Report The Panel agreed on the outline of the 2027 IPCC Methodology Report on Carbon Dioxide Removal Technologies, Carbon Capture, Utilization, and Storage for National Greenhouse Gas Inventories (Additional guidance) at its 63rd Session held in Lima, Peru from 27-30 October 2025 (Decision IPCC-LXIII-6). The report will be a single Methodology Report comprising an Overview Chapter and six volumes consistent with the format of the 2006 IPCC Guidelines for National Greenhouse Gas Inventories. The structure of the Methodology Report is consistent with the 2006 IPCC Guidelines so as to make it easier for inventory compilers to use this Methodology Report with the 2006 IPCC Guidelines. Topics that will be addressed include: Transport, injection and sequestering of CO2 in relation to enhanced oil, gas, and coal-bed methane recovery Production of products containing or derived from captured and/or removed CO2 Carbonation of cement and lime-based structures Soil carbon sinks and related emissions enhanced through biochar and weathering and other elements Coastal wetlands carbon dioxide removal types not in previous IPCC Guidelines as well as additional information on mangroves, tidal marshes and seagrass in coastal waters Durable biomass products Carbon dioxide capture from combustion and process gases Direct air capture Carbon dioxide utilisation Carbon dioxide transport including cross border issues Carbon dioxide injection and storage CO2 removal through direct capture of CO2 from water already processed by inland and coastal facilities; and related elements across the range of categories of the IPCC Guidelines. The national greenhouse gas inventory includes sources and sinks occurring within the territory over which a country has jurisdiction. Over 150 experts are expected to participate in the writing process, which will be completed by 2027. The participants will be selected by the Task Force Bureau taking into account scientific and technical expertise, geographical and gender balance to the extent possible in line with Appendix A to the Principles Governing IPCC Work. The First Lead Authors’ meeting will be held in Rome, Italy, in April 2026. Preparatory Work The decision by the Panel to prepare this Methodology Report was informed by the work of experts at the scoping meeting held in Copenhagen, Denmark, from 14-16 October 2024. Prior to the scoping meeting, an expert meeting was held at Vienna, Austria 1-3 July 2024. These meetings considered Carbon Dioxide Removal (CDR) methods mentioned in the AR6 WGIII Report as a starting point for discussion and noted that several CDR activities have been already covered by the existing IPCC Guidelines. More Information The IPCC Secretary has written to national government focal points inviting nominations of authors by 12 December 2025.

Fast Facts Medicaid programs that cover prescription drugs are generally required to cover drugs that are (1) FDA approved and (2) made by a manufacturer that participates in the Medicaid Drug Rebate Program. 13 Medicaid programs didn’t cover Mifeprex and its generic equivalent, Mifepristone Tablets, 200 mg, when required. These drugs are used for medical abortion. We recommended the Centers for Medicare & Medicaid Services ensure Medicaid programs comply with federal requirements for covering Mifepristone Tablets, 200 mg. We also reiterated our 2019 recommendation on Mifeprex, which hasn’t been implemented. White pills spilling from a pill bottle. Skip to Highlights Highlights What GAO Found Medicaid programs that choose to cover outpatient prescription drugs are required to cover all Food and Drug Administration (FDA) approved drugs for their medically accepted indications when those drugs are made by a manufacturer that participates in the Medicaid Drug Rebate Program (MDRP), except as outlined in federal law. The FDA has approved two drugs—Mifeprex in 2000 and its generic equivalent in 2019, referred to as Mifepristone Tablets, 200 mg—for the medical termination of an intrauterine pregnancy, known as a medical abortion. Danco Laboratories and GenBioPro are the exclusive manufacturers of Mifeprex and Mifepristone Tablets, 200 mg, respectively, and both manufacturers participate in the MDRP. Medicaid programs in all 50 states, the District of Columbia, and Puerto Rico cover prescription drugs and participate in the MDRP. According to officials from the Centers for Medicare & Medicaid Services (CMS)—the federal agency within the Department of Health and Human Services (HHS) responsible for ensuring Medicaid programs’ compliance—none of the MDRP’s statutory exceptions apply to Mifeprex or Mifepristone Tablets, 200 mg. Thus, these 52 Medicaid programs must cover these drugs when prescribed for medical abortion in circumstances eligible for federal funding, such as when the pregnancy is the result of rape or incest. GAO identified gaps in Medicaid programs’ coverage of Mifeprex and Mifepristone Tablets, 200 mg. Officials from 35 of the 49 programs who responded to GAO questions said their programs covered Mifeprex and Mifepristone Tablets, 200 mg for medical abortion, as of December 31, 2024. In contrast, officials from 13 programs told GAO their programs did