Uncertainty-informed selection of CMIP6 Earth system model subsets for use in multisectoral and impact models Earth System Dynamics DOI 10.5194/esd-15-1301-2024 15 October 2024 From running climate models to using their outputs to identify impacts, modeling the integrated human–Earth system is expensive. This work presents a method to identify a smaller subset of models from the full set that preserves the uncertainty characteristics of the full set. This results in a smaller number of runs that an impact modeler can use to assess how uncertainty propagates from the Earth to the human system, while still capturing the range of outcomes provided by climate models. Read more
The spatio-temporal evolution of the Chongzhen drought (1627–1644) in China and its impact on famine Climate of the Past DOI 10.5194/cp-20-2287-2024 14 October 2024 This study used 1802 drought and 1977 famine records from historical documents to reconstruct the spatial–temporal progression of the Chongzhen drought (1627–1644) in China and its impacts. We advance this research by reconstructing the annual spatial patterns and regional series of drought; demonstrating drought as the primary factor triggering famine; and identifying the transmission pathway of the drought’s impacts and how social factors, especially human responses, regulated these impacts. Read more
Earth science for all? The economic barrier to European geoscience conferences Geoscience Communication DOI 10.5194/gc-7-245-2024 14 October 2024 Conferences are key for knowledge exchange and networking. However, these events lack diversity, favoring wealthier countries and limiting opportunities for scholars from lower-income regions. Our study of the EGU meeting reveals that attendance is mostly influenced by a country’s income. To promote inclusivity, we suggest rotating event locations, offering affordable accommodations, and establishing travel funds. These steps can help create a more diverse and innovative scientific community. Read more
The 2023 global warming spike was driven by the El Niño–Southern Oscillation Atmospheric Chemistry and Physics DOI 10.5194/acp-24-11275-2024 14 October 2024 The rapid global warming of 2023 has led to concerns that it could be externally driven. Here we show that climate models subject only to internal variability predict such warming spikes but rarely (p~1.6 %). However, when a prolonged La Niña immediately precedes an El Niño, as occurred leading up to 2023, such spikes are not uncommon (p~10.3 %). Virtually all of the spikes occur during an El Niño, strongly suggesting that internal variability drove the 2023 warming. Read more
Stable and unstable fall motions of plate-like ice crystal analogues Atmospheric Chemistry and Physics DOI 10.5194/acp-24-11133-2024 14 October 2024 This study uses 3D-printed ice crystal analogues falling in a water–glycerine mix and observed with multi-view cameras, simulating atmospheric conditions. Four types of motion are observed: stable, zigzag, transitional, and spiralling. Particle shape strongly influences motion; complex shapes have a wider range of conditions where they fall steadily compared to simple plates. The most common orientation of unstable particles is non-horizontal, contrary to prior assumptions of always horizontal. Read more
Characterizing nonlinear, nonstationary, and heterogeneous hydrologic behavior using ensemble rainfall–runoff analysis (ERRA): proof of concept Hydrology and Earth System Sciences DOI 10.5194/hess-28-4427-2024 11 October 2024 Here, I present a new way to quantify how streamflow responds to rainfall across a range of timescales. This approach can estimate how different rainfall intensities affect streamflow. It can also quantify how runoff response to rainfall varies, depending on how wet the landscape already is before the rain falls. This may help us to understand processes and landscape properties that regulate streamflow and to assess the susceptibility of different landscapes to flooding Read more
Global-scale gravity wave analysis methodology for the ESA Earth Explorer 11 candidate CAIRT Atmospheric Measurement Techniques DOI 10.5194/amt-17-5785-2024 4 October 2024 We investigate the capabilities of a proposed satellite mission, CAIRT, for observing gravity waves throughout the middle atmosphere and present the necessary methodology for in-depth wave analysis. Our findings suggest that such a satellite mission is highly capable of resolving individual wave parameters and could give new insights into the role of gravity waves in general atmospheric circulation and atmospheric processes. Read more
