ALBERT

Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Derr, N. J., Fronk, D. C., Weber, C. A., Mahadevan, A., Rycroft, C. H., & Mahadevan, L. Flow-driven branching in a frangible porous medium. Physical Review Letters, 125(15), (2020): 158002, doi:10.1103/PhysRevLett.125.158002.

Description: Channel formation and branching is widely seen in physical systems where movement of fluid through a porous structure causes the spatiotemporal evolution of the medium. We provide a simple theoretical framework that embodies this feedback mechanism in a multiphase model for flow through a frangible porous medium with a dynamic permeability. Numerical simulations of the model show the emergence of branched networks whose topology is determined by the geometry of external flow forcing. This allows us to delineate the conditions under which splitting and/or coalescing branched network formation is favored, with potential implications for both understanding and controlling branching in soft frangible media.

Description: N. D. was partially supported by the NSF-Simons Center for Mathematical and Statistical Analysis of Biology at Harvard, Grant No. 1764269, and the Harvard Quantitative Biology Initiative. C. H. R. and N. D. were partially supported by the National Science Foundation under Grant No. DMS-1753203. C. H. R. was partially supported by the Applied Mathematics Program of the U.S. DOE Office of Science Advanced Scientific Computing Research under Contract No. DE-AC02-05CH11231. L. M. was partially supported by the National Science Foundation under Grants No. DMR-2011754 and No. DMR-1922321.

Description: Earth's climate can be understood as a dynamical system that changes due to external forcing and internal couplings. Essential climate variables, such as surface air temperature, describe this dynamics. Our current interglacial, the Holocene (11 700 yr ago to today), has been characterized by small variations in global mean temperature prior to anthropogenic warming. However, the mechanisms and spatiotemporal patterns of fluctuations around this mean, called temperature variability, are poorly understood despite their socioeconomic relevance for climate change mitigation and adaptation. Here we examine discrepancies between temperature variability from model simulations and paleoclimate reconstructions by categorizing the scaling behavior of local and global surface air temperature on the timescale of years to centuries. To this end, we contrast power spectral densities (PSD) and their power-law scaling using simulated and observation-based temperature series of the last 6000 yr. We further introduce the spectral gain to disentangle the externally forced and internally generated variability as a function of timescale. It is based on our estimate of the joint PSD of radiative forcing, which exhibits a scale break around the period of 7 yr. We find that local temperature series from paleoclimate reconstructions show a different scaling behavior than simulated ones, with a tendency towards stronger persistence (i.e., correlation between successive values within a time series) on periods of 10 to 200 yr. Conversely, the PSD and spectral gain of global mean temperature are consistent across data sets. Our results point to the limitation of climate models to fully represent local temperature statistics over decades to centuries. By highlighting the key characteristics of temperature variability, we pave a way to better constrain possible changes in temperature variability with global warming and assess future climate risks.

Description: 〈p〉The invasion of Ukraine by Russian forces has led to sharp rises in gas prices in Europe and around the world with real concerns about the possible curtailment of gas flows from Russia to Europe. Pipeline imports from Russia began falling in the last quarter of 2021 and declined even further in January and most […]〈/p〉 〈p〉The post 〈a rel="nofollow" href="https://www.oxfordenergy.org/publications/ukraine-invasion-what-this-means-for-the-european-gas-markets/"〉Ukraine Invasion: What This Means for the European Gas Market〈/a〉 appeared first on 〈a rel="nofollow" href="https://www.oxfordenergy.org/"〉Oxford Institute for Energy Studies〈/a〉.〈/p〉

Description: 〈p〉In late 2021, China experienced a severe electricity supply crisis that affected 20 provinces. Industrial activity was curtailed, and even households suffered prolonged outages in some areas. The country is no stranger to periodic energy supply shortages and in many outages in the past, the principal causes involved either poor policy coordination or a clash […]〈/p〉 〈p〉The post 〈a rel="nofollow" href="https://www.oxfordenergy.org/publications/oxford-energy-forum-the-2021-energy-crisis-implications-for-chinas-energy-market-and-policies/"〉Oxford Energy Forum – The 2021 energy crisis: Implications for China’s energy market and policies – Issue 131〈/a〉 appeared first on 〈a rel="nofollow" href="https://www.oxfordenergy.org/"〉Oxford Institute for Energy Studies〈/a〉.〈/p〉

Description: 〈p〉Following Russia’s invasion of Ukraine on 24 February 2022, energy markets are in turmoil. Oil and gas prices are rising and exhibiting high volatility as the markets grapple with the impact of sanctions and the prospect of reduced flows from Russia . China is heavily exposed to Russian commodity exports and to global markets. The […]〈/p〉 〈p〉The post 〈a rel="nofollow" href="https://www.oxfordenergy.org/publications/the-russian-invasion-of-ukraine-and-chinas-energy-markets/"〉The Russian invasion of Ukraine and China’s energy markets〈/a〉 appeared first on 〈a rel="nofollow" href="https://www.oxfordenergy.org/"〉Oxford Institute for Energy Studies〈/a〉.〈/p〉

