamin C–rich or heme-iron foods were consumed, and there was a clear dose–response relation. In children, intake of vitamin C–rich foods strengthened the effect of groundwater iron on anemia, and there was no evidence for interaction by intake of iron-rich foods. Conclusions Heme-iron and vitamin C consumption reduced the effect of groundwater iron on anemia among women but not children in Bangladesh, which may be due to higher levels of iron deficiency and lower levels of iron intake among children. Vitamin C consumption appears to enhance iron absorption from groundwater in children and they may thus benefit from consuming more vitamin C–rich fruits and vegetables. Even among women and children consuming heme-iron or vitamin C–rich foods and groundwater iron, anemia prevalence remained elevated, pointing to additional causes of anemia beyond iron deficiency. This trial was registered at clinicaltrials.gov as NCT02505711.

Beschreibung: The oceans and atmosphere interact via a multiplicity of feedback mechanisms, shaping to a large extent the global climate and its variability. To deepen our knowledge of the global climate system, characterizing and investigating this interdependence is an important task of contemporary research. However, our present understanding of the underlying large-scale processes is greatly limited due to the manifold interactions between essential climatic variables at different temporal scales. To address this problem, we here propose to extend the application of complex network techniques to capture the interdependence between global fields of sea-surface temperature (SST) and precipitation (P) at multiple temporal scales. For this purpose, we combine time-scale decomposition by means of a discrete wavelet transform with the concept of coupled climate network analysis. Our results demonstrate the potential of the proposed approach to unravel the scale-specific interdependences between atmosphere and ocean and, thus, shed light on the emerging multiscale processes inherent to the climate system, which traditionally remain undiscovered when investigating the system only at the native resolution of existing climate data sets. Moreover, we show how the relevant spatial interdependence structures between SST and P evolve across time-scales. Most notably, the strongest mutual correlations between SST and P at annual scale (8–16 months) concentrate mainly over the Pacific Ocean, while the corresponding spatial patterns progressively disappear when moving toward longer time-scales. The study of the climate system using complex networks provides new insights into spatiotemporal climate dynamics. Most previous studies have focused on a single climate variable only. Accounting for the multivariate and multiscale nature of climate variability introduces a new challenging perspective that could help improve our understanding of the underlying physical mechanisms. In this study, we focus on the aforementioned two aspects of multiple variables and time-scales contributing to the variability of the climate system and show that cross-variable statistical relations evolve differently at different time-scales. Consideration of this previously widely disregarded factor provides a more explicit picture of scale-dependent covariability patterns among climate variables and their temporal evolution, which might be overlooked when focusing only at the native resolution of existing climate data sets

Beschreibung: In manifold ways science and practice are working together to find solutions for sustainable land management. New research programmes on this topic generate a large variety of single project results. Accompanying research projects will realize additional value by merging and synthesising the results from these projects and by supporting the generation of new knowledge for science and society. For many actors in science and policy, the additional value of research accompanying research projects remains open. Referring to a recent publication in GAIA that introduces a typology for accompanying research (AR), this article discusses the central issues, content, processes and ongoing challenges in an AR project accompanying the German research programme Sustainable Land Management. The important value of AR can be seen in communication, networking, the reflexive generation of new knowledge and knowledge management based on trust building and competence. AR also exhibits great potential for research on cross-cutting issues in research programmes and has special significance for meta-studies on different research projects taking place under similar funding conditions. However, additional analyses are necessary for a better understanding of the outcomes and impacts of AR and to create wider appreciation and acceptance.

Beschreibung: Here we present preliminary experimental data suggesting about involvement of the meningeal and cervical lymphatics in neurorehabilitation. Using model of hemorrhagic stroke, immunohistochemical analysis and atomic absorption spectroscopy, we clearly demonstrate the lymphatic clearance from the blood after stroke via the meningeal lymphatic vessels with further accumulation of hemosiderin and iron (products of disaggregated hemoglobin) in the deep cervical node (dcLN). The optical coherent tomography (OCT) was used for in vivo monitoring of accumulation of gold nanorods (92 nm in diameter) in the dcLN after their injection into the cisterna magna with the aim of mimicking of the brain clearance from of blood. The both ex vivo and in vivo data show the lymphatic clearance from subjects (the blood/GNRs) injected into the subarachnoid space that might be an important mechanism of neurorehabilitation after the intracranial hemorrhages.

Beschreibung: The Sustainable Development Goals (SDGs) and the Paris Agreement on Climate Change call for deep transformations in every country that will require complementary actions by governments, civil society, science and business. Yet stakeholders lack a shared understanding of how the 17 SDGs can be operationalized. Drawing on earlier work by The World in 2050 initiative, we introduce six SDG Transformations as modular building-blocks of SDG achievement: (1) education, gender and inequality; (2) health, well-being and demography; (3) energy decarbonization and sustainable industry; (4) sustainable food, land, water and oceans; (5) sustainable cities and communities; and (6) digital revolution for sustainable development. Each Transformation identifies priority investments and regulatory challenges, calling for actions by well-defined parts of government working with business and civil society. Transformations may therefore be operationalized within the structures of government while respecting the strong interdependencies across the 17 SDGs. We also outline an action agenda for science to provide the knowledge required for designing, implementing and monitoring the SDG Transformations.

Beschreibung: We use the flexible model coupling technology known as the bespoke framework generator to link established existing modules representing dynamics in the global economy (GEMINI_E3), the energy system (TIAM-WORLD), the global and regional climate system (MAGICC6, PLASIM-ENTS and ClimGEN), the agricultural system, the hydrological system and ecosystems (LPJmL), together in a single integrated assessment modelling (IAM) framework, building on the pre-existing framework of the Community Integrated Assessment System. Next, we demonstrate the application of the framework to produce policy-relevant scientific information. We use it to show that when using carbon price mechanisms to induce a transition from a high-carbon to a low-carbon economy, prices can be minimised if policy action is taken early, if burden sharing regimes are used, and if agriculture is intensified. Some of the coupled models have been made available for use at a secure and user-friendly web portal.