The effects of land use on soil carbon stocks in the UK Biogeosciences DOI 10.5194/bg-21-4301-2024 4 October 2024 We collated a large data set (15 790 soil cores) on soil carbon stock in different land uses. Soil carbon stocks were highest in woodlands and lowest in croplands. The variability in the effects was large. This has important implications for agri-environment schemes seeking to sequester carbon in the soil by altering land use because the effect of a given intervention is very hard to verify. Read more
Calibrating estimates of ionospheric long-term change Annales Geophysicae DOI 10.5194/angeo-42-395-2024 27 September 2024 Long-term change in the ionosphere are expected due to increases in greenhouse gases in the lower atmosphere. Empirical formulae are used to estimate height. Through comparison with independent data we show that there are seasonal and long-term biases introduced by the empirical model. We conclude that estimates of long-term changes in ionospheric height need to account for these biases. Read more
Review article: Drought as a continuum – memory effects in interlinked hydrological, ecological, and social systems Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-3173-2024 23 September 2024 Drought is a creeping phenomenon but is often still analysed and managed like an isolated event, without taking into account what happened before and after. Here, we review the literature and analyse five cases to discuss how droughts and their impacts develop over time. We find that the responses of hydrological, ecological, and social systems can be classified into four types and that the systems interact. We provide suggestions for further research and monitoring, modelling, and management. Read more
Increasing aerosol optical depth spatial and temporal availability by merging datasets from geostationary and sun-synchronous satellites Atmospheric Measurement Techniques DOI 10.5194/amt-17-5455-2024 20 September 2024 In this study, for the first time, we combined aerosol data from six satellites using a unified algorithm. The global datasets are generated at a high spatial resolution of about 25 km with an interval of 30 min. The new datasets are compared against ground truth and verified. They will be useful for various applications such as air quality monitoring, climate research, pollution diurnal variability, long-range smoke and dust transport, and evaluation of regional and global models. Read more
Methane retrieval from MethaneAIR using the CO2 proxy approach: a demonstration for the upcoming MethaneSAT mission Atmospheric Measurement Techniques DOI 10.5194/amt-17-5429-2024 20 September 2024 MethaneSAT is an upcoming satellite mission designed to monitor methane emissions from the oil and gas (O&G) industry globally. Here, we present observations from the first flight campaign of MethaneAIR, a MethaneSAT-like instrument mounted on an aircraft. MethaneAIR can map methane with high precision and accuracy over a typically sized oil and gas basin (~200 km2) in a single flight. This paper demonstrates the capability of the upcoming satellite to routinely track global O&G emissions. Read more
Volcano tsunamis and their effects on moored vessel safety: the 2022 Tonga event Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-3095-2024 20 September 2024 The eruption of the Hunga Tonga–Hunga Ha’apai volcano in January 2022 triggered a global phenomenon, including an atmospheric wave and a volcano-meteorological tsunami (VMT). The tsunami, reaching as far as Callao, Peru, 10 000 km away, caused significant coastal impacts. This study delves into understanding these effects, particularly on vessel mooring safety. The findings underscore the importance of enhancing early warning systems and preparing port authorities for managing such rare events. Read more
The 2020 European Seismic Hazard Model: overview and results Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-3049-2024 20 September 2024 The 2020 European Seismic Hazard Model (ESHM20) is the latest seismic hazard assessment update for the Euro-Mediterranean region. This state-of-the-art model delivers a broad range of hazard results, including hazard curves, maps, and uniform hazard spectra. ESHM20 provides two hazard maps as informative references in the next update of the European Seismic Design Code (CEN EC8), and it also provides a key input to the first earthquake risk model for Europe. Read more
Large-sample hydrology – a few camels or a whole caravan? Hydrology and Earth System Sciences DOI 10.5194/hess-28-4219-2024 20 September 2024 We show that the differences between the forcing data included in three CAMELS datasets (US, BR, GB) and the forcing data included for the same catchments in the Caravan dataset affect model calibration considerably. The model performance dropped when the data from the Caravan dataset were used instead of the original data. Most of the model performance drop could be attributed to the differences in precipitation data. However, differences were largest for the potential evapotranspiration data. Read more
