Unraveling biogeographical patterns and environmental drivers of soil fungal diversity at the French national scale SOIL DOI 10.5194/soil-10-251-2024 15 May 2024 The fungal kingdom has been diversifying for more than 800 million years by colonizing a large number of habitats on Earth. Based on a unique dataset (18S rDNA meta-barcoding), we described the spatial distribution of fungal diversity at the scale of France and the environmental drivers by tackling biogeographical patterns. We also explored the fungal network interactions across land uses and climate types. Read more
NEWTS1.0: Numerical model of coastal Erosion by Waves and Transgressive Scarps Geoscientific Model Development DOI 10.5194/gmd-17-3433-2024 13 May 2024 Models of rocky coastal erosion help us understand the controls on coastal morphology and evolution. In this paper, we present a simplified model of coastline erosion driven by either uniform erosion where coastline erosion is constant or wave-driven erosion where coastline erosion is a function of the wave power. This model can be used to evaluate how coastline changes reflect climate, sea-level history, material properties, and the relative influence of different erosional processes. Read more
The perfect storm? Co-occurring climate extremes in East Africa Earth System Dynamics DOI 10.5194/esd-15-429-2024 10 May 2024 Climate change affects the interaction, dependence, and joint occurrence of climate extremes. Here we investigate the joint occurrence of pairs of river floods, droughts, heatwaves, crop failures, wildfires, and tropical cyclones in East Africa under past and future climate conditions. Our results show that, across all future warming scenarios, the frequency and spatial extent of these co-occurring extremes will increase in this region, particularly in areas close to the Nile and Congo rivers. Read more
Resemblance of the global depth distribution of internal-tide generation and cold-water coral occurrences Ocean Science DOI 10.5194/os-20-569-2024 8 May 2024 Cold-water corals (CWCs) and tidal waves in the interior of the ocean have been connected in case studies. We demonstrate this connection globally using hydrodynamic simulations and a CWC database. Internal-tide generation shows a similar depth pattern with slope steepness and latitude as CWCs. Our results suggest that internal-tide generation can be a useful predictor of CWC habitat and that current CWC habitats might change following climate-change-related shoaling of internal-tide generation. Read more
Evaluating the impact of climate communication activities by scientists: what is known and necessary? Geoscience Communication DOI 10.5194/gc-7-91-2024 6 May 2024 Climate scientists are urged to communicate climate science; there is very little evidence about what types of communication work well for which audiences. We have performed a systematic literature review to analyze what is known about the efficacy of climate communication by scientists. While we have found more than 60 articles in the last 10 years about climate communication activities by scientists, only 7 of these included some form of evaluation of the impact of the activity. Read more
Dependency of the impacts of geoengineering on the stratospheric sulfur injection strategy – Part 2: How changes in the hydrological cycle depend on the injection rate and model used Earth System Dynamics DOI 10.5194/esd-15-405-2024 3 May 2024 This study is the second in a two-part series in which we explore the dependency of the impacts of stratospheric sulfur injections on both the model employed and the strategy of injection utilized. The study uncovers uncertainties associated with these techniques to cool climate, highlighting how the simulated climate impacts are dependent on both the selected model and the magnitude of the injections. We also show that estimating precipitation impacts of aerosol injection is a complex task. Read more
The six rights of how and when to test for soil C saturation SOIL DOI 10.5194/soil-10-275-2024 29 April 2024 Soil C saturation has been tested in several recent studies and led to a debate about its existence. We argue that, to test C saturation, one should pay attention to six fundamental principles: the right measures, the right units, the right dispersive energy and application, the right soil type, the right clay type, and the right saturation level. Once we take care of those six rights across studies, we find support for a maximum of C stabilized by minerals and thus soil C saturation. Read more
Interpretability of negative latent heat fluxes from eddy covariance measurements in dry conditions Biogeosciences DOI 10.5194/bg-21-2051-2024 26 April 2024 Porous materials are known to reversibly trap water from the air, even at low humidity. However, this behavior is poorly understood for soils. In this analysis, we test whether eddy covariance is able to measure the so-called adsorption of atmospheric water vapor by soils. We find that this flux occurs frequently during dry nights in a Mediterranean ecosystem, while EC detects downwardly directed vapor fluxes. These results can help to map moisture uptake globally. Read more
Carbon budget concept and its deviation through the pulse response lens Earth System Dynamics DOI 10.5194/esd-15-387-2024 22 April 2024 The carbon budget approach is based on a close linear relationship between the global temperature and cumulative emissions. This article reinterprets the carbon budget approach through the lens of the temperature response to an emission pulse in the role of a Green’s function, or as a generalization of TCRE. It shows that inspecting the simple model’s pulse response allows for a prediction of deviations for any possible emission scenario and derivation of a nonlinear carbon budget equation. Read more
Quantitative imaging of carbon dioxide plumes using a ground-based shortwave infrared spectral camera Atmospheric Measurement Techniques DOI 10.5194/amt-17-2257-2024 19 April 2024 Imaging carbon dioxide (CO2) plumes of anthropogenic sources from planes and satellites has proven valuable for detecting emitters and monitoring climate mitigation efforts. We present the first images of CO2 plumes taken with a ground-based spectral camera, observing a coal-fired power plant as a validation target. We develop a technique to find the source emission strength with an hourly resolution, which reasonably agrees with the expected emissions under favorable conditions. Read more
