Improving hydrologic models for predictions and process understanding using neural ODEs Hydrology and Earth System Sciences DOI 10.5194/hess-26-5085-2022 23 December 2022 Neural ODEs fuse physics-based models with deep learning: neural networks substitute terms in differential equations that represent the mechanistic structure of the system. The approach combines the flexibility of machine learning with physical constraints for inter- and extrapolation. We demonstrate that neural ODE models achieve state-of-the-art predictive performance while keeping full interpretability of model states and processes in hydrologic modelling over multiple catchments. Read more
The Antarctic contribution to 21st-century sea-level rise predicted by the UK Earth System Model with an interactive ice sheet The Cryosphere DOI 10.5194/tc-16-4053-2022 21 December 2022 The UK Earth System Model is the first to fully include interactions of the atmosphere and ocean with the Antarctic Ice Sheet. Under the low-greenhouse-gas SSP1–1.9 (Shared Socioeconomic Pathway) scenario, the ice sheet remains stable over the 21st century. Under the strong-greenhouse-gas SSP5–8.5 scenario, the model predicts strong increases in melting of large ice shelves and snow accumulation on the surface. The dominance of accumulation leads to a sea level fall at the end of the century. Read more
Predicting soil moisture conditions across a heterogeneous boreal catchment using terrain indices Hydrology and Earth System Sciences DOI 10.5194/hess-26-4837-2022 19 December 2022 Terrain indices constitute a good candidate for modelling the spatial variation of soil moisture conditions in many landscapes. In this study, we evaluate nine terrain indices on varying DEM resolution and user-defined thresholds with validation using an extensive field soil moisture class inventory. We demonstrate the importance of field validation for selecting the appropriate DEM resolution and user-defined thresholds and that failing to do so can result in ambiguous and incorrect results. Read more
GC Insights: Diversifying the geosciences in higher education: a manifesto for change Geoscience Communication DOI 10.5194/gc-5-275-2022 16 December 2022 In this manifesto, we offer six points of reflection that higher education geoscience educators can act upon to recognise and unlearn their biases and diversify the geosciences in higher education, complementing current calls for institutional and organisational change. This serves as a starting point to gather momentum to establish community-built opportunities for implementing and strengthening diversity, equity, inclusion, and justice holistically in geoscience education. Read more
Cloud adjustments from large-scale smoke–circulation interactions strongly modulate the southeastern Atlantic stratocumulus-to-cumulus transition Atmospheric Chemistry and Physics DOI 10.5194/acp-22-12113-2022 14 December 2022 Smoke from southern Africa blankets the southeast Atlantic from June-October, overlying a major transition region between overcast and scattered clouds. The smoke affects Earth’s radiation budget by absorbing sunlight and changing cloud properties. We investigate these effects in regional climate and large eddy simulation models based on international field campaigns. We find that large-scale circulation changes more strongly affect cloud transitions than smoke microphysical effects in our case. Read more
Progress and challenges in glacial lake outburst flood research (2017–2021): a research community perspective Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-3041-2022 12 December 2022 Glacial lake outburst floods (GLOFs) have attracted increased research attention recently. In this work, we review GLOF research papers published between 2017 and 2021 and complement the analysis with research community insights gained from the 2021 GLOF conference we organized. The transdisciplinary character of the conference together with broad geographical coverage allowed us to identify progress, trends and challenges in GLOF research and outline future research needs and directions. Read more
Observation-constrained estimates of the global ocean carbon sink from Earth system models Biogeosciences DOI 10.5194/bg-19-4431-2022 9 December 2022 Estimates of the ocean sink of anthropogenic carbon vary across various approaches. We show that the global ocean carbon sink can be estimated by three parameters, two of which approximate the ocean ventilation in the Southern Ocean and the North Atlantic, and one of which approximates the chemical capacity of the ocean to take up carbon. With observations of these parameters, we estimate that the global ocean carbon sink is 10% larger than previously assumed, and we cut uncertainties in half. Read more