The EarthCARE lidar cloud and aerosol profile processor (A-PRO): the A-AER, A-EBD, A-TC, and A-ICE products Atmospheric Measurement Techniques DOI 10.5194/amt-17-5301-2024 20 September 2024 ATLID (atmospheric lidar) is the lidar to be flown on the Earth Clouds and Radiation Explorer satellite (EarthCARE). EarthCARE is a joint European–Japanese satellite mission that was launched in May 2024. ATLID is an advanced lidar optimized for cloud and aerosol property profile measurements. This paper describes some of the key novel algorithms being applied to this lidar to retrieve cloud and aerosol properties. Example results based on simulated data are presented and discussed. Read more
Can we reliably reconstruct the mid-Pliocene Warm Period with sparse data and uncertain models? Climate of the Past DOI 10.5194/cp-20-1989-2024 20 September 2024 We have created a new global surface temperature reconstruction of the climate of the mid-Pliocene Warm Period, representing the period roughly 3.2 million years before the present day. We estimate that the globally averaged mean temperature was around 3.9 °C warmer than it was in pre-industrial times, but there is significant uncertainty in this value. Read more
Biological and dust aerosols as sources of ice-nucleating particles in the eastern Mediterranean: source apportionment, atmospheric processing and parameterization Atmospheric Chemistry and Physics DOI 10.5194/acp-24-9939-2024 20 September 2024 Ice nucleating particle (INP) concentrations are required for correct predictions of clouds and precipitation in a changing climate, but they are poorly constrained in climate models. We unravel source contributions to INPs in the eastern Mediterranean and find that biological particles are important, regardless of their origin. The parameterizations developed exhibit superior performance and enable models to consider biological-particle effects on INPs. Read more
CO2 emissions of drained coastal peatlands in the Netherlands and potential emission reduction by water infiltration systems Biogeosciences DOI 10.5194/bg-21-4099-2024 20 September 2024 Drained peatlands cause high CO2 emissions. We assessed the effectiveness of subsurface water infiltration systems (WISs) in reducing CO2 emissions related to increases in water table depth (WTD) on 12 sites for up to 4 years. Results show WISs markedly reduced emissions by 2.1 t CO2-C ha-1 yr-1. The relationship between the amount of carbon above the WTD and CO2 emission was stronger than the relationship between WTD and emission. Long-term monitoring is crucial for accurate emission estimates. Read more
Young and new water fractions in soil and hillslope waters Hydrology and Earth System Sciences DOI 10.5194/hess-28-4295-2024 20 September 2024 We use a 3-year time series of tracer data of streamflow and soils to show how water moves through the subsurface to become streamflow. Less than 50% of soil water consists of rainfall from the last 3 weeks. Most annual streamflow is older than 3 months, and waters in deep subsurface layers are even older; thus deep layers are not the only source of streamflow. After wet periods more rainfall was found in the subsurface and the stream, suggesting that water moves quicker through wet landscapes. Read more
Representation learning with unconditional denoising diffusion models for dynamical systems Nonlinear Processes in Geophysics DOI 10.5194/npg-31-409-2024 19 September 2024 We train neural networks as denoising diffusion models for state generation in the Lorenz 1963 system and demonstrate that they learn an internal representation of the system. We make use of this learned representation and the pre-trained model in two downstream tasks: surrogate modelling and ensemble generation. For both tasks, the diffusion model can outperform other more common approaches. Thus, we see a potential of representation learning with diffusion models for dynamical systems. Read more
Mesoscale permeability variations estimated from natural airflows in the decorated Cosquer Cave (southeastern France) Hydrology and Earth System Sciences DOI 10.5194/hess-28-4035-2024 6 September 2024 Conservation of decorated caves is highly dependent on airflows and is correlated with rock formation permeability. We present the first conceptual model of flows around the Paleolithic decorated Cosquer coastal cave (southeastern France), quantify air permeability, and show how its variation affects water levels inside the cave. This study highlights that airflows may change in karst unsaturated zones in response to changes in the water cycle and may thus be affected by climate change. Read more
