A methodology to compile multi-hazard interrelationships in a data-scarce setting: an application to the Kathmandu Valley, Nepal Natural Hazards and Earth System Sciences DOI 10.5194/nhess-25-353-2025 27 January 2025 We present a methodology to compile single hazards and multi-hazard interrelationships in data-scarce urban settings, which we apply to the Kathmandu Valley, Nepal. Using blended sources, we collate evidence of 21 single natural hazard types and 83 multi-hazard interrelationships that could impact the Kathmandu Valley. We supplement these exemplars with multi-hazard scenarios developed by practitioner stakeholders, emphasising the need for inclusive disaster preparedness and response approaches. Read more
Spatial identification of regions exposed to multi-hazards at the pan-European level Natural Hazards and Earth System Sciences DOI 10.5194/nhess-25-287-2025 24 January 2025 This is the first study that uses spatial patterns (clusters/hotspots) and meta-analysis in order to identify the regions at a European level at risk of multi-hazards. The findings point out the socioeconomic dimension as a determining factor in the potential risk of multi-hazards. The outcome provides valuable input for the disaster risk management policy support and will assist national authorities on the implementation of a multi-hazard approach in national risk assessment preparation. Read more
Impacts from cascading multi-hazards using hypergraphs: a case study from the 2015 Gorkha earthquake in Nepal Natural Hazards and Earth System Sciences DOI 10.5194/nhess-25-267-2025 22 January 2025 Natural hazards like earthquakes often trigger other disasters, such as landslides, creating complex chains of impacts. We developed a risk model using a mathematical approach called hypergraphs to efficiently measure the impact of interconnected hazards. We showed that it can predict broad patterns of damage to buildings and roads from the 2015 Nepal earthquake. The model’s efficiency allows it to generate multiple disaster scenarios, even at a national scale, to support preparedness plans. Read more
Efficiency metrics for ocean alkalinity enhancements under responsive and prescribed atmospheric pCO2 conditions Biogeosciences DOI 10.5194/bg-22-341-2025 20 January 2025 Marine CO2 removal (mCDR) is a promising technology for removing legacy emissions from the atmosphere. Its indirect nature makes it difficult to assess experimentally; instead one relies heavily on simulation. Many past papers have treated the atmosphere as non-responsive to the intervention studied. We show that even under these simplified assumptions, the increase in ocean CO2 inventory is equal to the equivalent quantity of direct CO2 removals occurring over time, in a realistic atmosphere. Read more
Ensemble estimates of global wetland methane emissions over 2000–2020 Biogeosciences DOI 10.5194/bg-22-305-2025 17 January 2025 This study assesses global methane emissions from wetlands between 2000 and 2020 using multiple models. We found that wetland emissions increased by 6–7 Tg CH4 yr-1 in the 2010s compared to the 2000s. Rising temperatures primarily drove this increase, while changes in precipitation and CO2 levels also played roles. Our findings highlight the importance of wetlands in the global methane budget and the need for continuous monitoring to understand their impact on climate change. Read more
Integrating wide-swath altimetry data into Level-4 multi-mission maps Ocean Science DOI 10.5194/os-21-63-2025 15 January 2025 The Surface Water and Ocean Topography (SWOT) mission provides unprecedented swath altimetry data. This study examines SWOT’s impact on mapping systems, showing a moderate effect with the current nadir altimetry constellation and a stronger impact with a reduced one. Integrating SWOT with dynamic mapping techniques improves the resolution of satellite-derived products, offering promising solutions for studying and monitoring sea-level variability at finer scales. Read more
A topographically controlled tipping point for complete Greenland ice sheet melt The Cryosphere DOI 10.5194/tc-19-63-2025 13 January 2025 Anthropogenic warming is causing accelerated Greenland ice sheet melt. Here, we use a computer model to understand how prolonged warming and ice melt could threaten ice sheet stability. We find a threshold beyond which Greenland will lose more than 80 % of its ice over several thousand years, due to the interaction of surface and solid-Earth processes. Nearly complete Greenland ice sheet melt occurs when the ice margin disconnects from a region of high elevation in western Greenland. Read more
Particle fluxes by subtropical pelagic communities under ocean alkalinity enhancement Biogeosciences DOI 10.5194/bg-22-71-2025 10 January 2025 Ocean alkalinity enhancement (OAE) is a negative emission technology which may alter marine communities and the particle export they drive. Here, impacts of carbonate-based OAE on the flux and attenuation of sinking particles in an oligotrophic plankton community are presented. Whilst biological parameters remained unaffected, abiotic carbonate precipitation occurred. Among counteracting OAE’s efficiency, it influenced mineral ballasting and particle sinking velocities, requiring monitoring. Read more
Evaluating downscaled products with expected hydroclimatic co-variances Geoscientific Model Development DOI 10.5194/gmd-17-8665-2024 25 December 2024 We evaluate downscaled products by examining locally relevant co-variances during precipitation events. Common statistical downscaling techniques preserve expected co-variances during convective precipitation (a stationary phenomenon). However, they dampen future intensification of frontal precipitation (a non-stationary phenomenon) captured in global climate models and dynamical downscaling. Our study quantifies a ramification of the stationarity assumption underlying statistical downscaling. Read more
Warming effects of reduced sulfur emissions from shipping Atmospheric Chemistry and Physics DOI 10.5194/acp-24-13681-2024 24 December 2024 A 2020 regulation has reduced sulfur emissions from shipping by about 80 %, leading to a decrease in atmospheric aerosols that have a cooling effect primarily by affecting cloud properties and amounts. Our climate model simulations predict a global temperature increase of 0.04 K over the next 3 decades as a result, which could contribute to surpassing the Paris Agreement’s 1.5 °C target. Reduced aerosols may have also contributed to the recent temperature spikes. Read more
