Analysis of an extreme weather event in a hyper-arid region using WRF-Hydro coupling, station, and satellite data Natural Hazards and Earth System Sciences DOI 10.5194/nhess-19-1129-2019 13 June 2019 The work addresses the need for reliable precipitation forecasts in hyper-arid environments through state-of-the-art hydro-meteorological modeling. Accounting for land–atmosphere interactions in the applied model is shown to improve the accuracy of precipitation output. The chain of events controlling the soil moisture–precipitation feedback are diagnosed and verified by in situ observations and satellite data. Read more
Global distribution of methane emissions, emission trends, and OH concentrations and trends inferred from an inversion of GOSAT satellite data for 2010–2015 Atmospheric Chemistry and Physics DOI 10.5194/acp-19-7859-2019 12 June 2019 We use 2010–2015 satellite observations of atmospheric methane to improve estimates of methane emissions and their trends, as well as the concentration and trend of tropospheric OH (hydroxyl radical, methane’s main sink). We find overestimates of Chinese coal and Middle East oil/gas emissions in the prior estimate. The 2010–2015 growth in methane is attributed to an increase in emissions from India, China, and areas with large tropical wetlands. The contribution from OH is small in comparison. Read more
Responses of an abyssal meiobenthic community to short-term burial with crushed nodule particles in the south-east Pacific Biogeosciences DOI 10.5194/bg-16-2329-2019 6 June 2019 To elucidate the potential effects of crushed nodule particle deposition on abyssal meiobenthos, we covered abyssal soft sediment in the Peru Basin (4200 m depth) with approximately 2 cm of this nodule material for 11 d. About half of the meiobenthos migrated from the sediment into the added material, and nematode feeding type proportions in that added layer were altered. These results considerably contribute to our understanding of the short-term responses of deep-sea meiobenthos to burial. Read more
Aerosol size distributions during the Atmospheric Tomography Mission (ATom): methods, uncertainties, and data products Atmospheric Measurement Techniques DOI 10.5194/amt-12-3081-2019 6 June 2019 From 2016 to 2018 a NASA aircraft profiled the atmosphere from 180 m to ~12 km from the Arctic to the Antarctic over both the Pacific and Atlantic oceans. This program, ATom, sought to sample atmospheric chemical composition to compare with global climate models. We describe the how measurements of particulate matter were made during ATom, and show that the instrument performance was excellent. Data from this project can be used with confidence to evaluate models and compare with satellites. Read more
The Bortoluzzi Mud Volcano (Ionian Sea, Italy) and its potential for tracking the seismic cycle of active faults Solid Earth DOI 10.5194/se-10-741-2019 4 June 2019 The Ionian Sea in southern Italy is at the center of active convergence between the Eurasian and African plates, with many known Mw > 7.0 earthquakes. Here, a recently discovered mud volcano (called the Bortoluzzi Mud Volcano or BMV) was surveyed during the Seismofaults 2017 cruise (May 2017). The BMV is the active emergence of crustal fluids probably squeezed up during the seismic cycle. As such, the BMV may potentially be used to track the seismic cycle of active faults. Read more
Glacial CO2 decrease and deep-water deoxygenation by iron fertilization from glaciogenic dust Climate of the Past DOI 10.5194/cp-15-981-2019 4 June 2019 Proxy records of glacial oxygen change provide constraints on the contribution of the biological pump to glacial CO2 decrease. Here, we report our numerical simulation which successfully reproduces records of glacial oxygen changes and shows the significance of iron supply from glaciogenic dust. Our model simulations clarify that the enhanced efficiency of the biological pump is responsible for glacial CO2 decline of more than 30 ppm and approximately half of deep-ocean deoxygenation. Read more
Telling the boiling frog what he needs to know: why climate change risks should be plotted as probability over time Geoscience Communication DOI 10.5194/gc-2-95-2019 29 May 2019 Humanity’s situation with respect to climate change is sometimes likened to that of a frog in a slow-boiling pot of water. But are we telling the frog what he needs to know? Most climate science is communicated to governments in the form of predictions of what is most likely to happen. I argue it should instead answer the following questions: what is the worst that could happen, and how likely will that become as time goes by? The risks and need to act will then become much clearer to see. Read more
Impacts of Three Gorges Dam’s operation on spatial–temporal patterns of tide–river dynamics in the Yangtze River estuary, China Ocean Science DOI 10.5194/os-15-583-2019 28 May 2019 In this study, we assessed the impacts of the world’s largest dam, the Three Gorges Dam (TGD), on tide–river dynamics and concluded that the strongest impacts occurred during autumn and winter due to the TGD’s operation. The results obtained will hopefully enhance our understanding of the impacts of large-scale human interventions on estuarine hydrodynamics and guide effective and sustainable water management in the Yangtze River estuary and other estuaries with substantial freshwater discharge. Read more
Recrystallization processes, microstructure and crystallographic preferred orientation evolution in polycrystalline ice during high-temperature simple shear The Cryosphere DOI 10.5194/tc-13-1495-2019 27 May 2019 Ice mechanics is an important tool to better predict the response of glaciers or polar ice sheets to climate variations. Nevertheless our current predictive abilities are limited as the microscale mechanisms responsible for ice creep are poorly identified. We show in this study, using state-of-the-art experimental techniques, which recrystallization processes control ice deformation. This will allow realistic simulations, necessary to predict the long-term effects on ice landmasses. Read more
Photooxidants from brown carbon and other chromophores in illuminated particle extracts Atmospheric Chemistry and Physics DOI 10.5194/acp-19-6579-2019 17 May 2019 We measured hydroxyl radical (•OH), singlet oxygen (1O2*), and organic triplets (3C*) in illuminated aqueous particle extracts. After measuring the impact of dilution on oxidant concentrations, we extrapolated our results to predict them in ambient particles –1O2* and3C* concentrations appear to be greatly enhanced, while•OH appears largely unchanged. Two of these oxidants (1O2*,3C*) are not yet included in atmospheric models, and our results make it possible to include them in the future. Read more