Precursors and pathways: dynamically informed extreme event forecasting demonstrated on the historic Emilia-Romagna 2023 flood Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-2995-2024 6 September 2024 Extreme rainfall is the leading weather-related source of damages in Europe, but it is still difficult to predict on long timescales. A recent example of this was the devastating floods in the Italian region of Emiglia Romagna in May 2023. We present perspectives based on large-scale dynamical information that allows us to better understand and predict such events. Read more
Ice viscosity governs hydraulic fracture that causes rapid drainage of supraglacial lakes The Cryosphere DOI 10.5194/tc-18-3991-2024 6 September 2024 Due to surface melting, meltwater lakes seasonally form on the surface of glaciers. These lakes drive hydrofractures that rapidly transfer water to the base of ice sheets. This paper presents a computational method to capture the complicated hydrofracturing process. Our work reveals that viscous ice rheology has a great influence on the short-term propagation of fractures, enabling fast lake drainage, whereas thermal effects (frictional heating, conduction, and freezing) have little influence. Read more
Optimizing the iodide-adduct chemical ionization mass spectrometry (CIMS) quantitative method for toluene oxidation intermediates: experimental insights into functional-group differences Atmospheric Measurement Techniques DOI 10.5194/amt-17-5113-2024 6 September 2024 We introduce detailed and improved quantitation and semi-quantitation methods of iodide-adduct time-of-flight chemical ionization mass spectrometry (I-CIMS) to measure toluene oxidation intermediates. We assess the experimental sensitivity of various functional group species and their binding energy with iodide ions in I-CIMS. A novel classification approach was introduced to significantly enhance the accuracy of semi-quantitative methods (improving R2 values from 0.52 to beyond 0.88). Read more
How is particulate organic carbon transported through the river-fed submarine Congo Canyon to the deep sea? Biogeosciences DOI 10.5194/bg-21-4251-2024 6 September 2024 The land-to-ocean flux of particulate organic carbon (POC) is difficult to measure, inhibiting accurate modeling of the global carbon cycle. Here, we quantify the POC flux between one of the largest rivers on Earth (Congo) and the ocean. POC in the form of vegetation and soil is transported by episodic submarine avalanches in a 1000 km long canyon at up to 5 km water depth. The POC flux induced by avalanches is at least 3 times greater than that induced by the background flow related to tides. Read more
The crucial representation of deep convection for the cyclogenesis of Medicane Ianos Weather and Climate Dynamics DOI 10.5194/wcd-5-1187-2024 6 September 2024 Cyclone Ianos of September 2020 was a high-impact but poorly predicted medicane (Mediterranean hurricane). A community effort of numerical modelling provides robust results to improve prediction. It is found that the representation of local thunderstorms controlled the interaction of Ianos with a jet stream at larger scales and its subsequent evolution. The results help us understand the peculiar dynamics of medicanes and provide guidance for the next generation of weather and climate models. Read more
Merging modelled and reported flood impacts in Europe in a combined flood event catalogue for 1950–2020 Hydrology and Earth System Sciences DOI 10.5194/hess-28-3983-2024 2 September 2024 Long-term trends in flood losses are regulated by multiple factors, including climate variation, population and economic growth, land-use transitions, reservoir construction, and flood risk reduction measures. Here, we reconstruct the factual circumstances in which almost 15 000 potential riverine, coastal and compound floods in Europe occurred between 1950 and 2020. About 10 % of those events are reported to have caused significant socioeconomic impacts. Read more
Late Quaternary glacial maxima in southern Patagonia: insights from the Lago Argentino glacier lobe Climate of the Past DOI 10.5194/cp-20-1861-2024 30 August 2024 Investigating past glaciated regions is crucial for understanding how ice sheets responded to climate forcings and how they might respond in the future. We use two independent dating techniques to document the timing and extent of the Lago Argentino glacier lobe, a former lobe of the Patagonian Ice Sheet, during the late Quaternary. Our findings highlight feedbacks in the Earth’s system responsible for modulating glacier growth in the Southern Hemisphere prior to the global Last Glacial Maximum. Read more