not cover either drug for medical abortion. An official from the remaining program did not specify the medical indications for which its program covered the drugs. Medicaid Programs’ Coverage of Danco Laboratories’ Mifeprex and GenBioPro’s Mifepristone Tablets, 200 mg, as of December 31, 2024 Note: For more details, see fig. 1 in GAO-25-107911. State officials’ responses to GAO’s questions indicated that some states may not be complying with the MDRP requirements for covering Mifeprex and Mifepristone Tablets, 200 mg. However, CMS has not determined the extent to which states comply with the MDRP requirements for these drugs. CMS officials told GAO they were not aware of the following: Nine programs did not cover Mifeprex and Mifepristone Tablets, 200 mg for any medical indication, as of December 31, 2024; GAO reported four of these programs did not cover Mifeprex in 2019. Mifepristone Tablets, 200 mg was not available at the time of GAO’s 2019 report. Four additional Medicaid programs did not cover either drug when prescribed for medical abortion, as of December 31, 2024. CMS was not aware of these coverage gaps, in part, because it had not implemented GAO’s 2019 recommendation to take actions to ensure Medicaid programs comply with MDRP requirements to cover Mifeprex. CMS also has not taken actions related to the coverage of Mifepristone Tablets, 200 mg, as of August 2025. Without such actions, CMS lacks assurance that Medicaid programs comply with MDRP requirements and Medicaid beneficiaries may lack access to these drugs when appropriate. Why GAO Did This Study GAO was asked to describe Medicaid programs’ coverage of mifepristone. This report examines Medicaid programs’ coverage of Mifeprex and Mifepristone Tablets, 200 mg, among other things. GAO reviewed laws and CMS guidance on the MDRP, and coverage of Mifeprex and Mifepristone Tablets, 200 mg. GAO also sent written questions to officials from the 52 Medicaid programs that participate in the MDRP regarding their coverage of these drugs, and reviewed officials’ responses from the 49 programs that provided GAO information. Recommendations GAO reiterates its 2019 recommendation that CMS take actions to ensure states’ compliance with MDRP requirements to cover Mifeprex. GAO also recommends that CMS determine the extent to which states comply with federal Medicaid requirements regarding coverage of GenBioPro’s Mifepristone Tablets, 200 mg, and take actions, as appropriate, to ensure compliance. In response to the recommendation, HHS noted it is reviewing applicable law and will determine the best course of action to address it moving forward. Recommendations for Executive Action Agency Affected Recommendation Status Centers for Medicare & Medicaid Services The Administrator of CMS should determine the extent to which states comply with federal Medicaid requirements regarding coverage of GenBioPro's Mifepristone Tablets, 200 mg, and take actions, as appropriate, to ensure compliance. (Recommendation 1) Open Actions to satisfy the intent of the recommendation have not been taken or are being planned. When we confirm what actions the agency has taken in response to this recommendation, we will provide updated information. Full Report Full Report (11 pages)

05.12.2025 – The European Scientific Advisory Board on Climate Change, established under the European Climate Law, will continue to be supported in its second term (2026-2030) by Ottmar Edenhofer. The Director of the Potsdam Institute for Climate Impact Research (PIK) has now been appointed by the Management Board of the European Environment Agency in Copenhagen for another four-year term on the Advisory Board, beginning on 24 March 2026. Advising EU policymakers on the path to the declared goal of climate neutrality: PIK Director Ottmar Edenhofer. Photo: PIK/Karkow The Advisory Board gives independent advice and produces reports on EU policies, and their coherence with the Climate Law and the EU’s commitments under the Paris Agreement. It consists of 15 high-level scientific experts covering a wide range of relevant fields. Edenhofer is serving as the Advisory Board’s current Chair during its first term (2022-2026). Highlights during this period have included scientific recommendations for an ambitious EU climate target for 2040, an analysis of the action needed to achieve climate neutrality, and a study on scaling up atmospheric carbon removals. “I am very thankful for the great opportunity to continue supporting EU climate policy in this service role for the next four years,” says Edenhofer, who is also Professor for The Economics and Politics of Climate Change at the Technische Universität Berlin. “The European Union has taken some important steps in recent years towards its declared goal of climate neutrality by 2050. It remains important to make climate policy cost-effective, socially balanced and consistent with the requirements of an internationally competitive economy. As a member of the Advisory Board, I will do my best to provide scientific advice to policymakers on this task.” The composition of the Advisory Board for the next four-year term has now been decided through an open, fair and transparent selection process