Towards hybrid modeling of the global hydrological cycle Hydrology and Earth System Sciences DOI 10.5194/hess-26-1579-2022 15 June 2022 We present a physics-aware machine learning model of the global hydrological cycle. As the model uses neural networks under the hood, the simulations of the water cycle are learned from data, and yet they are informed and constrained by physical knowledge. The simulated patterns lie within the range of existing hydrological models and are plausible. The hybrid modeling approach has the potential to tackle key environmental questions from a novel perspective. Read more
Evaporation enhancement drives the European water-budget deficit during multi-year droughts Hydrology and Earth System Sciences DOI 10.5194/hess-26-1527-2022 13 June 2022 Droughts are a creeping disaster, meaning that their onset, duration and recovery are challenging to monitor and forecast. Here, we provide further evidence of an additional challenge of droughts, i.e. the fact that the deficit in water supply during droughts is generally much more than expected based on the observed decline in precipitation. At a European scale we explain this with enhanced evapotranspiration, sustained by higher atmospheric demand for moisture during such dry periods. Read more
Performance of temperature and productivity proxies based on long-chain alkane-1, mid-chain diols at test: a 5-year sediment trap record from the Mauritanian upwelling Biogeosciences DOI 10.5194/bg-19-1587-2022 10 June 2022 A 5-year record of long-chain mid-chain diol export flux and composition is presented with a 1- to 3-week resolution sediment trap CBeu (in the NW African upwelling). All environmental parameters as well as the diol composition are dominated by the seasonal cycle, albeit with different phase relations for temperature and upwelling. Most diol-based proxies are dominated by upwelling. The long-chain diol index reflects temperatures of the oligotrophic summer sea surface. Read more
101 geodynamic modelling: how to design, interpret, and communicate numerical studies of the solid Earth Solid Earth DOI 10.5194/se-13-583-2022 8 June 2022 Geodynamic modelling of the solid Earth provides a powerful tool to investigate processes in the Earth’s crust and mantle that are not directly observable. In this review, we present a comprehensive yet concise overview of the modelling process with an emphasis on best practices, clear communication, and synergies with related fields. Hence, this review is the perfect starting point for anyone wishing to (re)gain a solid understanding of geodynamic modelling as a whole. Read more
Magnitude, frequency and climate forcing of global volcanism during the last glacial period as seen in Greenland and Antarctic ice cores Climate of the Past DOI 10.5194/cp-18-485-2022 6 June 2022 We employ acidity records from Greenland and Antarctic ice cores to estimate the emission strength, frequency and climatic forcing for large volcanic eruptions from the last half of the last glacial period. A total of 25 volcanic eruptions are found to be larger than any eruption in the last 2500 years, and we identify more eruptions than obtained from geological evidence. Towards the end of the glacial period, there is a notable increase in volcanic activity observed for Greenland. Read more
A predictive viscosity model for aqueous electrolytes and mixed organic–inorganic aerosol phases Atmospheric Chemistry and Physics DOI 10.5194/acp-22-3203-2022 3 June 2022 Depending on temperature and chemical makeup, certain aerosols can be highly viscous or glassy, with atmospheric implications. We have therefore implemented two major upgrades to the predictive viscosity model AIOMFAC-VISC. First, we created a new viscosity model for aqueous electrolyte solutions containing an arbitrary number of ion species. Second, we integrated the electrolyte model within the existing AIOMFAC-VISC framework to enable viscosity predictions for organic–inorganic mixtures. Read more
Persistence of moist plumes from overshooting convection in the Asian monsoon anticyclone Atmospheric Chemistry and Physics DOI 10.5194/acp-22-3169-2022 1 June 2022 The Asian monsoon anticyclone is the key contributor to the global annual maximum in lower stratospheric water vapour. We investigate the impact of deep convection on the lower stratospheric water using a unique set of observations aboard the high-altitude M55-Geophysica aircraft deployed in Nepal in summer 2017 within the EU StratoClim project. We find that convective plumes of wet air can persist within the Asian anticyclone for weeks, thereby enhancing the occurrence of high-level clouds. Read more
Ideas and perspectives: Sea-level change, anaerobic methane oxidation, and the glacial–interglacial phosphorus cycle Biogeosciences DOI 10.5194/bg-19-1421-2022 30 May 2022 A glacial–interglacial methane-fuelled redistribution of reactive phosphorus between the oceanic and sedimentary phosphorus reservoirs can occur in the ocean when falling sea level lowers the pressure on the seafloor, destabilizes methane hydrates, and triggers the dissolution of P-bearing iron oxides. The mass of phosphate potentially mobilizable from the sediment is similar to the size of the current oceanic reservoir. Hence, this process may play a major role in the marine phosphorus cycle. Read more
Bacterial and eukaryotic intact polar lipids point to in situ production as a key source of labile organic matter in hadal surface sediment of the Atacama Trench Biogeosciences DOI 10.5194/bg-19-1395-2022 27 May 2022 In this study, we investigate the chemical diversity and abundance of microbial lipids as markers of organic matter sources in the deepest points of the Atacama Trench sediments and compare them to similar lipid stocks in shallower surface sediments and in the overlying water column. We evaluate possible organic matter provenance and some potential chemical adaptations of the in situ microbial community to the extreme conditions of high hydrostatic pressure in hadal realm. Read more
The impact of stratospheric aerosol intervention on the North Atlantic and Quasi-Biennial Oscillations in the Geoengineering Model Intercomparison Project (GeoMIP) G6sulfur experiment Atmospheric Chemistry and Physics DOI 10.5194/acp-22-2999-2022 25 May 2022 Simulations by six Earth-system models of geoengineering by introducing sulfuric acid aerosols into the tropical stratosphere are compared. A robust impact on the northern wintertime North Atlantic Oscillation is found, exacerbating precipitation reduction over parts of southern Europe. In contrast, the models show no consistency with regard to impacts on the Quasi-Biennial Oscillation, although results do indicate a risk that the oscillation could become locked into a permanent westerly phase. Read more