Hydrography, circulation, and response to atmospheric forcing in the vicinity of the central Getz Ice Shelf, Amundsen Sea, Antarctica Ocean Science DOI 10.5194/os-18-1339-2022 7 December 2022 Ice shelves in the Amundsen Sea are thinning rapidly as ocean currents bring warm water into cavities beneath the floating ice. We use 2-year-long mooring records and 16-year-long model simulations to describe the hydrography and circulation near the ice front between Siple and Carney Islands. We find that temperatures here are lower than at neighbouring ice fronts and that the transport of heat toward the cavity is governed by wind stress over the Amundsen Sea continental shelf. Read more
Shallow marine carbonates as recorders of orbitally induced past climate changes – example from the Oxfordian of the Swiss Jura Mountains Climate of the Past DOI 10.5194/cp-18-2117-2022 5 December 2022 Some 155 million years ago, sediments were deposited in a shallow subtropical sea. Coral reefs formed in a warm and arid climate during high sea level, and clays were washed into the ocean at low sea level and when it rained. Climate and sea level changes were induced by cyclical insolation changes. Analysing the sedimentary record, it appears that sea level rise today (as a result of global warming) is more than 10 times faster than the fastest rise reconstructed from the geologic past. Read more
Contrasting drought legacy effects on gross primary productivity in a mixed versus pure beech forest Biogeosciences DOI 10.5194/bg-19-4315-2022 2 December 2022 Identifying drought legacy effects is challenging because they are superimposed on variability driven by climate conditions in the recovery period. We develop a residual-based approach to quantify legacies on gross primary productivity (GPP) from eddy covariance data. The GPP reduction due to legacy effects is comparable to the concurrent effects at two sites in Germany, which reveals the importance of legacy effects. Our novel methodology can be used to quantify drought legacies elsewhere. Read more
Recession or resilience? Long-range socioeconomic consequences of the 17th century volcanic eruptions in northern Fennoscandia Climate of the Past DOI 10.5194/cp-18-2077-2022 30 November 2022 Tree-ring data and written sources from northern Fennoscandia reveal that large 17th century eruptions had considerable climatic, agricultural, and socioeconomic impacts far away from the eruption locations. Yet, micro-regional investigation shows that the human consequences were commonly indirect, as various factors, like agro-ecosystems, resource availability, institutions, and personal networks, dictated how the volcanic cold pulses and related crop failures materialized on a societal level. Read more
HORAYZON v1.2: an efficient and flexible ray-tracing algorithm to compute horizon and sky view factor Geoscientific Model Development DOI 10.5194/gmd-15-6817-2022 28 November 2022 Terrain horizon and sky view factor are crucial quantities for many geoscientific applications; e.g. they are used to account for effects of terrain on surface radiation in climate and land surface models. Because typical terrain horizon algorithms are inefficient for high-resolution (< 30 m) elevation data, we developed a new algorithm based on a ray-tracing library. A comparison with two conventional methods revealed both its high performance and its accuracy for complex terrain. Read more
Reliability of flood marks and practical relevance for flood hazard assessment in southwestern Germany Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-2963-2022 25 November 2022 Encouraging a systematic use of flood marks for more comprehensive flood risk management, we collected a large number of marks along the Kinzig, southwestern Germany, and tested them for plausibility and temporal continuance. Despite uncertainty, the marks appeared to be an overall consistent and practical source that may also increase flood risk awareness. A wide agreement between the current flood hazard maps and the collected flood marks moreover indicated a robust local hazard assessment. Read more
South American Summer Monsoon variability over the last millennium in paleoclimate records and isotope-enabled climate models Climate of the Past DOI 10.5194/cp-18-2045-2022 23 November 2022 We evaluated the South American Summer Monsoon over the last millennium and dynamically interpreted the principal modes of variability. We find the spatial patterns of the monsoon are an intrinsic feature of the climate modulated by external forcings. Multi-centennial mean state departures during the Medieval Climate Anomaly and Little Ice Age show regionally coherent patterns of hydroclimatic change in both a multi-archive network of oxygen isotope records and isotope-enabled climate models. Read more