Beschreibung: Wheat grain protein concentration is an important determinant of wheat quality for human nutrition that is often overlooked in efforts to improve crop production. We tested and applied a 32‐multi‐model ensemble to simulate global wheat yield and quality in a changing climate. Potential benefits of elevated atmospheric CO2 concentration by 2050 on global wheat grain and protein yield are likely to be negated by impacts from rising temperature and changes in rainfall, but with considerable disparities between regions. Grain and protein yields are expected to be lower and more variable in most low‐rainfall regions, with nitrogen availability limiting growth stimulus from elevated CO2. Introducing genotypes adapted to warmer temperatures (and also considering changes in CO2 and rainfall) could boost global wheat yield by 7% and protein yield by 2%, but grain protein concentration would be reduced by −1.1 percentage points, representing a relative change of −8.6%. Climate change adaptations that benefit grain yield are not always positive for grain quality, putting additional pressure on global wheat production.

Beschreibung: Forward flux sampling (FFS) has provided a convenient and efficient way to simulate rare events in equilibrium as well as non-equilibrium stochastic systems. In the present paper, the FFS scheme is applied to systems driven by colored Gaussian noise through enlarging the dimension to deal with the non-Markovian property. Besides, the parameters of the FFS scheme have to be reconsidered. Interestingly, by analyzing the effect of colored Gaussian noise on stationary distributions, some results are found which are clearly different from the case of Gaussian white noise excitation. We mainly found that the probability of the occurrence of rare events is inversely proportional to the correlation time. Comparing to the case of Gaussian white noise with the same intensity, the presence of colored Gaussian noise exerts a hindrance to the occurrence of rare events. Meanwhile, the FFS results show a good agreement with those from Monte Carlo simulations, even for the colored Gaussian noise case. This provides a potential insight into rare events of systems under non-white Gaussian noise via the FFS scheme.

Beschreibung: Increasingly complex nonlinear World-Earth system models are used for describing the dynamics of the biophysical Earth system and the socioeconomic and sociocultural World of human societies and their interactions. Identifying pathways toward a sustainable future in these models for informing policymakers and the wider public, e.g., pathways leading to robust mitigation of dangerous anthropogenic climate change, is a challenging and widely investigated task in the field of climate research and broader Earth system science. This problem is particularly difficult when constraints on avoiding transgressions of planetary boundaries and social foundations need to be taken into account. In this work, we propose to combine recently developed machine learning techniques, namely, deep reinforcement learning (DRL), with classical analysis of trajectories in the World-Earth system. Based on the concept of the agent-environment interface, we develop an agent that is generally able to act and learn in variable manageable environment models of the Earth system. We demonstrate the potential of our framework by applying DRL algorithms to two stylized World-Earth system models. Conceptually, we explore thereby the feasibility of finding novel global governance policies leading into a safe and just operating space constrained by certain planetary and socioeconomic boundaries. The artificially intelligent agent learns that the timing of a specific mix of taxing carbon emissions and subsidies on renewables is of crucial relevance for finding World-Earth system trajectories that are sustainable in the long term. We propose a framework for using deep reinforcement learning (DRL) as an approach to extend the field of Earth system analysis by a new method. We build our framework upon the agent-environment interface concept. The agent can apply management options to models of the Earth system as the environment of interest and learn by rewards provided by the environment. We train our agent with a deep Q-neural network extended by current state-of-the-art algorithms. We find that the agent is able to learn novel, previously undiscovered policies that navigate the system into sustainable regions in two exemplary conceptual models of the World-Earth system.

Beschreibung: We present a novel and an efficient way to mitigate oscillatory instability in turbulent reactive flows. First, we construct weighted spatial correlation networks from the velocity field obtained from high-speed particle image velocimetry. Using network measures, we identify the optimal location for implementing passive control strategies. By injecting micro-jets at this optimal location, we are able to reduce the amplitude of the pressure oscillations to a value comparable to what is observed during the state of stable operation. This approach opens up new avenues to control oscillatory instabilities in turbulent flows.

Beschreibung: Ten years ago, Johan Rockström identified nine limits for Earth's life-support systems. We have already exceeded four of them, but he is still cautiously optimistic for our future, he tells Fred Pearce

Beschreibung: Comparing paleoclimate time series is complicated by a variety of typical features, including irregular sampling, age model uncertainty (e.g., errors due to interpolation between radiocarbon sampling points) and time uncertainty (uncertainty in calibration), which—taken together—result in unequal and uncertain observation times of the individual time series to be correlated. Several methods have been proposed to approximate the joint probability distribution needed to estimate correlations, most of which rely either on interpolation or temporal downsampling. Here, we compare the performance of some popular approximation methods using synthetic data resembling common properties of real world marine sediment records. Correlations are determined by estimating the parameters of a bivariate Gaussian model from the data using Markov Chain Monte Carlo sampling. We complement our pseudoproxy experiments by applying the same methodology to a pair of marine benthic O records from the Atlantic Ocean. We find that methods based upon interpolation yield better results in terms of precision and accuracy than those which reduce the number of observations. In all cases, the specific characteristics of the studied time series are, however, more important than the choice of a particular interpolation method. Relevant features include the number of observations, the persistence of each record, and the imposed coupling strength between the paired series. In most of our pseudoproxy experiments, uncertainty in observation times introduces less additional uncertainty than unequal sampling and errors in observation times do. Thus, it can be reasonable to rely on published time scales as long as calibration uncertainties are not known.