Description: 〈p〉In this podcast, James Henderson talks to Anouk Honoré about her forthcoming article “Demand-side factors behind the historical gas price rally in Europe in 2021”. This article is part of a trilogy entitled “A Series of Unfortunate Events” that analyses the main supply and demand factors in the European gas market(s) that contributed to rising gas prices since summer […]〈/p〉 〈p〉The post 〈a rel="nofollow" href="https://www.oxfordenergy.org/publications/oxford-energy-podcast-a-series-of-unfortunate-events-demand-side-factors-in-the-european-gas-price-rally-in-2021/"〉Oxford Energy Podcast – A Series of Unfortunate Events:​ Demand-Side Factors in the European Gas Price Rally ​in 2021〈/a〉 appeared first on 〈a rel="nofollow" href="https://www.oxfordenergy.org/"〉Oxford Institute for Energy Studies〈/a〉.〈/p〉 〈div class="enclosure"〉〈p class="enclosure-content"〉〈audio preload="none" src="https://a9w7k6q9.stackpathcdn.com/wpcms/wp-content/uploads/2022/02/Podcast-132-EU-Gas-Demand.mp3" controls="controls"〉〈/audio〉 〈a download="" href="https://a9w7k6q9.stackpathcdn.com/wpcms/wp-content/uploads/2022/02/Podcast-132-EU-Gas-Demand.mp3"〉💾〈/a〉〈/p〉〈/div〉

Description: 〈p〉In this latest OIES podcast James Henderson talks to Mike Fulwood and Jack Sharples about their latest research on the possible impact of an interruption of Russian gas supplies to Europe. After a quick update on current gas prices Jack Sharples reviews the current state of gas supply to Europe, looking at flows in 2021 […]〈/p〉 〈p〉The post 〈a rel="nofollow" href="https://www.oxfordenergy.org/publications/oxford-energy-podcast-the-russian-invasion-of-ukraine-implications-for-the-european-gas-market/"〉Oxford Energy Podcast – The Russian invasion of Ukraine – implications for the European gas market〈/a〉 appeared first on 〈a rel="nofollow" href="https://www.oxfordenergy.org/"〉Oxford Institute for Energy Studies〈/a〉.〈/p〉 〈div class="enclosure"〉〈p class="enclosure-content"〉〈audio preload="none" src="https://a9w7k6q9.stackpathcdn.com/wpcms/wp-content/uploads/2022/03/Podcast-135-The-Russian-invasion-of-Ukraine-–-implications-for-the-European-gas-market.mp3" controls="controls"〉〈/audio〉 〈a download="" href="https://a9w7k6q9.stackpathcdn.com/wpcms/wp-content/uploads/2022/03/Podcast-135-The-Russian-invasion-of-Ukraine-–-implications-for-the-European-gas-market.mp3"〉💾〈/a〉〈/p〉〈/div〉

Description: 〈p〉This month’s OIES Oil Monthly Special Issue assesses the implications of the Ukraine war on our short-term oil market outlook for market balances and prices to 2023. The analysis considers two scenarios. A Reference case in which self-sanctioning measures and obstacles in redirecting Russian crude flows due to financing and shipping constraints results in a […]〈/p〉 〈p〉The post 〈a rel="nofollow" href="https://www.oxfordenergy.org/publications/oies-oil-monthly-issue-12/"〉OIES Oil Monthly – Special Issue 12〈/a〉 appeared first on 〈a rel="nofollow" href="https://www.oxfordenergy.org/"〉Oxford Institute for Energy Studies〈/a〉.〈/p〉

Description: 〈p〉This paper aims to examine consumer behaviour towards, and the willingness to adopt, ‘green steel’ in the automotive sector. Semi-structured interviews were held with experts from global, regional and country-specific industry associations and automakers. This paper appraises potential demand for green steel within different vehicle types (based both on size and powertrain) and shows that manufacturers […]〈/p〉 〈p〉The post 〈a rel="nofollow" href="https://www.oxfordenergy.org/publications/steeling-the-race-green-steel-as-the-new-clean-material-in-the-automotive-sector/"〉Steeling the race: ‘Green steel’ as the new clean material in the automotive sector〈/a〉 appeared first on 〈a rel="nofollow" href="https://www.oxfordenergy.org/"〉Oxford Institute for Energy Studies〈/a〉.〈/p〉

Description: 〈p〉In this podcast David Ledesma discusses the implications of Russia’s invasion of Ukraine for global oil markets with Bassam Fattouh, Director of OIES based on his latest paper: Russia-Ukraine crisis: Implications for global oil markets with Andreas Economou and Ahmed Mehdi. In this wide-ranging discussion, Bassam Fattouh discusses what the potential loss of Russian oil […]〈/p〉 〈p〉The post 〈a rel="nofollow" href="https://www.oxfordenergy.org/publications/oxford-energy-podcast-russia-ukraine-crisis-implications-for-global-oil-markets/"〉Oxford Energy Podcast – Russia-Ukraine crisis – Implications for global oil markets〈/a〉 appeared first on 〈a rel="nofollow" href="https://www.oxfordenergy.org/"〉Oxford Institute for Energy Studies〈/a〉.〈/p〉 〈div class="enclosure"〉〈p class="enclosure-content"〉〈audio preload="none" src="https://a9w7k6q9.stackpathcdn.com/wpcms/wp-content/uploads/2022/03/Podcast-134-Russia-Ukraine-crisis-Implications-for-global-oil-markets.mp3" controls="controls"〉〈/audio〉 〈a download="" href="https://a9w7k6q9.stackpathcdn.com/wpcms/wp-content/uploads/2022/03/Podcast-134-Russia-Ukraine-crisis-Implications-for-global-oil-markets.mp3"〉💾〈/a〉〈/p〉〈/div〉