Cautionary remarks on the planetary boundary visualisation Earth System Dynamics DOI 10.5194/esd-15-1153-2024 26 August 2024 Our paper examines the visual representation of the planetary boundary concept, which helps convey Earth’s capacity to sustain human life. We identify three issues: exaggerated impact sizes, confusing color patterns, and inaccessibility for colour-vision deficiency. These flaws can lead to overstating risks. We suggest improving these visual elements for more accurate and accessible information for decision-makers. Read more
An increase in the spatial extent of European floods over the last 70 years Hydrology and Earth System Sciences DOI 10.5194/hess-28-3755-2024 23 August 2024 We use grid-based runoff from a hydrological model to identify large spatiotemporally connected flood events in Europe, assess extent trends over the last 70 years, and attribute the trends to different drivers. Our findings reveal a general increase in flood extent, with regional variations driven by diverse factors. The study not only enables a thorough examination of flood events across multiple basins but also highlights the potential challenges arising from changing flood extents. Read more
Always on my mind: indications of post-traumatic stress disorder among those affected by the 2021 flood event in the Ahr valley, Germany Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-2837-2024 23 August 2024 Despite the visible flood damage, mental health is a growing concern. Yet, there is limited data in Germany on mental health impacts after floods. A survey in a heavily affected region revealed that 28 % of respondents showed signs of post-traumatic stress disorder 1 year later. Risk factors include gender, serious injury or illness due to flooding, and feeling left alone to cope with impacts. The study highlights the need for tailored mental health support for flood-affected populations. Read more
Atmospheric H2 observations from the NOAA Cooperative Global Air Sampling Network Atmospheric Measurement Techniques DOI 10.5194/amt-17-4803-2024 23 August 2024 Hydrogen (H2) is a gas in trace amounts in the Earth’s atmosphere with indirect impacts on climate and air quality. Renewed interest in H2 as a low- or zero-carbon source of energy may lead to increased production, uses, and supply chain emissions. NOAA measurements of weekly air samples collected between 2009 and 2021 at over 50 sites in mostly remote locations are now available, and they complement other datasets to study the H2 global budget. Read more
Absence of causality between seismic activity and global warming Earth System Dynamics DOI 10.5194/esd-15-1015-2024 19 August 2024 It was recently suggested that global warming can be explained by the non-anthropogenic factor of seismic activity. If that is the case, it would have profound implications. We have assessed the validity of the claim by using a statistical technique that evaluates the existence of causal connections between variables, finding no evidence for any causal relationship between seismic activity and global warming. Read more
Tipping point detection and early warnings in climate, ecological, and human systems Earth System Dynamics DOI 10.5194/esd-15-1117-2024 19 August 2024 Tipping points are abrupt, rapid, and sometimes irreversible changes, and numerous approaches have been proposed to detect them in advance. Such approaches have been termed early warning signals and represent a set of methods for identifying changes in the underlying behaviour of a system across time or space that might indicate an approaching tipping point. Here, we review the literature to explore where, how, and which early warnings have been used in real-world case studies so far. Read more
Sourcing and long-range transport of particulate organic matter in river bedload: Río Bermejo, Argentina Earth Surface Dynamics DOI 10.5194/esurf-12-907-2024 19 August 2024 The transport of plant debris in rivers is an important part of the global carbon cycle and influences atmospheric carbon levels through time. We sampled plant debris at the bed of a lowland river and determined the sources as it is transported hundreds of kilometers. Plant debris can persist at the riverbed, but mechanical breakdown reduces its amount, and it is only a small fraction compared to the suspended load. This plant debris and transport patterns need further investigation globally. Read more