Beschreibung: Comprehensive and robust statistical estimates of trends during heavy precipitation events are essential in understanding the impact of past and future climate changes in the hydrological cycle. However, methods commonly used in extreme value statistics (EVS) are often unable to detect significant trends, because of their methodologically motivated reduction of the sample size and strong assumptions regarding the underlying distribution. Here, we propose linear quantile regression (QR) as a complementary and robust alternative to estimating trends in heavy precipitation events. QR does not require any assumptions on the underlying distribution and is also able to estimate trends for the full span of the distribution without any reduction of the available data. As an example, we study here a very dense and homogenized data set of daily precipitation amounts over Germany for the period between 1951 and 2006 to compare the results of QR and the so-called block maxima approach, a classical method in EVS. Both methods indicate an overall increase in the intensity of heavy precipitation events. The strongest trends can be found in regions with an elevation of about 500 m above sea level. In turn, larger spatial clusters of moderate or even decreasing trends can only be found in Northeastern Germany. In conclusion, both methods show comparable results. QR, however, allows for a more flexible and comprehensive study of precipitation events.

Beschreibung: Using a newly developed model approach and combining it with remote sensing, population, and climate data, first insights are provided into how local diets, urbanisation, and climate change relates to local urban food self-sufficiency. In plain terms, by utilizing the global peri-urban (PU) food production potential approximately 1bn urban residents (30% of global urban population) can be locally nourished, whereby further urbanisation is by far the largest pressure factor on PU agriculture, followed by a change of diets, and climate change. A simple global food transport model which optimizes transport and neglects differences in local emission intensities indicates that CO2 emissions related to food transport can be reduced by a factor of 10.

Beschreibung: Green fiscal reforms would contribute to climate change mitigation, increase the economic efficiency of national tax systems and provide additional public revenues. Some countries in Latin America have already taken first steps towards green fiscal reforms. This outlook article provides an overview of the major challenges for the successful implementation of such reforms and discusses how they could be overcome.

Beschreibung: Climate projections1,2,3 and observations over recent decades4,5 indicate that precipitation in subtropical latitudes declines in response to anthropogenic warming, with significant implications for food production and population sustainability. However, this conclusion is derived from emissions scenarios with rapidly increasing radiative forcing to the year 21001,2, which may represent very different conditions from both past and future ‘equilibrium’ warmer climates. Here, we examine multi-century future climate simulations and show that in the Southern Hemisphere subtropical drying ceases soon after global temperature stabilizes. Our results suggest that twenty-first century Southern Hemisphere subtropical drying is not a feature of warm climates per se, but is primarily a response to rapidly rising forcing and global temperatures, as tropical sea-surface temperatures rise more than southern subtropical sea-surface temperatures under transient warming. Subtropical drying may therefore be a temporary response to rapid warming: as greenhouse gas concentrations and global temperatures stabilize, Southern Hemisphere subtropical regions may experience positive precipitation trends.

Beschreibung: Secondary or onward mobility of refugees can pose considerable challenges for targeted and timely humanitarian assistance, and for long-term integration. There is very little systematic knowledge of the onward migration of refugees after their initial flight to a country of reception in general, and specifically in Turkey. In this chapter, we describe how the analysis of mobile phone Call Details Records can help to better understand spatio-temporal patterns of refugees’ onwards mobility. The analysis reveals some clear, large-scale mobility patterns (from South to North, from East to West, from Centre to the Coast, to large urban areas), and also some temporal patterns, but also shows that human mobility is complex and accordingly requires more advanced analytical tools. We conclude that it might be worth of re-framing registration policies for refugees, given the highly mobile share of refugee population, and the important role that this mobility probably plays for livelihoods.

Beschreibung: The Global Gridded Crop Model Intercomparison (GGCMI) phase 1 dataset of the Agricultural Model Intercomparison and Improvement Project (AgMIP) provides an unprecedentedly large dataset of crop model simulations covering the global ice-free land surface. The dataset consists of annual data fields at a spatial resolution of 0.5 arc-degree longitude and latitude. Fourteen crop modeling groups provided output for up to 11 historical input datasets spanning 1901 to 2012, and for up to three different management harmonization levels. Each group submitted data for up to 15 different crops and for up to 14 output variables. All simulations were conducted for purely rainfed and near-perfectly irrigated conditions on all land areas irrespective of whether the crop or irrigation system is currently used there. With the publication of the GGCMI phase 1 dataset we aim to promote further analyses and understanding of crop model performance, potential relationships between productivity and environmental impacts, and insights on how to further improve global gridded crop model frameworks. We describe dataset characteristics and individual model setup narratives.

Beschreibung: The study of the ecosphere, that is, the biosphere-geosphere complex, needs to be complemented by the consideration of the anthroposphere in order to achieve a thorough understanding of its large scale context. The (inter)discipline aiming at achieving this completion is Earth System Science. It is directed at our planet as a whole, with its seemingly endless complexity, weaving together the interacting physical, chemical, biological and not the least human components. It is revolutionary because it again places us, humanity, in a new context: our presence and our activities on Earth have shifted, altered and even destroyed multiple elements of the system or interaction pathways. We are on the verge of triggering large-scale regime shifts, of which climate change is undoubtedly the most dangerous one. In other words: The anthroposphere is now dominating the ecosphere. Science has produced some topical results recently, including on tipping elements of the Earth System, ocean acidification and glacial cycles. Welcome to the Anthropocene!

Beschreibung: Evidence suggests that global maize yield declines with a warming climate, particularly with extreme heat events. However, the degree to which important maize processes such as biomass growth rate, growing season length (GSL) and grain formation are impacted by an increase in temperature is uncertain. Such knowledge is necessary to understand yield responses and develop crop adaptation strategies under warmer climate. Here crop models, satellite observations, survey, and field data were integrated to investigate how high temperature stress influences maize yield in the U.S. Midwest. We showed that both observational evidence and crop model ensemble mean (MEM) suggests the nonlinear sensitivity in yield was driven by the intensified sensitivity of harvest index (HI), but MEM underestimated the warming effects through HI and overstated the effects through GSL. Further analysis showed that the intensified sensitivity in HI mainly results from a greater sensitivity of yield to high temperature stress during the grain filling period, which explained more than half of the yield reduction. When warming effects were decomposed into direct heat stress and indirect water stress (WS), observational data suggest that yield is more reduced by direct heat stress (−4.6 ± 1.0%/°C) than by WS (−1.7 ± 0.65%/°C), whereas MEM gives opposite results. This discrepancy implies that yield reduction by heat stress is underestimated, whereas the yield benefit of increasing atmospheric CO2 might be overestimated in crop models, because elevated CO2 brings yield benefit through water conservation effect but produces limited benefit over heat stress. Our analysis through integrating data and crop models suggests that future adaptation strategies should be targeted at the heat stress during grain formation and changes in agricultural management need to be better accounted for to adequately estimate the effects of heat stress.

