The catastrophic thermokarst lake drainage events of 2018 in northwestern Alaska: Fast-forward into the future The Cryosphere DOI 10.5194/tc-2020-106 21 May 2020 Northwestern Alaska has been highly affected by changing climatic patterns with new temperature and precipitation maxima over the recent years. In particular, the Baldwin and northern Seward peninsulas are characterized by an abundance of thermokarst lakes that are highly dynamic and prone to lake drainage, like many other regions at the southern margins of continuous permafrost. We used Sentinel-1 synthetic aperture radar (SAR) and Planet CubeSat optical remote sensing data to analyze recently observed widespread lake drainage. Read more
Quantification of seasonal and diurnal dynamics of subglacial channels using seismic observations on an Alpine glacier The Cryosphere DOI 10.5194/tc-14-1475-2020 19 May 2020 Our study addresses key questions on the subglacial drainage system physics through a novel observational approach that overcomes traditional limitations. We conducted, over 2 years, measurements of the subglacial water-flow-induced seismic noise and of glacier basal sliding speeds. We then inverted for the subglacial channel’s hydraulic pressure gradient and hydraulic radius and investigated the links between the equilibrium state of subglacial channels and glacier basal sliding. Read more
Summarizing the state of the terrestrial biosphere in few dimensions Biogeosciences DOI 10.5194/bg-17-2397-2020 19 May 2020 To closely monitor the state of our planet, we require systems that can monitor the observation of many different properties at the same time. We create indicators that resemble the behavior of many different simultaneous observations. We apply the method to create indicators representing the Earth’s biosphere. The indicators show a productivity gradient and a water gradient. The resulting indicators can detect a large number of changes and extremes in the Earth system. Read more
Intercomparison of wind observations from the European Space Agency’s Aeolus satellite mission and the ALADIN Airborne Demonstrator Atmospheric Measurement Techniques DOI 10.5194/amt-13-2075-2020 14 May 2020 This work reports on the first airborne validation campaign of ESA’s Earth Explorer mission Aeolus, conducted in central Europe during the commissioning phase in November 2018. After presenting the methodology used to compare the data sets from the satellite, the airborne wind lidar and the ECWMF model, the wind results from the underflights performed are analyzed and discussed, providing a first assessment of the accuracy and precision of the preliminary Aeolus wind data. Read more
The acidity of atmospheric particles and clouds Atmospheric Chemistry and Physics DOI 10.5194/acp-20-4809-2020 14 May 2020 Acid rain is recognized for its impacts on human health and ecosystems, and programs to mitigate these effects have had implications for atmospheric acidity. Historical measurements indicate that cloud and fog droplet acidity has changed in recent decades in response to controls on emissions from human activity, while the limited trend data for suspended particles indicate acidity may be relatively constant. This review synthesizes knowledge on the acidity of atmospheric particles and clouds. Read more
Drainage divide networks – Part 2: Response to perturbations Earth Surface Dynamics DOI 10.5194/esurf-8-261-2020 12 May 2020 Drainage divides are believed to provide clues about divide migration and the instability of landscapes. Here, we present a novel approach to extract drainage divides from digital elevation models and to order them in a drainage divide network. We present our approach by studying natural and artificial landscapes generated with a landscape evolution model and disturbed to induce divide migration. Read more
The benefits to climate science of including early-career scientists asreviewers Geoscience Communication DOI 10.5194/gc-3-89-2020 12 May 2020 Early-career scientists (ECSs) are rarely invited to act as peer reviewers. Participating in a group peer review of the IPCC Special Report on Ocean and Cryosphere in a Changing Climate, PhD students spent more time reviewing than more established scientists and provided a similar proportion of substantive comments. By soliciting and including ECSs in peer review, the scientific community would reduce the burden on more established scientists and may improve the quality of that process. Read more
Brief communication: Residence time of energy in the atmosphere Nonlinear Processes in Geophysics DOI 10.5194/npg-27-235-2020 30 April 2020 We deduce that after a global thermal perturbation, the Earth’s atmosphere would need about a couple of months to come back to equilibrium. Read more
Drainage divide networks – Part 1: Identification and ordering in digital elevation models Earth Surface Dynamics DOI 10.5194/esurf-8-245-2020 30 April 2020 Drainage divides are believed to provide clues about divide migration and the instability of landscapes. Here, we present a novel approach to extract drainage divides from digital elevation models and to order them in a drainage divide network. We present our approach by studying natural and artificial landscapes generated with a landscape evolution model and disturbed to induce divide migration. Read more
Authigenic formation of Ca–Mg carbonates in the shallow alkaline LakeNeusiedl, Austria Biogeosciences DOI 10.5194/bg-17-2085-2020 29 April 2020 Dolomite (CaMg(CO 3 ) 2 ) is supersaturated in many aquatic settings (e.g., seawater) on modern Earth but does not precipitate directly from the fluid, a fact known as the dolomite problem. The widely acknowledged concept of dolomite precipitation involves microbial extracellular polymeric substances (EPSs) and anoxic conditions as important drivers. In contrast, results from Lake Neusiedl support an alternative concept of Ca–Mg carbonate precipitation under aerobic and alkaline conditions. Read more