ESD Ideas: Exoplanet, origins of life and biosphere researchers offer a perspective fundamental to ensuring humanity’s future Earth System Dynamics DOI 10.5194/esd-15-929-2024 16 August 2024 Scientists exploring the histories of planets and life are uniquely positioned to communicate a perspective that is fundamental to our survival: humanity is wholly embedded in Earth and its biosphere. There is no escaping our planet and its history. Only policies that build on this perspective will contribute to a flourishing future for humanity. We offer a few brief glimpses of this cosmic perspective and call on our colleagues to acknowledge the powerful stories emanating from their work. Read more
Using historical temperature to constrain the climate sensitivity, the transient climate response, and aerosol-induced cooling Atmospheric Chemistry and Physics DOI 10.5194/acp-24-8105-2024 12 August 2024 Using errors in climate model simulations this paper derives correction factors for the impacts of greenhouse gases and particles that bring these simulated temperature fields into agreement with an observational reconstruction of the Earth’s temperature. On average across eight models, a reduction by about one-half of the particle-induced cooling would be required, causing only 0.24 K of cooling since 1850–1899. The greenhouse gas warming simulated by several highly sensitive models would also reduce. Read more
Continuous synchronization of the Greenland ice-core and U–Th timescales using probabilistic inversion Climate of the Past DOI 10.5194/cp-20-1415-2024 9 August 2024 The first continuously measured transfer functions that quantify the age difference between the Greenland ice-core chronology 2005 (GICC05) and the U–Th timescale are presented. The transfer functions were generated using a novel probabilistic algorithm for the synchronization of proxy signals. The results greatly improve the accuracy and precision of previous synchronization estimates and reveal that the annual-layer counting error of GICC05 is less systematic than previously assumed. Read more
Observation-inferred resilience loss of the Amazon rainforest possibly due to internal climate variability Earth System Dynamics DOI 10.5194/esd-15-913-2024 5 August 2024 We investigate whether the Amazon rainforest has lost substantial resilience since 1990. This assertion is based on trends in the observational record of vegetation density. We calculate the same metrics in a large number of climate model simulations and find that several models behave indistinguishably from the observations, suggesting that the observed trend could be caused by internal variability and that the cause of the ongoing rapid loss of Amazon rainforest is not mainly global warming. Read more
Can corporate supply chain sustainability standards contribute to soil protection? SOIL DOI 10.5194/soil-10-505-2024 2 August 2024 We explore business efforts to ensure soil quality in their supply chains through the application of supplier sustainability standards. Through a content analysis of existing sustainability standards and companies’ sustainability reports, we found that soil sustainability is an important priority for food retailers. However, the standards currently applied tend to have a limited impact on soil protection due to a lack of specific criteria and thresholds. Read more
Hydro-pedotransfer functions: a roadmap for future development Hydrology and Earth System Sciences DOI 10.5194/hess-28-3391-2024 29 July 2024 Pedotransfer functions (PTFs) are used to predict parameters of models describing the hydraulic properties of soils. The appropriateness of these predictions critically relies on the nature of the datasets for training the PTFs and the physical comprehensiveness of the models. This roadmap paper is addressed to PTF developers and users and critically reflects the utility and future of PTFs. To this end, we present a manifesto aiming at a paradigm shift in PTF research. Read more
Linking geomorphological processes and wildlife microhabitat selection: nesting birds select refuges generated by permafrost degradation in the Arctic Biogeosciences DOI 10.5194/bg-21-3401-2024 26 July 2024 In the Arctic tundra, climate change is transforming the landscape, and this may impact wildlife. We focus on three nesting bird species and the islets they select as refuges from their main predator, the Arctic fox. A geomorphological process, ice-wedge polygon degradation, was found to play a key role in creating these refuges. This process is likely to affect predator–prey dynamics in the Arctic tundra, highlighting the connections between nature’s physical and ecological systems. Read more