Beschreibung: Human mortality shows a pronounced temperature dependence. The minimum mortality temperature (MMT) as a characteristic point of the temperature-mortality relationship is influenced by many factors. As MMT estimates are based on case studies, they are sporadic, limited to data-rich regions, and their drivers have not yet been clearly identified across case studies. This impedes the elaboration of spatially comprehensive impact studies on heat-related mortality and hampers the temporal transfer required to assess climate change impacts. Using 400 MMTs from cities, we systematically establish a generalised model that is able to estimate MMTs (in daily apparent temperature) for cities, based on a set of climatic, topographic and socio-economic drivers. A sigmoid model prevailed against alternative model setups due to having the lowest Akaike Information Criterion (AICc) and the smallest RMSE. We find the long-term climate, the elevation, and the socio-economy to be relevant drivers of our MMT sample within the non-linear parametric regression model. A first model application estimated MMTs for 599 European cities (〉100 000 inhabitants) and reveals a pronounced decrease in MMTs (27.8–16 °C) from southern to northern cities. Disruptions of this pattern across regions of similar mean temperatures can be explained by socio-economic standards as noted for central eastern Europe. Our alternative method allows to approximate MMTs independently from the availability of daily mortality records. For the first time, a quantification of climatic and non-climatic MMT drivers has been achieved, which allows to consider changes in socio-economic conditions and climate. This work contributes to the comparability among MMTs beyond location-specific and regional limits and, hence, towards a spatially comprehensive impact assessment for heat-related mortality.

Beschreibung: 2015 was a year of important milestones for Earth’s climate. Atmospheric carbon dioxide concentrations exceeded the level of 400 ppm for the first time in human history, global temperatures were more than 1 °C above pre-industrial levels for the first time, and, finally, the 2015 United Nations Climate Change Conference (or COP21) in Paris ended with the signing of a global agreement to safeguard Earth’s climate. In this chapter, I will briefly review the current state of global warming, the projected temperature increase and expected climate impacts in the future as well as the main elements of the Paris Agreement and its implications.

Beschreibung: Durch die Erwärmung der Erde werden besonders starke Stürme zusätzlich mit Energie aufgeladen. Experten diskutieren bereits, ob eine neue, höhere Kategorie für Hurrikane eingeführt werden soll.

Beschreibung: The Paris Agreement introduced an ambitious goal of limiting warming to 1.5 °C above pre-industrial levels. Here we combine a review of modelled pathways and literature on mitigation strategies, and develop a land-sector roadmap of priority measures and regions that can help to achieve the 1.5 °C temperature goal. Transforming the land sector and deploying measures in agriculture, forestry, wetlands and bioenergy could feasibly and sustainably contribute about 30%, or 15 billion tonnes of carbon dioxide equivalent (GtCO2e) per year, of the global mitigation needed in 2050 to deliver on the 1.5 °C target, but it will require substantially more effort than the 2 °C target. Risks and barriers must be addressed and incentives will be necessary to scale up mitigation while maximizing sustainable development, food security and environmental co-benefits.

Beschreibung: A global uniform carbon price would be economically efficient and at the same time avoid ‘carbon-leakage’. Still, it will affect the competitiveness of specific industries, economic activity and employment across countries. This paper assesses short-term economic shocks following the introduction of a global carbon price that would be in line with the Paris Agreement. Based on the World Input-Output Database (WIOD), we trace the carbon content of final output through global supply chains. This allows us to estimate how prices of the final output would react to the introduction of a global carbon price. We find that impacts on industrial competitiveness are highly heterogeneous across regions and economic sectors. The competitive position of Brazil, Japan, the USA and advanced economies of the EU is likely to improve, whereas industries and labor markets in newly industrializing Asian economies as well as Eastern Europe are likely to experience substantial adverse impacts.

Beschreibung: Recurrence Quantification Analysis (RQA) defines a number of quantifiers, which base upon diagonal line structures in the recurrence plot (RP). Due to the finite size of an RP, these lines can be cut by the borders of the RP and, thus, bias the length distribution of diagonal lines and, consequently, the line based RQA measures. In this letter we investigate the impact of the mentioned border effects and of the thickening of diagonal lines in an RP (caused by tangential motion) on the estimation of the diagonal line length distribution, quantified by its entropy. Although a relation to the Lyapunov spectrum is theoretically expected, the mentioned entropy yields contradictory results in many studies. Here we summarize correction schemes for both, the border effects and the tangential motion and systematically compare them to methods from the literature. We show that these corrections lead to the expected behavior of the diagonal line length entropy, in particular meaning zero values in case of a regular motion and positive values for chaotic motion. Moreover, we test these methods under noisy conditions, in order to supply practical tools for applied statistical research.

Beschreibung: Study region Tisza and Prut catchments, originating on the slopes of the Carpathian mountains. Study focus The study reported here investigates (i) climate change impacts on flood risk in the region, and (ii) uncertainty related to hydrological modelling, downscaling techniques and climate projections. The climate projections used in the study were derived from five GCMs, downscaled either dynamically with RCMs or with the statistical downscaling model XDS. The resulting climate change scenarios were applied to drive the eco-hydrological model SWIM, which was calibrated and validated for the catchments in advance using observed climate and hydrological data. The changes in the 30-year flood hazards and 98 and 95 percentiles of discharge were evaluated for the far future period (2071–2100) in comparison with the reference period (1981–2010). New hydrological insights for the region The majority of model outputs under RCP 4.5 show a small to strong increase of the 30-year flood level in the Tisza ranging from 4.5% to 62%, and moderate increase in the Prut ranging from 11% to 22%. The impact results under RCP 8.5 are more uncertain with changes in both directions due to high uncertainties in GCM-RCM climate projections, downscaling methods and the low density of available climate stations.

