Polar Benthic Ecology

The Arctic is warming about twice the rate than the global average, most prominently visible in the drastic decrease of sea ice extent and thickness. We are interested how these changes affect specifically the benthic macro- and megafauna communities. By applying a biological trait approach on a pan-Arctic scale we aim to get insight in the benthic functional variability, identify the functions and regions most susceptible to change, and predict benthic eco system functioning in a future, seasonally ice-free Arctic Ocean.

Climate Monitoring and Cryosphere

Long-term monitoring data are crucial to detect ongoing trends, develop a process-based understanding, and eventually, model potential future scenarios. The currently changing climate likely enhances geohazards on global (e.g. sea level rise), regional (e.g. landslide-triggered tsunamis), and local scale (e.g. outburst floods). We are interested in the climate’s impact on the polar cryosphere for these different scales, whereas in-situ field observations are building the foundation of our research. Peripheral glaciers and ice caps in Greenland are currently a substantial contributor to sea level rise. Since 2007 we are measuring the annual mass budget of Freya glacier. Freya glacier is one of just three glaciers on the Greenland east coast exhibiting a long-term mass balance initiative. Furthermore, we are interested in understanding catastrophic events of gravitational mass movements and glacial outburst floods, and their potential relation to the prevailing climate in the polar regions.

Polar Meteorology / Ice Core Interpretation

The stable isotope ratio of polar ice is one of the crucial proxies to derive paleotemperatures. For a correct interpretation of ice core data, however, we need to fully understand the precipitation mechanisms that lead to the formation of the ice. This includes moisture sources and transport as well as meteorological conditions at the time and location of snow deposition. To investigate this we use recent stable isotope and meteorological station data combined with high-resolution atmospheric modeling. Our focus is on process studies in Antarctica.

Archaea in Arctic Soils

Nitrification, the oxidation of ammonia to nitrate, is a crucial process in arctic soils, as it influences the availability of nitrogen, a major limiting nutrient in these ecosystems. Nitrification also contributes directly and indirectly to N₂O production. We investigate the distribution and activity of distinct clades of ammonia oxidizing archaea that we found to be associated with different nitrification rates in arctic soils and we explore their contribution to nitrification in the context of the complex microbial communities found in arctic soils.