Ice core evidence for major volcanic eruptions at the onset of Dansgaard–Oeschger warming events Climate of the Past DOI 10.5194/cp-18-2021-2022 21 November 2022 Major volcanic eruptions are known to cause considerable short-term impacts on the global climate. Their influence on long-term climate variability and regime shifts is less well-understood. Here we show that very large, bipolar eruptions occurred more frequently than expected by chance just before abrupt climate change events in the last glacial period (Dansgaard–Oeschger events). Thus, such large eruptions may in some cases act as short-term triggers for abrupt regime shifts of the climate. Read more
Comprehensive space–time hydrometeorological simulations for estimating very rare floods at multiple sites in a large river basin Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-2891-2022 18 November 2022 Estimating the magnitude of rare to very rare floods is a challenging task due to a lack of sufficiently long observations. The challenge is even greater in large river basins, where precipitation patterns and amounts differ considerably between individual events and floods from different parts of the basin coincide. We show that a hydrometeorological model chain can provide plausible estimates in this setting and can thus inform flood risk and safety assessments for critical infrastructure. Read more
Bayesian assessment of chlorofluorocarbon (CFC), hydrochlorofluorocarbon (HCFC) and halon banks suggest large reservoirs still present in old equipment Atmospheric Chemistry and Physics DOI 10.5194/acp-22-11125-2022 16 November 2022 Halocarbons contained in equipment continue to be emitted after production has ceased. These “banks” must be carefully accounted for in evaluating compliance with the Montreal Protocol. We extend a Bayesian model to the suite of regulated chemicals subject to banking. We find that banks are substantially larger than previous estimates, and we identify banks by chemical and equipment type whose future emissions will contribute to global warming and delay ozone-hole recovery if left unrecovered. Read more
The impact of climate oscillations on the surface energy budget over the Greenland Ice Sheet in a changing climate The Cryosphere DOI 10.5194/tc-16-3375-2022 14 November 2022 To overcome internal climate variability, this study uses k-means clustering to combine NAO, GBI and IWV over the Greenland Ice Sheet (GrIS) and names the approach as the North Atlantic influence on Greenland (NAG). With the support of a polar-adapted RCM, spatio-temporal changes on SEB components within NAG phases are investigated. We report atmospheric warming and moistening across all NAG phases as well as large-scale and regional-scale contributions to GrIS mass loss and their interactions. Read more
Invited perspectives: Views of 350 natural hazard community members on key challenges in natural hazards research and the Sustainable Development Goals Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-2771-2022 11 November 2022 Here we present survey responses of 350 natural hazard community members to key challenges in natural hazards research and step changes to achieve the Sustainable Development Goals. Challenges identified range from technical (e.g. model development, early warning) to governance (e.g. co-production with community members). Step changes needed are equally broad; however, the majority of answers showed a need for wider stakeholder engagement, increased risk management and interdisciplinary work. Read more
Effects of orbital forcing, greenhouse gases and ice sheets on Saharan greening in past and future multi-millennia Climate of the Past DOI 10.5194/cp-18-1897-2022 9 November 2022 Using an Earth system model of intermediate complexity, we quantify contributions of the Earth’s orbit, greenhouse gases (GHGs) and ice sheets to the strength of Saharan greening during late Quaternary African humid periods (AHPs). Orbital forcing is found as the dominant factor, having a critical threshold and accounting for most of the changes in the vegetation response. However, results suggest that GHGs may influence the orbital threshold and thus may play a pivotal role for future AHPs. Read more
TermPicks: a century of Greenland glacier terminus data for use in scientific and machine learning applications The Cryosphere DOI 10.5194/tc-16-3215-2022 7 November 2022 Terminus traces have been used to understand how Greenland’s glaciers have changed over time; however, manual digitization is time-intensive, and a lack of coordination leads to duplication of efforts. We have compiled a dataset of over 39 000 terminus traces for 278 glaciers for scientific and machine learning applications. We also provide an overview of an updated version of the Google Earth Engine Digitization Tool (GEEDiT), which has been developed specifically for the Greenland Ice Sheet. Read more
