The first version of the Pan-European Indoor Radon Map Natural Hazards and Earth System Sciences DOI 10.5194/nhess-19-2451-2019 15 November 2019 The first version of the Pan-European Indoor Radon Map is presented in this article. The map has been developed using summary statistics estimated from 1.2 million samples. It represents an average radon concentration per 10 km x 10 km grid cell under the assumption that there are dwellings in the grid cell. It is a major contribution to the understanding of the exposure to ionizing radiation of Europeans and a first step towards a European radon exposure and, in the future, radon dose map. Read more
Seismic location and tracking of snow avalanches and slush flows on Mt. Fuji, Japan Earth Surface Dynamics DOI 10.5194/esurf-7-989-2019 15 November 2019 Avalanches and slush flows from Mt. Fuji are a major natural hazard as they may attain run-out distances of up to 4 km and destroy parts of the forest and infrastructure. We located and tracked them for the first time using seismic data. Numerical simulations were conducted to assess the precision of the seismic tracking. We also inferred dynamical properties characterizing these hazardous mass movements. This information is indispensable for assessing avalanche risk in the Mt. Fuji region. Read more
Calving cycle of the Brunt Ice Shelf, Antarctica, driven by changes in ice shelf geometry The Cryosphere DOI 10.5194/tc-13-2771-2019 15 November 2019 Two large icebergs are about to break off from the Brunt Ice Shelf in Antarctica. Rifting started several years ago and is now approaching its final phase. Satellite data and computer simulations show that over the past 2 decades, growth of the ice shelf has caused a build-up of forces within the ice, which culminated in its fracture. These natural changes in geometry coincided with large variations in flow speed, a process that is thought to be relevant for all Antarctic ice shelf margins. Read more
Effects of land use and anthropogenic aerosol emissions in the Roman Empire Climate of the Past DOI 10.5194/cp-15-1885-2019 8 November 2019 Using the global aerosol–climate model ECHAM-HAM-SALSA, the effect of humans on European climate in the Roman Empire was quantified. Both land use and novel estimates of anthropogenic aerosol emissions were considered. We conducted simulations with fixed sea-surface temperatures to gain a first impression about the anthropogenic impact. While land use effects induced a regional warming for one of the reconstructions, aerosol emissions led to a cooling associated with aerosol–cloud interactions. Read more
Electron pairing in mirror modes: surpassing the quasi-linear limit Annales Geophysicae DOI 10.5194/angeo-37-971-2019 8 November 2019 The mirror mode starts as a zero-frequency ion fluid instability and saturates quasi-linearly at very low magnetic level, while forming extended magnetic bubbles. These trap the adiabatically bouncing electron component which forms pairs near the mirror points. The large pair anisotropy causes further growth beyond quasilinear level. Including pressure equilibrium gives and estimate of the required pair density. Read more
Microbial community composition and abundance after millennia of submarine permafrost warming Biogeosciences DOI 10.5194/bg-16-3941-2019 8 November 2019 Permafrost temperatures increased substantially at a global scale, potentially altering microbial assemblages involved in carbon mobilization before permafrost thaws. We used Arctic Shelf submarine permafrost as a natural laboratory to investigate the microbial response to long-term permafrost warming. Our work shows that millennia after permafrost warming by > 10 °C, microbial community composition and population size reflect the paleoenvironment rather than a direct effect through warming. Read more
The biophysics, ecology, and biogeochemistry of functionally diverse, vertically and horizontally heterogeneous ecosystems: the Ecosystem Demography model, version 2.2 – Part 1: Model description Geoscientific Model Development DOI 10.5194/gmd-12-4309-2019 8 November 2019 Our paper describes the Ecosystem Demography model. This computer program calculates how plants and ground exchange heat, water, and carbon with the air, and how plants grow, reproduce and die in different climates. Most models simplify forests to an average big tree. We consider that tall, deep-rooted trees get more light and water than small plants, and that some plants can with shade and drought. This diversity helps us to better explain how plants live and interact with the atmosphere. Read more
The biophysics, ecology, and biogeochemistry of functionally diverse, vertically and horizontally heterogeneous ecosystems: the Ecosystem Demography model, version 2.2 – Part 2: Model evaluation for tropical South America Geoscientific Model Development DOI 10.5194/gmd-12-4347-2019 29 October 2019 The Ecosystem Demography model calculates the fluxes of heat, water, and carbon between plants and ground and the air, and the life cycle of plants in different climates. To test if our calculations were reasonable, we compared our results with field and satellite measurements. Our model predicts well the extent of the Amazon forest, how much light forests absorb, and how much water forests release to the air. However, it must improve the tree growth rates and how fast dead plants decompose. Read more
Modeling forest plantations for carbon uptake with the LPJmL dynamic global vegetation model Earth System Dynamics DOI 10.5194/esd-10-617-2019 29 October 2019 We developed a computer model that simulates forests plantations at global scale and how fast such forests can take up CO2from the atmosphere. Using this new model, we performed simulations for a scenario in which a large fraction (14 %) of global croplands and pastures are either converted to planted forests or natural forests. We find that planted forests take up CO2substantially faster than natural forests and are therefore a viable strategy for reducing climate change. Read more
Contrasting thinning patterns between lake- and land-terminating glaciers in the Bhutanese Himalaya The Cryosphere DOI 10.5194/tc-13-2733-2019 29 October 2019 We investigate thickness change of Bhutanese glaciers during 2004–2011 using repeat GPS surveys and satellite-based observations. The thinning rate of Lugge Glacier (LG) is > 3 times that of Thorthormi Glacier (TG). Numerical simulations of ice dynamics and surface mass balance (SMB) demonstrate that the rapid thinning of LG is driven by both negative SMB and dynamic thinning, while the thinning of TG is minimised by a longitudinally compressive flow regime. Read more