lasting several months. The decision on who will chair the body in future is not expected until beginning of the second term. The other members of the Advisory Board in the second term are: • Annela Anger-Kraavi – University of Cambridge • Constantinos Cartalis – National and Kapodistrian University of Athens • Suraje Dessai – University of Leeds’ School of Earth, Environment, and Sustainability • Laura Díaz Anadón – University of Cambridge • Vera Eory – Scotland’s Rural College • Lena Kitzing - Technical University of Denmark • Kati Kulovesi – University of Eastern Finland • Lars J. Nilsson – Lund University • Åsa Persson – KTH Royal Institute of Technology’s Climate Action Centre • Keywan Riahi – International Institute for Applied Systems Analysis • Jean-François Soussana – French National Research Institute for Agriculture, Food and the Environment • Giorgio Vacchiano – University of Milan • Detlef van Vuuren – PBL Netherlands Environmental Assessment Agency • Zinta Zommers – University of Toronto

In 2025, the Asia Pacific has steadily built momentum for climate action amid a fraught political backdrop of geopolitical conflict, rising energy demand and high inflation. Already subscribed? Sign in To continue reading, subscribe to Eco‑Business. There's something for everyone. We offer a range of subscription plans. Subscribe now → Access our stories and receive our Insights Weekly newsletter with the free EB Member plan. Unlock unlimited access to our content and archive with EB Circle. Publish your content with EB Premium. Most countries in the region maintained low-carbon ambitions despite anti-climate signals from the United States, with renewable energy capacity set to grow almost twofold by the end of the decade. It is this rapid expansion of clean power that is expected to support cross-border electricity trade in Southeast Asia set to gain more traction in the coming year. Over the past twelve months, the inter of technology and climate has also emerged as a key theme. Asia’s artificial intelligence (AI) sector is poised for robust growth in the coming year, driven by hyperscaler investments in data centres. Eco-Business rounds up five trends that could influence sustainability in Asia in 2026, as the region positions itself in a world reeling from a politicised environmental, social and governance (ESG) backlash that continues to stir markets. 1. Renewable energy boom to fuel APG Asia’s clean energy surge is expected to help advance the long-delayed Asean Power Grid (APG), a project that has remained largely unrealised for nearly three decades but aims to enable cross-border electricity trade within the bloc. The APG regained traction this year when Southeast Asian leaders vowed to make it a top priority to boost interoperability between member states’ electricity grids. Solar power will lead APG’s capacity additions, with 24 gigawatts (GW) potential in Indonesia’s Riau islands and Malaysia’s Sarawak. The Philippines aims to utilise offshore wind to contribute to the regional grid, aiming to tap 50 GW of the resource by 2050. Elsewhere in Asia, new capacity additions are projected to expand by 670 GW from 2025 to 2030, with solar photovoltaic sources from India accounting for nearly three-quarters of the total. But renewable energy sources alone will not be able to support a regional grid, warned Kitty Bu, vice president for Southeast Asia at Global Energy Alliance for People and Planet (GEAPP). Southeast Asia still relies heavily on fossil fuels for up to 80 per cent of its primary energy supply, with coal and natural gas dominating electricity generation. For large-scale regeneration to support the APG, battery storage is a critical technology, Bu told Eco-Business. A battery energy storage system (BESS) in a 500-megawatt (MW) solar farm in Maharashtra, India. Image: Global Energy Alliance But the deployment of battery energy storage systems (BESS) in Asia faces key barriers such as high costs and technical gaps. Bu said GEAPP is working with the Asian Development Bank (ADB) to pool philanthropic and development finance to de-risk BESS projects. They are also providing technical assistance, which includes grid integration studies, procurement guidelines and AI-optimised business models for scalable pilots. “Without battery storage, the intermittent nature of the renewables will become a constraint, rather than an enabler in this Asean power grid,” she said. “This growth only translates into grid reliability. If we solve the storage challenge, then we solve the grid challenge.” 