Bedrock depth influences spatial patterns of summer baseflow, temperature and flow disconnection for mountainous headwater streams Hydrology and Earth System Sciences DOI 10.5194/hess-26-3989-2022 4 November 2022 The geologic structure of mountain watersheds may control how groundwater and streamwater exchange, influencing where streams dry. We measured bedrock depth at 191 locations along eight headwater streams paired with stream temperature records, baseflow separation and observations of channel dewatering. The data indicated a prevalence of shallow bedrock generally less than 3 m depth, and local variation in that depth can drive stream dewatering but also influence stream baseflow supply. Read more
Quantifying methane emissions from the global scale down to point sources using satellite observations of atmospheric methane Atmospheric Chemistry and Physics DOI 10.5194/acp-22-9617-2022 2 November 2022 We review the capability of satellite observations of atmospheric methane to quantify methane emissions on all scales. We cover retrieval methods, precision requirements, inverse methods for inferring emissions, source detection thresholds, and observations of system completeness. We show that current instruments already enable quantification of regional and national emissions including contributions from large point sources. Coverage and resolution will increase significantly in coming years. Read more
MOLISENS: MObile LIdar SENsor System to exploit the potential of small industrial lidar devices for geoscientific applications Geoscientific Instrumentation, Methods and Data Systems DOI 10.5194/gi-11-247-2022 31 October 2022 We propose a newly developed modular MObile LIdar SENsor System (MOLISENS) to enable new applications for small industrial light detection and ranging (lidar) sensors. MOLISENS supports both monitoring of dynamic processes and mobile mapping applications. The mobile mapping application of MOLISENS has been tested under various conditions, and results are shown from two surveys in the Lurgrotte cave system in Austria and a glacier cave in Longyearbreen on Svalbard. Read more
Trends in the tropospheric general circulation from 1979 to 2022 Weather and Climate Dynamics DOI 10.5194/wcd-3-777-2022 28 October 2022 This study of changes in temperature and wind since 1979 met its twin aims of (i) increasing confidence in some findings of the latest IPCC assessment and (ii) identifying changes that had received little or no previous attention. It reports a small overall intensification and shift in position of the North Atlantic jet stream and associated storms, and a strengthening of tropical upper-level easterlies. Increases in low-level winds over tropical and southern hemispheric oceans are confirmed. Read more
Soil carbon loss in warmed subarctic grasslands is rapid and restricted to topsoil Biogeosciences DOI 10.5194/bg-19-3381-2022 26 October 2022 In subarctic grassland on a geothermal warming gradient, we found large reductions in topsoil carbon stocks, with carbon stocks linearly declining with warming intensity. Most importantly, however, we observed that soil carbon stocks stabilised within 5 years of warming and remained unaffected by warming thereafter, even after > 50 years of warming. Moreover, in contrast to the large topsoil carbon losses, subsoil carbon stocks remained unaffected after > 50 years of soil warming. Read more
Root-mean-square error (RMSE) or mean absolute error (MAE): when to use them or not Geoscientific Model Development DOI 10.5194/gmd-15-5481-2022 24 October 2022 The task of evaluating competing models is fundamental to science. Models are evaluated based on an objective function, the choice of which ultimately influences what scientists learn from their observations. The mean absolute error (MAE) and root-mean-squared error (RMSE) are two such functions. Both are widely used, yet there remains enduring confusion over their use. This article reviews the theoretical justification behind their usage, as well as alternatives for when they are not suitable. Read more
The eWaterCycle platform for open and FAIR hydrological collaboration Geoscientific Model Development DOI 10.5194/gmd-15-5371-2022 21 October 2022 With the eWaterCycle platform, we are providing the hydrological community with a platform to conduct their research that is fully compatible with the principles of both open science and FAIR science. The eWatercyle platform gives easy access to well-known hydrological models, big datasets and example experiments. Using eWaterCycle hydrologists can easily compare the results from different models, couple models and do more complex hydrological computational research. Read more