Beschreibung: Archetypes are increasingly used as a methodological approach to understand recurrent patterns in variables and processes that shape the sustainability of social-ecological systems. The rapid growth and diversification of archetype analyses has generated variations, inconsistencies, and confusion about the meanings, potential, and limitations of archetypes. Based on a systematic review, a survey, and a workshop series, we provide a consolidated perspective on the core features and diverse meanings of archetype analysis in sustainability research, the motivations behind it, and its policy relevance. We identify three core features of archetype analysis: recurrent patterns, multiple models, and intermediate abstraction. Two gradients help to apprehend the variety of meanings of archetype analysis that sustainability researchers have developed: (1) understanding archetypes as building blocks or as case typologies and (2) using archetypes for pattern recognition, diagnosis, or scenario development. We demonstrate how archetype analysis has been used to synthesize results from case studies, bridge the gap between global narratives and local realities, foster methodological interplay, and transfer knowledge about sustainability strategies across cases. We also critically examine the potential and limitations of archetype analysis in supporting evidence-based policy making through context-sensitive generalizations with case-level empirical validity. Finally, we identify future priorities, with a view to leveraging the full potential of archetype analysis for supporting sustainable development.

Beschreibung: Groundwater overdraft has affected sustainable development, especially in North and Coastal China, since the 1960s. The Chinese government instituted the Pilot Project of Groundwater Overexploitation Control (PPGOC) in Hebei Province during 2014 to 2016. This project introduced a set of hydrological, agricultural and administrative activities to recover the aquifer in the pilot area. In order to evaluate the effects of these activities on the groundwater status, a series of Data Envelopment Analysis (DEA) models are assembled as a model group and applied to calculate the relative performance of groundwater recovery units, i.e. the recovery efficiency in 49 counties or Decision-Making Units (DMUs). It is shown that the DEA model group can be used to evaluate the recovery efficiency, improve the performance of units not on the DEA frontier via radial and slack movement, and study the possibility of cost reduction. The result shows that 20 DMUs formed the frontier, which is the collective of the efficient DMUs, and that another 29 DMUs require efficiency improvement. The high efficiency of certain DMUs is related to the location and farmers' responses, which indicates that groundwater overdraft recovery is a technical problem that also has something to do with social and economic development and comprehensive governance. The model group can be used as a reference in the forthcoming implementation of aquifer recovery in groundwater overdraft zones in North and Coastal China.

Beschreibung: Soil data requirements and soil data acquisition tools and techniques have changed over recent decades. In general, soil scientists can: i) collect new data in the field and ignore the data that are available, ii) rely entirely on legacy soil data or iii) combine available legacy data with new data collection. This study aims to analyse and discuss the choices soil scientists make to balance between the use of legacy soil data and the collection of new soil data. A literature review on soil data acquisition was carried out and illustrated that the use of legacy soil data is still often very limited, while soil data availability increased over recent decades. Studies that use legacy soil data often use conventional soil data, which are criticised in literature. A regional and local case study was carried out to illustrate the choices that have to be made for obtaining the required soil data. It turned out that both case studies preferred to combine new soil data collection and legacy soil data. Many of the reviewed studies could reduce their sampling effort by making better use of available data, tools and techniques. Besides, soil scientists can help facilitating soil data acquisition by developing soil data warehouses.

Beschreibung: In the past decades, the Antarctic sea ice extent (SIE) has been steadily increasing, but recently showed a sharp decline. Here we address the questions whether (1) the observed changes in the Antarctic SIE can be fully explained by natural variability and (2) whether the recent unprecedented decline in the SIE can serve as an indication that the long-term positive trend has reached a turning point entailing further decline. To study these questions, we extended the analysis period of previous studies (until 2013) by considering data until May 2018 and applied a statistical model which accurately reflects the natural variability of the SIE. Contrary to earlier detection studies we find that none of the annual trends of the SIE in whole Antarctica and its five sectors are statistically significant. When studying the seasonal changes, we find that the only trends in the Antarctic SIE that cannot be explained by natural variability and are probably tied to the warming of the Antarctic Peninsula, are the negative trends of the SIE in austral autumn (p=0.043) and February (p=0.012) in the Bellinghausen and Amundsen Seas (BellAm). In contrast, when the recent decline is omitted from the analysis and only data until 2015 are included, the (annual and seasonal) increases of the SIE in whole Antarctica and the Ross Sea become significant, while the significance of the decreasing trends in BellAm is slightly decreased. We consider this as a first indication that the Antarctic SIE may have reached a turning point towards a further decrease.

Beschreibung: Study region: The Upper Niger and Bani River basins in West Africa. Study focus: The growing demand for food, water, and energy led Mali and Guinea to develop ambitious hydropower and irrigation plans, including the construction of a new dam and the extension of irrigation schemes. These two developments will take place upstream of sensible ecosystem hotspots while the feasibility of development plans in terms of water availability and sustainability is questionable. Where agricultural development in past decades focused mainly on intensifying dry-season crops cultivation, future plans include extension in both the dry and wet seasons. New hydrological insights for the region: Today’s irrigation demand corresponds to 7% of the average annual Niger discharge and could account to one third in 2045. An extension of irrigated agriculture is possible in the wet season, while extending dry-season cropping would be largely compromised with the one major existing Sélingué dam. An additional large Fomi or Moussako dam would not completely satisfy dry-season irrigation demands in the 2045 scenario but would reduce the estimated supply gap from 36% to 14%. However, discharge peaks may decrease by 40% reducing the inundated area in the Inner Niger Delta by 21%, while average annual discharge decreases by 30%. Sustainable development should therefore consider investments in water-saving irrigation and management practices to enhance the feasibility of the envisaged irrigation plans instead of completely relying on the construction of a flow regime altering dam.