2. De-risking facility could boost geothermal Geothermal energy is expected to be another major resource in ramping up the regional grid, said Smile Yu, lawyer for resources, energy and mobility for Japan and Southeast Asia at environmental law nonprofit ClientEarth. The trend is especially visible in Indonesia and the Philippines, which hold some of the world’s largest reserves and can offer steady, renewable power into a regional grid, she told Eco-Business. Indonesia boasts of the world’s largest resource potential at 24 to 29 GW, while the US and Philippines have 30 to 39 GW and 4 GW, respectively, though much remains untapped. A 112.5 MW geothermal plant in Negros Oriental, Philippines, managed by Energy Development Corporation. Image: EDC The Philippines could address its untapped potential through the US$170 million geothermal de-risking facility launched in December, which seeks to accelerate early-stage geothermal exploration. Through the Philippine Geothermal Resource De-Risking Facility (PGRDF), companies can tap into the fund, with the government bearing at least half of the cost for geothermal exploration or drilling through a conditionally repayable grant. The facility was funded through a sovereign loan to the Philippine government from the ADB. “There is growing interest in how improvements in drilling techniques could make geothermal development more efficient and potentially expand the types of sites that can be explored,” said Yu. “Although geothermal is seen as a mature technology, the advancement of new drilling technologies are prompting renewed discussion about geothermal’s long-term role not just in the region but globally as well.” 3. Stricter measures to curb impacts of data centre boom As artificial intelligence (AI) adoption grows, so will the pressure to curb its environmental impact, said Andrew Young, founder and managing director of Singapore-based Envirosolutions and Consulting. “Although power and water are significant hurdles to the growth of hyperscalers, these can be overcome. With the right [regulatory] encouragement, a cleaner, more sustainable industry might arise,” he told Eco-Business. Malaysia started introducing strict water use regulations this year, driven by water shortages related to new data centre demand. The country’s regulators have increasingly conditioned approvals on sustainable design and resource use, with some projects in Johor reportedly rejected when operators failed to show credible plans to reduce power and water footprints. Malaysia has been leading the region’s data centre boom as tech giants like Microsoft and Google have invested about US$2 billion each in it, including a US$236 million deal awarded to local construction firm Gamuda for further expansion. Together with Vietnam, Malaysia has also introduced data‑sovereignty and localisation rules that drive domestic build‑out, prompting authorities to stress that new facilities must meet modern energy‑efficiency and resilience standards. Thailand’s regulators have also started to combine cyber and data rules with infrastructure expectations, signalling that future data-centre growth must align with power‑system stability and national climate targets, even as detailed green metrics are still evolving. Singapore was the first to put a moratorium on data centre development in 2019, primarily due to its demand for power and water outstripping what could be sustainably supplied at the time. Southeast Asia is emerging as a hotspot where large AI players are investing about US$2.3 billion in cloud services and data centres. In the wider region, hyperscaler investment has been projected to rise sharply in 2026, reaching US$552 billion, according to research by Goldman Sachs. Tech giants have been fueling AI infrastructure growth in Asia, positioning the region for major expansion in the coming year. Google is investing US$15 billion in a data hub in India, while Taiwan’s Foxconn is expected to spend up to US$1.37 billion to procure equipment for an AI compute cluster and a supercomputing centre. 4. West–China rivalry intensifies over global critical minerals At a meeting in the Canadian city of Toronto in October, the Group of Seven’s (G7) energy ministers agreed to establish a critical minerals production alliance, countering China’s overwhelming global share of minerals like nickel, a key mineral used for electric vehicle battery manufacturing. G7, which consists of Canada, France, Germany, Italy, Japan, the United Kingdom and the United States, agreed to channel up to US$6.4 billion of critical minerals projects, including 26 new investments, partnerships and research initiatives. G7 leaders have been focused on improving the traceability of minerals and stabilising these supply chains, primarily following Russia’s war with Ukraine and China’s efforts to impose export controls on minerals and rare earth elements. Canada’s energy minister Tim Hodgson has reportedly said that the alliance is intended to “secure transparent, democratic, and sustainable supply chains” by drawing in private capital from across the group. The China Pavilion at COP30. The global clean-energy transition hinges on critical minerals, yet opaque reporting, weak community engagement and uneven ESG compliance remain persistent risks for Chinese-led overseas mining projects. Image: UNclimatechange, CC BY-SA 3.0, via Flickr Tae‑Yoon Kim, acting head of the critical minerals division of the International Energy Agency, described the gathering as a “major opportunity … to start shifting market power,” underscoring worries that China’s state‑directed system can manipulate prices, build strategic stockpiles and influence global material flows. However, Abigail Hunter, executive director of Washington-based research institute Center for Critical Minerals Strategy, warned in a rare earths platform that true progress requires traceability and transparency to “box out” opaque Chinese entities. The platform noted: “Whether the G7 can align around strict traceability rules remains uncertain. Without them, any alliance may look more symbolic than structural. The market’s imbalance rooted in decades of Chinese industrial planning won’t be reversed by declarations alone.” 