PermaRisk - Simulating erosion processes in permafrost landscapes under a warming climate – a risk assessment for ecosystems and infrastructure within the Arctic
Almost a quarter of the land surface of the northern hemisphere of the earth is characterized by permanently frozen soils. Strong climate warming in the Arctic leads to thawing of permafrost soils, triggering large-scale landscape and ecosystems changes and thereby severely impacting the heat and water cycles of Arctic ecosystems. At the same time, carbon and other nutrients that are stored in large amounts in permafrost soils are exposed to microbial decomposition upon thaw. By this decomposition greenhouse gases are produced in the soils which can further amplify climate warming. In addition, thawing reduces the structural stability of the soils. The resulting erosion leads to strong mass wasting (movement of soil material) which can reshape entire landscapes.
These changes threaten the stability of Arctic ecosystems as well as infrastructure that is important to Arctic's life and economy. Infrastructure such as supply roads, airports, pipelines, and fuel storages is often built directly on highly temperature-sensitive frozen ground. Offshore activities and shipping in the Arctic are also dependent on facilities in permafrost regions such as ports. The safety of this infrastructure is directly dependent on the thermal stability of the underlying and surrounding permafrost. Reliable and prompt assessments of risks of potential damages to both the ecology and infrastructure are therefore critically important.
The PermaRisk project aims to provide novel tools for the simulation of erosion and mass wasting processes in permafrost landscapes under a warming climate. Current land surface models used to simulate permafrost dynamics are not capable to represent soil erosion and mass wasting. Thus, current model assessments are most likely far too conservative in their estimates of permafrost thaw impacts. The following research questions have not yet been answered and are therefore at the focus of the project:
• How does climate warming affect the intensity of erosion and mass wasting processes?
• How does erosion and mass wasting affect infrastructure and ecosystem functions such as the energy, water, and nutrient cycles in the Arctic?
• What are the interactions between erosion-induced landscape changes and permafrost degradation?
In order to answer these crucial questions the junior researchers will extend and improve the permafrost model CryoGrid3 developed by the Alfred-Wegener-Institute in cooperation with the University of Oslo. To ensure realistic model development, they use field measurements as well as satellite data from three key research sites in Alaska, Canada, and Siberia for model validation.
Dr. Moritz Langer
Alfred Wegener Institute Helmholtz-Zentrum für Polar- und Meeresforschung (AWI)
Telegrafenberg A45, 14473 Potsdam, Germany
Tel.: +49 (0)331 288 2154