Beschreibung: Biological responses to climate change have been widely documented across taxa and regions, but it remains unclear whether species are maintaining a good match between phenotype and environment, i.e. whether observed trait changes are adaptive. Here we reviewed 10,090 abstracts and extracted data from 71 studies reported in 58 relevant publications, to assess quantitatively whether phenotypic trait changes associated with climate change are adaptive in animals. A meta-analysis focussing on birds, the taxon best represented in our dataset, suggests that global warming has not systematically affected morphological traits, but has advanced phenological traits. We demonstrate that these advances are adaptive for some species, but imperfect as evidenced by the observed consistent selection for earlier timing. Application of a theoretical model indicates that the evolutionary load imposed by incomplete adaptive responses to ongoing climate change may already be threatening the persistence of species.

Beschreibung: There is wide agreement that a nexus or integrated approach to managing and governing natural resources such as land, water, and energy can improve environmental, climate, human, and political security. However, few if any countries in the MENA region have made progress in implementing such an approach. There appear to be several constraints inhibiting the development and adoption of nexus approaches. These constraints include strong sectoral silos, insufficient incentives for integrated planning and policy making at all levels, and limited vision, knowledge, and practical experience to guide successful implementation. In turn, the limited implementation and hence lack of empirical evidence of a nexus approach, which could demonstrate its benefits, does little to strengthen political will for the development of adequate incentives, structures, and procedures. Against this backdrop, this paper presents five case studies which take an integrated approach, in three MENA countries, namely Jordan, Lebanon, and Morocco. Based on an analytical framework developed here, the paper analyses and compares the success factors for nexus implementation, and also for transfer and upscaling. The analysis emphasizes the need for appropriate framework conditions, targeted investments and pioneering actors, to make integrated approaches across sectors and levels work. With the evidence presented, the paper aims to set in motion a positive or virtuous cycle of generating more nexus evidence, improved framework conditions, further nexus implementation on the ground, and from that even more nexus evidence. Finally, the paper contributes to overcoming the repeated requests for better definition and conceptualization of the nexus, which often has slowed down adoption of the concept.

Beschreibung: The nonlinear dynamics of a combustion system in a modern common-rail dual-fuel engine has been studied. Using nonlinear dynamic data analysis (phase space reconstruction, recurrence plots, recurrence qualification analysis and wavelet analysis), the effect of ethanol fumigation on the dynamic behaviour of a combustion system has been examined at an engine speed of 2000 rpm with engine load rates of 50%, 75% and 100% and ethanol substitutions up to 40% (by energy) in 10% increments for each engine load. The results show that the introduction of ethanol has a significant effect on inter-cycle combustion variation (ICV) and the dynamics of the combustion system for all of the studied engine loads. For pure diesel mode and lower ethanol substitutions, the ICV mainly exhibits multiscale dynamics: strongly periodic and/or intermittent fluctuations. As the ethanol substitution is increased, the combustion process gradually transfers to more persistent low-frequency variations. At different engine loads, we can observe the bands with the strongest spectral power density that persist over the entire 4000 engine cycles. Compared to high engine loads (75% and 100%), the dynamics of the combustion system at a medium engine load (50%) was more sensitive to the introduction of ethanol. At higher ethanol substitutions, the increased ICV and the complexity of the combustion system at the medium load are attributable to the enhanced cooling caused by the excessive ethanol evaporation, while the low-frequency large-scale combustion fluctuations for the higher engine loads are likely caused by cyclic excitation oscillation during the transition of the combustion mode.

Beschreibung: This paper examines observed changes in the indices of mean precipitation in Poland, based on daily precipitation records for 45 stations in Poland from 1961 to 2017. Changes in annual, semi-annual, seasonal, as well as monthly precipitation totals are examined. In addition, changes in the number of days with precipitation (≥ 1 mm), as well as in the Simple Daily Intensity Index and the ratio of precipitation in the warm half-year to precipitation in the cold half-year are studied. Many changes are detected, but most of them are not statistically significant at the 0.1 level. Yet, there are regionally consistent seasonal changes, with a dominating clear precipitation increase in spring and winter. The Student’s t-test for the comparison of means for two intervals: 1961–1990 and 1991–2017 revealed statistically significant increases for annual and spring precipitation, as well as for Simple Daily Intensity Index, and monthly data: increases for February, March, July, September, October and decreases for: June, August, November, December.

Beschreibung: Introduction: Chronic undernutrition affects over 150 million children worldwide and has serious consequences. The causes are complex and include insufficient dietary diversity and poor hygiene practices. Systematic reviews of nutrition-sensitive agricultural interventions concluded that while these hold promise, there is insufficient evidence for their impact on child growth. The Food and Agricultural Approaches to Reducing Malnutrition (FAARM) project is a 1:1 cluster-randomised trial aiming to evaluate the impact of a Homestead Food Production (HFP) programme implemented by Helen Keller International on women’s and children’s undernutrition. Methods and analysis: The HFP intervention comprises training of women’s groups and asset distribution to support year-round home gardening, poultry rearing and improved nutrition and hygiene practices. Formal trainings are supplemented by behaviour change communication during household visits, and facilitated links between producer groups and market actors. The FAARM trial will examine if and how this complex intervention reduces undernutrition. In 2015, FAARM enrolled married women and their children (0–3 years) in 96 rural settlements of Habiganj district in Sylhet division, Bangladesh. Covariate-constrained randomisation was used to assign 48 settlements to receive a 3-year HFP intervention, with the other 48 acting as controls, targeting over 2700 women. To study impact pathways, a surveillance system collects data on all participants every 2 months. In late 2019, children 0–3 years of age (born during the intervention period) will be surveyed, thus capturing impact during the critical first 1000 days of life. Children’s length/height-for-age z-scores will be compared between intervention and control arms using mixed-effects linear regression. Secondary outcomes include women’s and children’s micronutrient status, dietary intake, dietary diversity and other indicators of child growth, development and morbidity. Ethics and dissemination: Ethical approval was received in Bangladesh and Germany. Results will be disseminated through peer-reviewed publications and presentations in Bangladesh and internationally. Trial registration number: NCT02505711; Pre-results.