Towards a self-sufficient mobile broadband seismological recording system for year-round operation in Antarctica Geoscientific Instrumentation, Methods and Data Systems DOI 10.5194/gi-11-235-2022 19 October 2022 We present a mobile and self-sufficient seismometer station concept for operation in polar regions. The energy supply can be adapted as required using the modular cascading of battery boxes, wind generators, solar cells, or backup batteries, which enables optimum use of limited resources. Our system concept is not limited to the applications using seismological stations. It is a suitable system for managing the power supply of all types of self-sufficient measuring systems in polar regions. Read more
A probabilistic framework for quantifying the role of anthropogenic climate change in marine-terminating glacier retreats The Cryosphere DOI 10.5194/tc-16-2725-2022 17 October 2022 Marine-terminating glaciers have recently retreated dramatically, but the role of anthropogenic forcing remains uncertain. We use idealized model simulations to develop a framework for assessing the probability of rapid retreat in the context of natural climate variability. Our analyses show that century-scale anthropogenic trends can substantially increase the probability of retreats. This provides a roadmap for future work to formally assess the role of human activity in recent glacier change. Read more
Stable water isotope signals in tropical ice clouds in the West African monsoon simulated with a regional convection-permitting model Atmospheric Chemistry and Physics DOI 10.5194/acp-22-8863-2022 14 October 2022 The Earth’s water cycle contains the common H2O molecule but also the less abundant, heavier HDO. We use their different physical properties to study tropical ice clouds in model simulations of the West African monsoon. Isotope signals reveal different processes through which ice clouds form and decay in deep-convective and widespread cirrus. Previously observed variations in upper-tropospheric vapour isotopes are explained by microphysical processes in convective updraughts and downdraughts. Read more
Technical note: Conservative storage of water vapour – practical in situ sampling of stable isotopes in tree stems Hydrology and Earth System Sciences DOI 10.5194/hess-26-3573-2022 12 October 2022 We developed a method of sampling and storing water vapour for isotope analysis, allowing us to infer plant water uptake depth. Measurements can be made at high temporal and spatial resolution even in remote areas. We ensured that all necessary components are easily available, making this method cost efficient and simple to implement. We found our method to perform well in the lab and in the field, enabling it to become a tool for everyone aiming to resolve questions regarding the water cycle. Read more
The Great Lakes Runoff Intercomparison Project Phase 4: the Great Lakes (GRIP-GL) Hydrology and Earth System Sciences DOI 10.5194/hess-26-3537-2022 10 October 2022 Model intercomparison studies are carried out to test various models and compare the quality of their outputs over the same domain. In this study, 13 diverse model setups using the same input data are evaluated over the Great Lakes region. Various model outputs – such as streamflow, evaporation, soil moisture, and amount of snow on the ground – are compared using standardized methods and metrics. The basin-wise model outputs and observations are made available through an interactive website. Read more
Stratigraphic templates for ice core records of the past 1.5 Myr Climate of the Past DOI 10.5194/cp-18-1563-2022 7 October 2022 Projects are underway to drill ice cores in Antarctica reaching 1.5 Myr back in time. Dating such cores will be challenging. One method is to match records from the new core against datasets from existing marine sediment cores. Here we explore the options for doing this and assess how well the ice and marine records match over the existing 800 000-year time period. We are able to recommend a strategy for using marine data to place an age scale on the new ice cores. Read more
A physical concept in the press: the case of the jet stream Geoscience Communication DOI 10.5194/gc-5-177-2022 5 October 2022 In this paper, we discuss the instrumental role of the press in informing and educating the public on the subject of climate science and climate change. We illustrate this using an example of a dissemination format called Weather Stories, published daily in one of the most read newspapers in Spain. The particularities of this journalistic format are described using a practical example of a relatively complex physical concept: the jet stream. Read more
Clouds drive differences in future surface melt over the Antarctic ice shelves The Cryosphere DOI 10.5194/tc-16-2655-2022 3 October 2022 Model projections suggest large differences in future Antarctic surface melting even for similar greenhouse gas scenarios and warming rates. We show that clouds containing a larger amount of liquid water lead to stronger melt. As surface melt can trigger the collapse of the ice shelves (the safety band of the Antarctic Ice Sheet), clouds could be a major source of uncertainties in projections of sea level rise. Read more