5. Uneven progress in ESG reporting timelines Southeast Asia’s ESG reporting landscape highlights stark differences in commitment and enforcement as the region enters the new year. This comes amid a global pushback against sustainability reporting requirements. Earlier this year, the European Union moved to ease its Corporate Sustainability Reporting Directive (CSRD) requirements and later, its deforestation-free regulations (EUDR). Singapore, a regional sustainability leader, said it would delay International Sustainability Standards Board (ISSB)-aligned climate reporting requirements for smaller listed firms by up to five years. Singapore’s revised rules now put the city-state, which was among the first in Asia to propose mandatory ISSB-aligned reporting for companies in 2023, behind Malaysia in mandatory sustainability reporting requirements. Listed and large non-listed firms in the neighbouring Southeast Asian nation are expected to start ISSB-aligned reporting, including on Scope 3 emissions, by 2027. It has vowed aggressive action against non-compliant firms under its updated Bursa Malaysia rules, enforcing phased reporting from 2024 to 2026 with penalties for laggards. The Philippines also announced early this year that it will begin implementing mandatory sustainability reporting by 2026, as it aligns itself with the ISSB regulations under a “transitional or phased approach” to mandate sustainability reporting from companies, allowing them to smoothly adjust to new reporting requirements. Related to this story Topics Carbon & Climate Corporate Responsibility Energy Policy & Finance Water Regions Global Southeast Asia Tags ASEAN batteries clean energy data centres emissions energy efficiency ESG fossil fuels geothermal regulation renewable energy reporting solar water security wind energy energy transition sustainable finance Scope 3 artificial intelligence SDGs 7. Energy 17. Partnerships

Abstract Flash floods endanger communities and ecosystems in rugged regions, but precise prediction is difficult due to environmental complexity. This study evaluates six machine learning algorithms for flash flood mapping in Iran’s Dez Basin, a region growing more vulnerable to climate extremes. We developed an integrated geospatial database incorporating 32 climatic, anthropogenic, and physiographic parameters, validated through extensive field surveys documenting historical flood events. The dataset (70% training, 30% validation) was analyzed using: (1) H2O Deep Learning framework, (2) Random Forest (RF), and (3) four boosting methods (AdaBoost, XGBoost, LightGBM, CatBoost). The RF model achieved exceptional predictive performance (AUC = 0.89, accuracy = 95%), outperforming other techniques by 6–12% in classification metrics. Sensitivity analysis identified precipitation intensity (β = 0.34, p  0.85) to enhance community resilience. 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Google Scholar Download references Author information Authors and Affiliations Department of Watershed Management Engineering, Faculty of Natural Resources, Lorestan University, Khorramabad, Iran Hafez Mirzapour, Ali Haghizadeh & Mahdi Soleimani Motlagh Authors Hafez Mirzapour View author publications Search author on:PubMed Google Scholar Ali Haghizadeh View author publications Search author on:PubMed Google Scholar Mahdi Soleimani Motlagh View author publications Search author on:PubMed Google Scholar Contributions AH, HM; Methodology: AH, HM; Formal analysis and investigation: AH, HM, MS; Writing—original draft preparation: AH, HM; Writing— review and editing: AH, HM, MS; Supervision: AH. All authors read and approved the final manuscript. Corresponding author Correspondence to Ali Haghizadeh. Ethics declarations Competing interests The authors declare no competing interests. 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Abstract Cities are highly vulnerable to climate change, yet the interactions between urban and regional climate remain insufficiently understood, especially over climate changes timescales and when comparing cities globally. Therefore, this study assesses the capabilities of two CORDEX-CORE regional climate models (REMO and RegCM) in representing urban areas globally, focusing on land-surface characteristics and urban heat island (UHI) evaluation. Despite their relatively coarse resolution (~25 km), the two models can capture urban imprints of large cities. RegCM, with a single-layer urban canopy parameterization, represents the UHI, especially at night. REMO tends to underestimate nighttime UHI due to its simple bulk urban scheme. Across models, impervious surface areas are consistently underestimated, with notable geographic imbalances across the world. Going forward, regional climate model simulations for cities require both enhanced urban parameterizations and the