Brief communication: Storm Daniel flood impact in Greece in 2023: mapping crop and livestock exposure from synthetic-aperture radar (SAR) Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-2375-2024 22 July 2024 About 820 km2 of agricultural land was inundated in central Greece due to Storm Daniel. A detailed analysis revealed that the crop most affected by the flooding was cotton; the inundated area of more than 282 km2 comprised ~ 30 % of the total area planted with cotton in central Greece. In terms of livestock, we estimate that more than 14 000 ornithoids and 21 500 sheep and goats were affected. Consequences for agriculture and animal husbandry in Greece are expected to be severe. Read more
The risk of synoptic-scale Arctic cyclones to shipping Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-2115-2024 19 July 2024 The risk posed to ships by Arctic cyclones has seldom been quantified due to the lack of publicly available historical Arctic ship track data. This study investigates historical Arctic ship tracks, cyclone tracks, and shipping incident reports to determine the number of shipping incidents caused by the passage of Arctic cyclones. Results suggest that Arctic cyclones have not been hazardous to ships and that ships are resilient to the rough sea conditions caused by Arctic cyclones. Read more
Isotopomer labeling and oxygen dependence of hybrid nitrous oxide production Biogeosciences DOI 10.5194/bg-21-3215-2024 17 July 2024 Nitrous oxide, a potent greenhouse gas, accumulates in regions of the ocean that are low in dissolved oxygen. We used a novel combination of chemical tracers to determine how nitrous oxide is produced in one of these regions, the eastern tropical North Pacific Ocean. Our experiments showed that the two most important sources of nitrous oxide under low-oxygen conditions are denitrification, an anaerobic process, and a novel “hybrid” process performed by ammonia-oxidizing archaea. Read more
Coupled ice–ocean interactions during future retreat of West Antarctic ice streams in the Amundsen Sea sector The Cryosphere DOI 10.5194/tc-18-2653-2024 15 July 2024 A new ice–ocean model simulates future ice sheet evolution in the Amundsen Sea sector of Antarctica. Substantial ice retreat is simulated in all scenarios, with some retreat still occurring even with no future ocean melting. The future of small “pinning points” (islands of ice that contact the seabed) is an important control on this retreat. Ocean melting is crucial in causing these features to go afloat, providing the link by which climate change may affect this sector’s sea level contribution. Read more
Quantum data assimilation: a new approach to solving data assimilation on quantum annealers Nonlinear Processes in Geophysics DOI 10.5194/npg-31-237-2024 12 July 2024 Data assimilation is a crucial component in the Earth science field, enabling the integration of observation data with numerical models. In the context of numerical weather prediction (NWP), data assimilation is particularly vital for improving initial conditions and subsequent predictions. However, the computational demands imposed by conventional approaches, which employ iterative processes to minimize cost functions, pose notable challenges in computational time. The emergence of quantum computing provides promising opportunities to address these computation challenges by harnessing the inherent parallelism and optimization capabilities of quantum annealing machines. Read more
Elevation-dependent warming: observations, models, and energetic mechanisms Weather and Climate Dynamics DOI 10.5194/wcd-5-763-2024 10 July 2024 Observational data and numerical models suggest that, under climate change, elevated land surfaces warm faster than non-elevated ones. Proposed drivers of this “elevation-dependent warming” (EDW) include surface albedo and water vapour feedbacks, the temperature dependence of longwave emission, and aerosols. Yet the relative importance of each proposed mechanism both regionally and at large scales is unclear, highlighting an incomplete physical understanding of EDW. Read more
A downward-counterfactual analysis of flash floods in Germany Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-2147-2024 8 July 2024 To identify flash flood potential in Germany, we shifted the most extreme rainfall events from the last 22 years systematically across Germany and simulated the consequent runoff reaction. Our results show that almost all areas in Germany have not seen the worst-case scenario of flood peaks within the last 22 years. With a slight spatial change of historical rainfall events, flood peaks of a factor of 2 or more would be achieved for most areas. The results can aid disaster risk management. Read more