A tectonic-rules-based mantle reference frame since 1 billion years ago – implications for supercontinent cycles and plate–mantle system evolution Solid Earth DOI 10.5194/se-13-1127-2022 30 September 2022 We have built a community model for the evolution of the Earth’s plate–mantle system. Created with open-source software and an open-access plate model, it covers the last billion years, including the formation, breakup, and dispersal of two supercontinents, as well as the creation and destruction of numerous ocean basins. The model allows us to “see” into the Earth in 4D and helps us unravel the connections between surface tectonics and the “beating heart” of the Earth, its convecting mantle. Read more
Black carbon aerosol reductions during COVID-19 confinement quantified by aircraft measurements over Europe Atmospheric Chemistry and Physics DOI 10.5194/acp-22-8683-2022 28 September 2022 The abrupt reduction in human activities during the first COVID-19 lockdown created unprecedented atmospheric conditions. We took the opportunity to quantify changes in black carbon (BC) as a major anthropogenic air pollutant. Therefore, we measured BC on board a research aircraft over Europe during the lockdown and compared the results to measurements from 2017. With model simulations we account for different weather conditions and find a lockdown-related decrease in BC of 41 %. Read more
Impact of freshwater runoff from the southwest Greenland Ice Sheet on fjord productivity since the late 19th century The Cryosphere DOI 10.5194/tc-16-2471-2022 26 September 2022 One of the questions facing the cryosphere community today is how increasing runoff from the Greenland Ice Sheet impacts marine ecosystems. To address this, long-term data are essential. Here, we present multi-site records of fjord productivity for SW Greenland back to the 19th century. We show a link between historical freshwater runoff and productivity, which is strongest in the inner fjord – influenced by marine-terminating glaciers – where productivity has increased since the late 1990s. Read more
Towards automatic finite-element methods for geodynamics via Firedrake Geoscientific Model Development DOI 10.5194/gmd-15-5127-2022 23 September 2022 Firedrake is a state-of-the-art system that automatically generates highly optimised code for simulating finite-element (FE) problems in geophysical fluid dynamics. It creates a separation of concerns between employing the FE method and implementing it. Here, we demonstrate the applicability and benefits of Firedrake for simulating geodynamical flows, with a focus on the slow creeping motion of Earth’s mantle over geological timescales, which is ultimately the engine driving our dynamic Earth. Read more
The 852/3 CE Mount Churchill eruption: examining the potential climatic and societal impacts and the timing of the Medieval Climate Anomaly in the North Atlantic region Climate of the Past DOI 10.5194/cp-18-1475-2022 21 September 2022 We assess the climatic and societal impact of the 852/3 CE Alaska Mount Churchill eruption using environmental reconstructions, historical records and climate simulations. The eruption is associated with significant Northern Hemisphere summer cooling, despite having only a moderate sulfate-based climate forcing potential; however, evidence of a widespread societal response is lacking. We discuss the difficulties of confirming volcanic impacts of a single eruption even when it is precisely dated. Read more
Lessons from the 2018–2019 European droughts: a collective need for unifying drought risk management Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-2201-2022 19 September 2022 Recent drought events caused enormous damage in Europe. We therefore questioned the existence and effect of current drought management strategies on the actual impacts and how drought is perceived by relevant stakeholders. Over 700 participants from 28 European countries provided insights into drought hazard and impact perception and current management strategies. The study concludes with an urgent need to collectively combat drought risk via a European macro-level drought governance approach. Read more
Effects of climate change in European croplands and grasslands: productivity, greenhouse gas balance and soil carbon storage Biogeosciences DOI 10.5194/bg-19-3021-2022 16 September 2022 Crop and grassland production indicates a strong reduction due to the shortening of the length of the growing cycle associated with rising temperatures. Greenhouse gas emissions will increase exponentially over the century, often exceeding the CO2 accumulation of agro-ecosystems. Water demand will double in the next few decades, whereas the benefits in terms of yield will not fill the gap of C losses due to climate perturbation. Climate change will have a regionally distributed effect in the EU. Read more