integration of refined urban land-use data. Data availability CORDEX-CORE and EURO-CORDEX data for daily maximum and minimum near surface temperature, orography, and land area fraction are publicly available through ESGF (https://esgf-data.dkrz.de/search/cordex-dkrz/). Urban and impervious surface area (ISA) fractions were collected and post-processed as part of this work and have been made publicly available on Zenodo (v1.0.0, https://doi.org/10.5281/zenodo.15700266). In addition, we provide detailed summary statistics for ISA - covering all cities, reference products, and model outputs, including mean values, percentiles (P0, 5, 25, 50, 75, 90, 100), and the number of pixels exceeding ISA thresholds of 0 and 0.1—available as both GeoJSON and CSV files on Zenodo (v1, https://doi.org/10.5281/zenodo.17313478). Code availability The Python code for city selection, impervious surface fraction calculation and related tasks is available on GitHub (https://github.com/FPS-URB-RCC/CORDEX-CORE-WG). The Python code for the urban heat island analysis is also available on GitHub (https://github.com/FPS-URB-RCC/urclimask). References Dodman, D. et al. Cities, settlements and key infrastructure. In Climate Change 2022: Impacts, Adaptation and Vulnerability. Working Group II Contribution to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [eds. Pörtner, H.-O. et al.] 907–1040 (Cambridge University Press, USA). UN Habitat. Guiding Principles for City Climate Action Planning. 40 https://unhabitat.org/guiding-principles-for-city-climate-action-planning (2015). Masson, V., Lemonsu, A., Hidalgo, J. & Voogt, J. Urban Climates and Climate Change. Annu. Rev. Environ. Resour. 45, 411–444 (2020). Google Scholar Oke, T. R., Mills, G., Christen, A. & Voogt, J. A. 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D.R. acknowledges support from the European Union’s HORIZON project FOCAL - Efficient Exploration of Climate Data Locally—under grant agreement No.101137787. J.F. acknowledges support from the European Union’s HORIZON Research and Innovation Actions under grant agreement No 101081555, project IMPETUS4CHANGE. G.S.L. and J.F. acknowledge support from project PROTECT (PID2023-149997OA-I00), funded by MICIU/AEI/10.13039/501100011033 and by ERDF/EU. T.H. acknowledges support from the European Union’s HORIZON Research and Innovation Actions under grant agreement No 101081555, project IMPETUS4CHANGE and by the Johannes Amos Comenius Programme (OP JAC) project No. CZ.02.01.01/00/22_008/0004605, Natural and anthropogenic georisk. Author information Authors and Affiliations Climate Adaptation and Disaster Risk Department, Deltares, Delft, the Netherlands Gaby S. Langendijk Instituto de Física de Cantabria (IFCA), CSIC-Universidad de Cantabria, Santander, Spain Jesus Fernandez, Javier Diez-Sierra & Yaiza Quintana B-Kode VOF, Ghent, Belgium Matthias Demuzere Facultad de Ciencias Exactas y Naturales (FCEN), Universidad de Buenos Aires (UBA), Buenos Aires, Argentina Lluis Fita, Natalia Zazulie, Andrea F. Carril & Luis E. Muñoz Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina Lluis Fita, Natalia Zazulie & Andrea F. Carril Instituto Franco-Argentino Para el Estudio del Clima y sus Impactos (IRL IFAECI/UBA-CONICET-CNRS-IRD), Buenos Aires, Argentina Lluis Fita, Andrea F. Carril & Luis E. Muñoz The Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy Natalia Zazulie, Rita Nogherotto & Graziano Giuliani The Institute of Atmospheric Sciences and Climate of the Italian National Research Council (CNR-ISAC), Bologna, Italy Rita Nogherotto University of the West of England, Bristol, UK Kwok Pan Chun Charles University, Faculty of Mathematics and Physics, Department of Atmospheric Physics, Prague, Czechia Tomas Halenka Climate Service Center Germany (GERICS), Helmholtz-Zentrum Hereon, Hamburg, Germany Peter Hoffmann, Joni-Pekka Pietikäinen & Diana Rechid Department of Atmospheric and Oceanic Sciences & Institute of Atmospheric Sciences, Fudan University, Shanghai, China Jiacan Yuan Authors Gaby S. Langendijk View author publications Search author on:PubMed Google Scholar Jesus Fernandez View author publications Search author on:PubMed Google Scholar Matthias Demuzere View author publications Search author on:PubMed Google Scholar Javier Diez-Sierra View author publications Search author on:PubMed Google Scholar Yaiza Quintana View author publications Search author on:PubMed Google Scholar Lluis Fita View author publications Search author on:PubMed Google Scholar Natalia Zazulie View author publications Search author on:PubMed Google Scholar Rita Nogherotto View author publications Search author on:PubMed Google Scholar Andrea F. Carril View author publications Search author on:PubMed Google Scholar Kwok Pan Chun View author publications Search author on:PubMed Google Scholar Graziano Giuliani View author publications Search author on:PubMed Google Scholar Tomas Halenka View author publications Search author on:PubMed Google Scholar Peter Hoffmann View author publications Search author on:PubMed Google Scholar Luis E. Muñoz View author publications Search author on:PubMed Google Scholar Joni-Pekka Pietikäinen View author publications Search author on:PubMed Google