CH-RUN: a deep-learning-based spatially contiguous runoff reconstruction for Switzerland Hydrology and Earth System Sciences DOI 10.5194/hess-29-1061-2025 27 February 2025 This study reconstructs daily runoff in Switzerland (1962–2023) using a deep-learning model, providing a spatially contiguous dataset on a medium-sized catchment grid. The model outperforms traditional hydrological methods, revealing shifts in Swiss water resources, including more frequent dry years and declining summer runoff. The reconstruction is publicly available. Read more
Sensitivity of tropical orographic precipitation to wind speed with implications for future projections Weather and Climate Dynamics DOI 10.5194/wcd-6-231-2025 27 February 2025 Rainfall in mountainous regions constitutes an important source of freshwater in the tropics. Yet how it will change with global warming remains an open question. Here, we reveal a strong sensitivity of this rainfall to the speed of prevailing winds. This relationship, validated by theory, simulations, and observational data, suggests that regional wind shifts will significantly influence future rainfall changes in the tropics. Read more
Opinion: Why all emergent constraints are wrong but some are useful – a machine learning perspective Atmospheric Chemistry and Physics DOI 10.5194/acp-25-2365-2025 26 February 2025 In our article, we review uncertainties in global climate change projections and current methods using Earth observations as constraints, which is crucial for climate risk assessments and for informing society. We then discuss how machine learning can advance the field, discussing recent work that provides potentially stronger and more robust links between observed data and future climate projections. We further discuss the challenges of applying machine learning to climate science. Read more
Brief communication: Sea-level projections, adaptation planning, and actionable science The Cryosphere DOI 10.5194/tc-19-793-2025 25 February 2025 As communities try to adapt to climate change, they look for “actionable science” that can inform decision-making. There are risks in relying on novel results that are not yet accepted by the science community. We propose a practical criterion for determining which scientific claims are actionable. We show how premature acceptance of sea-level-rise predictions can lead to confusion and backtracking, and we suggest best practices for communication between scientists and adaptation planners. Read more
Synoptic perspective on the conversion and maintenance of local available potential energy in extratropical cyclones Weather and Climate Dynamics DOI 10.5194/wcd-6-211-2025 21 February 2025 Although extratropical cyclones in the North Atlantic are among the most impactful midlatitude weather systems, their intensification is not entirely understood. Here, we explore how individual cyclones convert available potential energy (APE) into kinetic energy and relate these conversions to the synoptic development of the cyclones. By combining potential vorticity thinking with a local APE framework, we offer a novel perspective on established concepts in dynamic meteorology. Read more
Toward more robust net primary production projections in the North Atlantic Ocean Biogeosciences DOI 10.5194/bg-22-841-2025 20 February 2025 The marine biogeochemistry components of Coupled Model Intercomparison Project phase 6 (CMIP6) models vary widely in their process representations. Using an innovative bioregionalization of the North Atlantic, we reveal that this model diversity largely drives the divergence in net primary production projections under a high-emission scenario. The identification of the most mechanistically realistic models allows for a substantial reduction in projection uncertainty. Read more
Creating a national urban flood dataset for China from news texts (2000–2022) at the county level Hydrology and Earth System Sciences DOI 10.5194/hess-29-767-2025 19 February 2025 We create China’s first open county-level urban flood dataset (2000–2022) using news media data with the help of deep learning. The dataset reflects both natural and societal influences and includes 7595 urban flood events across 2051 counties, covering 46 % of China’s land area. It reveals the predominance of summer floods, an upward trend since 2000, and a decline from southeast to northwest. Notably, some highly developed regions show a decrease, likely due to improved flood management. Read more
What controls planktic foraminiferal calcification? Biogeosciences DOI 10.5194/bg-22-791-2025 17 February 2025 Planktic foraminifers are a plankton whose fossilised shell weight is used to reconstruct past environmental conditions such as seawater CO2. However, there is debate about whether other environmental drivers impact shell weight. Here we use a global data compilation and statistics to analyse what controls their weight. We find that the response varies between species and ocean basin, making it important to use regional calibrations and consider which species should be used to reconstruct CO2. Read more
Moving beyond post hoc explainable artificial intelligence: a perspective paper on lessons learned from dynamical climate modeling Geoscientific Model Development DOI 10.5194/gmd-18-787-2025 14 February 2025 We draw from traditional climate modeling practices to make recommendations for machine-learning (ML)-driven climate science. Our intended audience is climate modelers who are relatively new to ML. We show how component-level understanding – obtained when scientists can link model behavior to parts within the overall model – should guide the development and evaluation of ML models. Better understanding yields a stronger basis for trust in the models. We highlight several examples to demonstrate. Read more
Causes of the exceptionally high number of fatalities in the Ahr valley, Germany, during the 2021 flood Natural Hazards and Earth System Sciences DOI 10.5194/nhess-25-581-2025 12 February 2025 In July 2021, flooding killed 190 people in Germany, 134 of them in the Ahr valley, making it the deadliest flood in recent German history. The flash flood was extreme in terms of water levels, flow velocities and flood extent, and early warning and evacuation were inadequate. Many died on the ground floor or in the street, with older and impaired individuals especially vulnerable. Clear warnings should urge people to seek safety rather than save belongings, and timely evacuations are essential. Read more