The Sun’s role in decadal climate predictability in the North Atlantic Atmospheric Chemistry and Physics DOI 10.5194/acp-22-7893-2022 14 September 2022 Solar irradiance varies with a period of approximately 11 years. Using a unique large chemistry-climate model dataset, we investigate the solar surface signal in the North Atlantic and European region and find that it changes over time, depending on the strength of the solar cycle. For the first time, we estimate the potential predictability associated with including realistic solar forcing in a model. These results may improve seasonal to decadal predictions of European climate. Read more
Data-driven automated predictions of the avalanche danger level for dry-snow conditions in Switzerland Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-2031-2022 12 September 2022 A fully data-driven approach to predicting the danger level for dry-snow avalanche conditions in Switzerland was developed. Two classifiers were trained using a large database of meteorological data, snow cover simulations, and danger levels. The models performed well throughout the Swiss Alps, reaching a performance similar to the current experience-based avalanche forecasts. This approach shows the potential to be a valuable supplementary decision support tool for assessing avalanche hazard. Read more
Morphological controls on surface runoff: an interpretation of steady-state energy patterns, maximum power states and dissipation regimes within a thermodynamic framework Hydrology and Earth System Sciences DOI 10.5194/hess-26-3125-2022 9 September 2022 In hydrology the formation of landform patterns is of special interest as changing forcings of the natural systems, such as climate or land use, will change these structures. In our study we developed a thermodynamic framework for surface runoff on hill slopes and highlight the differences of energy conversion patterns on two related spatial and temporal scales. The results indicate that surface runoff on hill slopes approaches a maximum power state. Read more
Agricultural intensification vs. climate change: what drives long-term changes in sediment load? Hydrology and Earth System Sciences DOI 10.5194/hess-26-3021-2022 7 September 2022 This study explored the quantitative contribution of agricultural intensification and climate change to the sediment load of a small agricultural watershed. Rather than a change in climatic conditions, changes in the land structure notably altered sediment concentrations under high-flow conditions, thereby contributing most to the increase in annual sediment loads. More consideration of land structure improvement is required when combating the transfer of soil from land to water. Read more
Climate bifurcations in a Schwarzschild equation model of the Arctic atmosphere Nonlinear Processes in Geophysics DOI 10.5194/npg-29-219-2022 5 September 2022 Climate change is causing rapid temperature increases in the polar regions. A fundamental question is whether these temperature increases are reversible. If we control carbon dioxide emissions, will the temperatures revert or will we have passed a tipping point beyond which return to the present state is impossible? Our mathematical model of the Arctic climate indicates that under present emissions the Arctic climate will change irreversibly to a warm climate before the end of the century. Read more
The influence of vegetation water dynamics on the ASCAT backscatter–incidence angle relationship in the Amazon Hydrology and Earth System Sciences DOI 10.5194/hess-26-2997-2022 2 September 2022 This study investigates spatial and temporal patterns in the incidence angle dependence of backscatter from the ASCAT C-band scatterometer and relates those to precipitation, humidity, and radiation data and GRACE equivalent water thickness in ecoregions in the Amazon. The results show that the ASCAT data record offers a unique perspective on vegetation water dynamics exhibiting sensitivity to moisture availability and demand and phenological change at interannual, seasonal, and diurnal scales. Read more
Effects of rotation and topography on internal solitary waves governed by the rotating Gardner equation Nonlinear Processes in Geophysics DOI 10.5194/npg-29-207-2022 31 August 2022 Internal solitons are an important class of nonlinear waves commonly observed in coastal oceans. Their propagation is affected by the Earth’s rotation and the variation in the water depth. We consider an interplay of these factors using the corresponding extension of the Gardner equation. This model allows a limiting soliton amplitude and the corresponding increase in wavelength, making the effects of rotation and topography on a shoaling wave especially significant. Read more