Beschreibung: On the emergence of large clusters of acoustic power sources at the onset of thermoacoustic instability in a turbulent combustor

Beschreibung: Prediction of traffic congestion is one of the core issues in the realization of smart traffic. Accurate prediction depends on understanding of interactions and correlations between different city locations. While many methods merely consider the spatio-temporal correlation between two locations, here we propose a new approach of capturing the correlation network in a city based on realtime traffic data. We use the weighted degree and the impact distance as the two major measures to identify the most influential locations. A road segment with larger weighted degree or larger impact distance suggests that its traffic flow can strongly influence neighboring road sections driven by the congestion propagation. Using these indices, we find that the statistical properties of the identified correlation network is stable in different time periods during a day, including morning rush hours, evening rush hours, and the afternoon normal time respectively. Our work provides a new framework for assessing interactions between different local traffic flows. The captured correlation network between different locations might facilitate future studies on predicting and controlling the traffic flows.

Beschreibung: In subsistence farming populations of sub-Saharan Africa reliant on rainfed agriculture, years of low crop yields result in poorer child nutrition and survival. Estimates of such impacts are critical for their reduction and prevention. We developed a model to quantify such health impacts, and the degree to which they are attributable to weather variations, for a subsistence farming population in the Nouna district of Burkina Faso (89,000 people in 2010). The method combines data from a new weather-crop yield model with empirical epidemiological risk functions. We quantify the child mortality impacts for 1984–2012 using observed weather data and estimate potential future burdens in 2050 and 2100 using daily weather data generated by global climate models parameterized to simulate global warming of 1.5 °C above pre-industrial levels. For 1984–2012, crop yields below 90% of the period average were estimated to result in the total of 109.8 deaths per 10,000 children 〈5 years, or around 7122.0 years of life lost, 72% of which are attributable to unfavourable weather conditions in the crop growing season. If all non-weather factors are assumed to remain unchanged, the mortality burden related to low crop yields would increase about twofold under 1.5 °C global warming by 2100. These results emphasize the importance and value of developing strategies to protect against the effects of low crop yields and specifically the adverse impact of unfavourable weather conditions in such settings under the current and future climate.

Beschreibung: Anthropogenic climate change is affecting agriculture and crop production. The responses of horticultural and agricultural systems to changing climatic conditions can be non-linear and at times counter-intuitive. Depending on the characteristics of the system, the actual impact can arise as a result of a combination of climate hazards or compound events. Here, we show that compound events can lead to increased risk of frost damage for apple fruit trees in Germany in a 2 °C warmer world of up to 10% relative to present day. Although the absolute number of frost days is declining, warmer winters also lead to earlier blossom of fruit trees, which in turn can lead to regionally dependent increased risks of the occurrence of frost days after apple blossom. In southern Germany, warmer winters may also lead to an increase in years in which apple yield is negatively affected by a lack of sufficient amount of cold days to trigger the seasonal response of the trees. Our results show how cropping system responses to seasonal climate can lead to unexpected effects of increased risk of frost damage as a result of warmer winters. An improved understanding of ecosystem responses to changes in climate signals is important to fully assess the impacts of climate change.

Beschreibung: A complex spatiotemporal pattern with coexisting coherent and incoherent domains in a network of identically coupled oscillators is known as a chimera state. Here, we report the emergence and existence of a novel type of nonstationary chimera pattern in a network of identically coupled Hindmarsh–Rose neuronal oscillators in the presence of synaptic couplings. The development of brain function is mainly dependent on the interneuronal communications via bidirectional electrical gap junctions and unidirectional chemical synapses. In our study, we first consider a network of nonlocally coupled neurons where the interactions occur through chemical synapses. We uncover a new type of spatiotemporal pattern, which we call “spike chimera” induced by the desynchronized spikes of the coupled neurons with the coherent quiescent state. Thereafter, imperfect traveling chimera states emerge in a neuronal hypernetwork (which is characterized by the simultaneous presence of electrical and chemical synapses). Using suitable characterizations, such as local order parameter, strength of incoherence, and velocity profile, the existence of several dynamical states together with chimera states is identified in a wide range of parameter space. We also investigate the robustness of these nonstationary chimera states together with incoherent, coherent, and resting states with respect to initial conditions by using the basin stability measurement. Finally, we extend our study for the effect of firing regularity in the observed states. Interestingly, we find that the coherent motion of the neuronal network promotes the entire system to regular firing. Several cognitive neuronal processes strictly depend on interneuronal communications that take place mainly through two types of synapses: the electrical communication via gap junctional and the chemical synaptic interaction. Neuronal synchrony plays a fundamental role in the normal operation of various neuronal processes. In particular, this property is closely related to the neuronal plasticity, information exchange, etc. Chimera state is a self-organized complex spatiotemporal pattern that deals with the simultaneous appearance of synchrony and desynchrony behaviors in the neuronal networks. The emergence of the chimera states in the neuronal network was investigated previously by considering the electrical and the chemical synaptic coupling or the interaction through another medium. In all previous studies on chimera states, only bidirectional chemical synaptic interactions were considered. However, in the real situation, chemical communication happens unidirectionally between two neurons, whereas electrical communication happens bidirectionally between two adjacent neurons. In this context, here, we study the existence and emergence of chimera patterns in a neuronal hypernetwork by taking a unidirectional chemical synapse and bidirectional electrical coupling. In our study, each neuron in the network is modeled with a Hindmarsh–Rose neuronal oscillator. Through the interplay of the network topology and the chemical synaptic coupling function, a novel type of nonstationary chimera pattern, called “spike chimera,” is found, which is characterized by uncorrelated spikes and a coherent quiescent state of the coupled neurons. These complex spatiotemporal patterns are robust with respect to initial conditions. We investigate the firing regularities of the coupled neurons in different dynamical states. With the help of various measurements, the different collective dynamical features, such as incoherent, coherent, steady state dynamics, and spike chimera states, are characterized and quantified in the parameter space.