HydroFATE (v1): a high-resolution contaminant fate model for the global river system Geoscientific Model Development DOI 10.5194/gmd-17-2877-2024 16 April 2024 Treated and untreated wastewaters are sources of contaminants of emerging concern. HydroFATE, a new global model, estimates their concentrations in surface waters, identifying streams that are most at risk and guiding monitoring/mitigation efforts to safeguard aquatic ecosystems and human health. Model predictions were validated against field measurements of the antibiotic sulfamethoxazole, with predicted concentrations exceeding ecological thresholds in more than 400 000 km of rivers worldwide. Read more
Rates of palaeoecological change can inform ecosystem restoration Biogeosciences DOI 10.5194/bg-21-1629-2024 12 April 2024 Rate-of-change records based on compositional data are ambiguous as they may rise irrespective of the underlying trajectory of ecosystems. We emphasize the importance of characterizing both the direction and the rate of palaeoecological changes in terms of key features of ecosystems rather than solely on community composition. Past accelerations of community transformation may document the potential of ecosystems to rapidly recover important ecological attributes and functions. Read more
Subglacial valleys preserved in the highlands of south and east Greenland record restricted ice extent during past warmer climates The Cryosphere DOI 10.5194/tc-18-1467-2024 10 April 2024 This study uses airborne radar data and satellite imagery to map mountainous topography hidden beneath the Greenland Ice Sheet. We find that the landscape records the former extent and configuration of ice masses that were restricted to areas of high topography. Computer models of ice flow indicate that valley glaciers eroded this landscape millions of years ago when local air temperatures were at least 4 °C higher than today and Greenland’s ice volume was < 10 % of that of the modern ice sheet. Read more
Minimizing the effects of Pb loss in detrital and igneous U–Pb zircon geochronology by CA-LA-ICP-MS Geochronology DOI 10.5194/gchron-6-89-2024 8 April 2024 Chemical abrasion (CA) is a technique that reduces or eliminates the effects of Pb loss in zircon U–Pb geochronology. However, CA has yet to be applied to large-n detrital zircon (DZ) analyses. We show that CA does not negatively impact or systematically bias U–Pb dates, improves the resolution of age populations defined by 206Pb/238U dates, and increases the percentage of concordant analyses in age populations defined by 207Pb/206Pb dates. Read more
Extreme melting at Greenland’s largest floating ice tongue The Cryosphere DOI 10.5194/tc-18-1333-2024 5 April 2024 The 79° North Glacier in Greenland has experienced significant changes over the last decades. Due to extreme melt rates, the ice has thinned significantly in the vicinity of the grounding line, where a large subglacial channel has formed since 2010. We attribute these changes to warm ocean currents and increased subglacial discharge from surface melt. However, basal melting has decreased since 2018, indicating colder water inflow into the cavity below the glacier. Read more
Solar radiation modification challenges decarbonization with renewable solar energy Earth System Dynamics DOI 10.5194/esd-15-307-2024 3 April 2024 Most solar radiation modification (SRM) simulations assume no physical coupling between mitigation and SRM. We analyze the impact of SRM on photovoltaic (PV) and concentrated solar power (CSP) and find that almost all regions have reduced PV and CSP potential compared to a mitigated or unmitigated scenario, especially in the middle and high latitudes. This suggests that SRM could pose challenges for meeting energy demands with solar renewable resources. Read more
Possible role of anthropogenic climate change in the record-breaking 2020 Lake Victoria levels and floods Earth System Dynamics DOI 10.5194/esd-15-225-2024 27 March 2024 Heavy rainfall in eastern Africa between late 2019 and mid 2020 caused devastating floods and landslides and drove the levels of Lake Victoria to a record-breaking maximum in May 2020. In this study, we characterize the spatial extent and impacts of the floods in the Lake Victoria basin and investigate how human-induced climate change influenced the probability and intensity of the record-breaking lake levels and flooding by applying a multi-model extreme event attribution methodology. Read more
A past and present perspective on the European summer vapor pressure deficit Climate of the Past DOI 10.5194/cp-20-573-2024 25 March 2024 The main aim of this paper is to present the summer vapor pressure deficit (VPD) reconstruction dataset for the last 400 years over Europe based on δ18O records by using a random forest approach. We provide both a spatial and a temporal long-term perspective on the past summer VPD and new insights into the relationship between summer VPD and large-scale atmospheric circulation. This is the first gridded reconstruction of the European summer VPD over the past 400 years. Read more
Distinct oxygenation modes of the Gulf of Oman over the past 43 000 years – a multi-proxy approach Biogeosciences DOI 10.5194/bg-21-1477-2024 22 March 2024 We analyse benthic foraminifera, nitrogen isotopes and lipids in a sediment core from the Gulf of Oman to investigate how the oxygen minimum zone (OMZ) and bottom water (BW) oxygenation have reacted to climatic changes since 43 ka. The OMZ and BW deoxygenation was strong during the Holocene, but the OMZ was well ventilated during the LGM period. We found an unstable mode of oscillating oxygenation states, from moderately oxygenated in cold stadials to deoxygenated in warm interstadials in MIS 3. Read more
Observations of cyanogen bromide (BrCN) in the global troposphere and their relation to polar surface O3 destruction Atmospheric Chemistry and Physics DOI 10.5194/acp-24-3421-2024 20 March 2024 We measured cyanogen bromide (BrCN) in the troposphere for the first time. BrCN is a product of the same active bromine chemistry that destroys ozone and removes mercury in polar surface environments and is a previously unrecognized sink for active Br compounds. BrCN has an apparent lifetime against heterogeneous loss in the range 1–10 d, so it serves as a cumulative marker of Br-radical chemistry. Accounting for BrCN chemistry is an important part of understanding polar Br cycling. Read more