Scholar Diana Rechid View author publications Search author on:PubMed Google Scholar Jiacan Yuan View author publications Search author on:PubMed Google Scholar Contributions G.S.L., T.H., and P.H. initiated the study as part of the CORDEX FPS URB-RCC proposal. G.S.L., J.F., M.D., and J.D.S. developed the conceptual approach together with the rest of co-authors. M.D. conducted the land-use analysis. J.F., J.D.S., Y.Q., and G.S.L. conducted the urban heat island analysis. G.S.L., J.F., M.D., J.D.S., L.F., N.Z., R.N., K.P.C., T.H., J.Y., P.H., and J.P.P. developed the city selection approach, and G.S.L., J.F., J.D.S., L.F., N.Z., and R.N. conducted the associated analysis. J.P.P. and G.G. produced the urban fraction data from the models. G.S.L., J.F., M.D., and J.D.S. took the lead on writing the manuscript. Y.Q., L.F., N.Z., R.N., A.F.C., K.P.C., G.G., T.H., P.H., L.E.M., J.P.P., D.R., and J.Y. revised and improved the initial draft. All authors contributed to writing and revising the manuscript. Corresponding author Correspondence to Jesus Fernandez. Ethics declarations Competing interests The authors declare no competing interests. Additional information Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Supplementary information Supplementary information Rights and permissions Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. Reprints and permissions About this article Cite this article Langendijk, G.S., Fernandez, J., Demuzere, M. et al. Representation of global mega-cities and their urban heat island in CORDEX-CORE regional climate model simulations. npj Urban Sustain (2025). https://doi.org/10.1038/s42949-025-00325-6 Download citation Received: 22 June 2025 Accepted: 12 December 2025 Published: 30 December 2025 DOI: https://doi.org/10.1038/s42949-025-00325-6 Share this article Anyone you share the following link with will be able to read this content:Get shareable link Sorry, a shareable link is not currently available for this article. Copy shareable link to clipboard Provided by the Springer Nature SharedIt content-sharing initiative Subjects Atmospheric science Climate change Climate sciences

Abstract This study identifies atmospheric rivers (ARs) as key mediators linking large-scale climate teleconnections, the El Niño-Southern Oscillation (ENSO), Pacific-North American pattern (PNA), and Arctic Oscillation (AO), to variations in vegetation activity (NDVI) and burned area (BA) across North America. The results highlight the central role of ARs in shaping regional fire regimes and improving prospects for seasonal fire prediction. Distinct spatial and lag-dependent responses emerge: ENSO-driven precipitation promotes vegetation greening in northwestern Canada at longer lags, whereas browning dominates Alaska and northeastern Canada. The PNA exerts a dominant influence, suppressing NDVI across the eastern United States and central Canada at longer lags, while promoting greening in Alaska at shorter ones. AO effects often counter those of ENSO, driving vegetation drying in the southern United States and southwestern Canada at short lags, and in central Canada and Alaska at longer timescales. ARs exert a strong control over burned area, particularly across northern Canada and Alaska. When AR variability is incorporated, much of the fire enhancement previously attributed to teleconnection phases is reversed, indicating that AR-teleconnection interactions play a pivotal role in modulating the timing and magnitude of vegetation and fire responses across North America. Data availability Code to replicate these analyses are available at the Zenodo https://doi.org/10.5281/zenodo.17860684. The SLP, U10, V10 and T2m used here are public available at the ERA5 website https://cds.climate.copernicus.eu/datasets/reanalysis-era5-single-levels-monthly-means?tab=overview. Atmospheric rivers frequency and precipitation are available at UCLA website https://ucla.app.box.com/v/arcatalog/. 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The CNPq funding 441744/2024-9 and 303882/2020, and the BPCRC Polar Meteorology Development Fund. Dr. Bin Guan provided the AR code. Author information Authors and Affiliations Departamento de Engenharia Agrícola, Universidade Federal de Viçosa, Viçosa, MG, Brazil Flavio Justino & Carlos Gurjão Byrd Polar and Climate Research Center, The Ohio State University, Columbus, OH, USA David H. Bromwich Authors Flavio Justino View author publications Search author on:PubMed Google Scholar David H. Bromwich View author publications Search author on:PubMed Google Scholar Carlos Gurjão View author publications Search author on:PubMed Google Scholar Contributions F.J., D.H.B., and C.G. designed the study. C.G. performed data processing and plotting, and F.J. and D.H.B. wrote a large portion of the manuscript. Corresponding author Correspondence to Flavio Justino. Ethics declarations Competing interests The authors declare no competing interests. Peer review Peer review information Communications Earth and Environment thanks the anonymous reviewers for their contribution to the peer review of this work. Primary Handling Editors: Nicola Colombo and Aliénor Lavergne. A peer review file is available. Additional information Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Supplementary information Supplementary Information Transparent Peer Review file Rights and permissions Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/. Reprints and permissions About this article Cite this article Justino, F., Bromwich, D.H. & Gurjão, C. Atmospheric rivers as mediators between climate teleconnections and burned area variability in North America. Commun Earth Environ (2025). https://doi.org/10.1038/s43247-025-03124-0 Download citation Received: 17 June 2025 Accepted: 09 December 2025 Published: 30 December 2025 DOI: https://doi.org/10.1038/s43247-025-03124-0 Share this article Anyone you share the following link with will be able to read this content:Get shareable link Sorry, a shareable link is not currently available for this article. Copy shareable link to clipboard Provided by the Springer Nature SharedIt content-sharing initiative Subjects Climate sciences Environmental sciences

Abstract Under multiple anthropogenic global warming scenarios considered by the Coupled Model Intercomparison Project Phase 6 (CMIP6), Arctic sea ice is projected to disappear seasonally as early as 2035. Stratospheric Aerosol Injection (SAI) is a climate intervention strategy that has been proposed to mitigate some of the impacts of global warming. In this study, we evaluate the effectiveness of SAI in preserving Arctic sea ice, focusing on its sensitivity to the injection latitude of the aerosols. Using the 2nd version of the Community Earth System Model (CESM2) coupled with the Whole Atmosphere Community Climate Model (WACCM6), we analyze experiments with aerosol injection latitudes ranging from 45°S to 45°N. The results reveal that as the injection latitude shifts closer to the North Pole, Arctic sea ice rapidly recovers in both its extent and volume. This recovery is driven by coordinated shifts in clear-sky and cloud-related radiation, along with changes in surface reflectivity, that collectively reshape the surface energy balance in favor of ice growth. Importantly, we also find that, under fixed SAI injection rates, Arctic sea ice recovery varies substantially with injection latitude and does not scale directly with global mean surface temperature. Data availability The CESM2-WACCM6 simulation datasets generated and analyzed during this study are available from the corresponding authors upon reasonable request. Observational SIC data from the NOAA/NSIDC Climate Data Record (Version 3) are publicly available at https://nsidc.org/data/g02202/versions/3, while SIT data from the Pan-Arctic Ice Ocean Modeling and Assimilation System can be accessed at https://psc.apl.uw.edu/research/projects/arctic-sea-ice-volume-anomaly/data/model_grid. Codes for this study are available upon reasonable requests from H.K. (first author). 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Hyemi Kim was supported by the National Research Foundation of Korea (RS-2023-00278113), the Korea Meteorological Administration Research and Development Program (RS-2025-02313090), and the Ewha Womans University Research Grant of 2023. Author information Authors and Affiliations Department of Science Education, Ewha Womans University, Seoul, Korea Hyerim Kim & Hyemi Kim Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY, USA Daniele Visioni Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, Boulder, CO, USA Ewa M. Bednarz NOAA Chemical Sciences Laboratory (NOAA CSL), Boulder, CO, USA Ewa M. Bednarz Authors Hyerim Kim View author publications Search author on:PubMed Google Scholar Hyemi Kim View author publications Search author on:PubMed Google Scholar Daniele Visioni View author publications Search author on:PubMed Google Scholar Ewa M. Bednarz View author publications Search author on:PubMed Google Scholar Contributions H.K. (first author) and H.K. (corresponding author) designed the original ideas of the study. H.K. (first author) performed the data analysis and wrote the original manuscript. D.V. and E.M.B. contributed to the interpretation of the results and improvement of the manuscript. All authors have read and approved the manuscript. Corresponding author Correspondence to Hyemi Kim. Ethics declarations Competing interests The authors declare no competing interests. Additional information Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Supplementary information Supplementary information. Rights and permissions Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. Reprints and permissions About this article Cite this article Kim, H., Kim, H., Visioni, D. et al. Sensitivity of Arctic sea ice recovery to stratospheric aerosol injection latitude. npj Clim Atmos Sci (2025). https://doi.org/10.1038/s41612-025-01298-0 Download citation Received: 22 October 2025 Accepted: 08 December 2025 Published: 30 December 2025 DOI: https://doi.org/10.1038/s41612-025-01298-0 Share this article Anyone you share the following link with will be able to read this content:Get shareable link Sorry, a shareable link is not currently available for this article. Copy shareable link to clipboard Provided by the Springer Nature SharedIt content-sharing initiative Subjects Climate sciences Environmental sciences