Beschreibung: Facility delivery should reduce early neonatal mortality. We used the Slope Index of Inequality and logistic regression to quantify absolute and relative socioeconomic inequalities in early neonatal mortality (0 to 6 days) and facility delivery among 679,818 live births from 72 countries with Demographic and Health Surveys. The inequalities in early neonatal mortality were compared with inequalities in postneonatal infant mortality (28 days to 1 year), which is not related to childbirth. Newborns of the richest mothers had a small survival advantage over the poorest in unadjusted analyses (−2.9 deaths/1,000; OR 0.86) and the most educated had a small survival advantage over the least educated (−3.9 deaths/1,000; OR 0.77), while inequalities in postneonatal infant mortality were more than double that in absolute terms. The proportion of births in health facilities was an absolute 43% higher among the richest and 37% higher among the most educated compared to the poorest and least educated mothers. A higher proportion of facility delivery in the sampling cluster (e.g. village) was only associated with a small decrease in early neonatal mortality. In conclusion, while socioeconomically advantaged mothers had much higher use of a health facility at birth, this did not appear to convey a comparable survival advantage.

Beschreibung: Increasing human demands for water, energy, food and materials, are expected to accentuate resource supply challenges over the coming decades. Experience suggests that long-term strategies for a single sector could yield both trade-offs and synergies for other sectors. Thus, long-term transition pathways for linked resource systems should be informed using nexus approaches. Global integrated assessment models can represent the synergies and trade-offs inherent in the exploitation of water, energy and land (WEL) resources, including the impacts of international trade and climate policies. In this study, we review the current state-of-the-science in global integrated assessment modeling with an emphasis on how models have incorporated integrated WEL solutions. A large-scale assessment of the relevant literature was performed using online databases and structured keyword search queries. The results point to the following main opportunities for future research and model development: (1) improving the temporal and spatial resolution of economic models for the energy and water sectors; (2) balancing energy and land requirements across sectors; (3) integrated representation of the role of distribution infrastructure in alleviating resource challenges; (4) modeling of solution impacts on downstream environmental quality; (5) improved representation of the implementation challenges stemming from regional financial and institutional capacity; (6) enabling dynamic multi-sectoral vulnerability and adaptation needs assessment; and (7) the development of fully-coupled assessment frameworks based on consistent, scalable, and regionally-transferable platforms. Improved database management and computational power are needed to address many of these modeling challenges at a global-scale. View Full-Text

Beschreibung: Stroke and traumatic brain injury are often associated with formation of brain edema, which is a potentially fatal pathological state provoking extensive accumulation of fluid in the brain tissues resulting in elevation of intracranial pressure and leading to impaired nerve function. There is only symptomatic anti-edema therapy is currently available. Therefore, the development of novel strategies to remove edema fluid is required. The brain edema is classified as vasogenic or cytotoxic edema, which associated with excess accumulation of fluid (edema) around capillaries resulting from disruption of the blood-brain barrier (BBB) or intracellular spaces (cell swelling) of the brain, respectively. In this brief review, we discuss possible mechanisms underlying brain edema formation and new strategies in development of novel of anti-edema drugs.

Beschreibung: The response of land ecosystems to future climate change is among the largest unknowns in the global climate-carbon cycle feedback. This uncertainty originates from how dynamic global vegetation models (DGVMs) simulate climate impacts on changes in vegetation distribution, productivity, biomass allocation, and carbon turnover. The present-day availability of a multitude of satellite observations can potentially help to constrain DGVM simulations within model-data integration frameworks. Here, we use satellite-derived datasets of the fraction of absorbed photosynthetic active radiation (FAPAR), sun-induced fluorescence (SIF), above-ground biomass of trees (AGB), land cover, and burned area to constrain parameters for phenology, productivity, and vegetation dynamics in the LPJmL4 DGVM. Both the prior and the optimized model accurately reproduce present-day estimates of the land carbon cycle and of temporal dynamics in FAPAR, SIF and gross primary production. However, the optimized model reproduces better the observed spatial patterns of biomass, tree cover, and regional forest carbon turnover. Using a machine learning approach, we found that remaining errors in simulated forest carbon turnover can be explained with bioclimatic variables. This demonstrates the need to improve model formulations for climate effects on vegetation turnover and mortality despite the apparent successful constraint of simulated vegetation dynamics with multiple satellite observations.

Beschreibung: The coupled behavior of the acoustic pressure and the heat release rate fluctuations is studied in a swirl-stabilized combustor during the transition of system dynamics from combustion noise to thermoacoustic instability via intermittency. The framework of synchronization is used to analyze the temporal as well as the spatiotemporal behavior of these oscillations. The results of the synchronization transition observed in this combustor are further compared and contrasted with those recently reported by Pawar et al. (“Thermoacoustic Instability as Mutual Synchronization Between the Acoustic Field of the Confinement and Turbulent Reactive Flow,” Journal of Fluid Mechanics, Vol. 827, Sept. 2017, pp. 664–693) and Mondal et al. (“Onset of Thermoacoustic Instability in Turbulent Combustors: An Emergence of Synchronized Periodicity Through Formation of Chimera-like States,” Journal of Fluid Mechanics, Vol. 811, Jan. 2017, pp. 659–681) in a bluff-body stabilized combustor. A rigorous analysis of the synchronization transition of these oscillations in the frequency domain is also presented. The temporal analysis reveals that the synchronization states and the synchronization transition to thermoacoustic instability of the coupled acoustic pressure and heat release rate fluctuations are similar for both swirl-stabilized and bluff-body stabilized combustors. On the other hand, the spatiotemporal analysis of both the combustors during the state of strongly correlated periodic oscillations shows that, despite the acoustic power production being higher during this state, an increased amount of spatial incoherence is visible in the instantaneous and phase-conditioned phasor field of the reaction zone of the swirl-stabilized combustor as compared to that of the bluff-body stabilized combustor. In short, the present study unifies the synchronization transition of coupled oscillations in these turbulent combustors, wherein the mechanisms behind the onset of thermoacoustic instabilities are apparently different.