- All lakes visually inspected show signs of rapid expansion up to 1 m/yr

- Extensive permafrost collapse areas on lake margins are camouflaged by floating
vegetation mats (FVM); collapse zones expand with more than 1 m/yr

- Low shorelines towards old basins appear to erode more rapid than high bluffs ! impact of
ice content and sediment volume that has to be removed

- Some considerably large lakes drained partially or completely

- Very few new lakes formed

- Direct impact of long-term precipitation fluctuations on water level appears to be negligible
compared to thermokarst and erosion dynamics; however, short-term precipitation events
might be a cause for activating or speeding up both erosion and drainage processes


- Only lakes in Yedoma deposits around Cherskii were assessed so far

- Human disturbance results in massive thermokarst

- Erosion rates are similar to Seward Peninsula


• A wide range of high-resolution remote sensing platforms are available today for Arctic Research

• Remote sensing is highly valuable to assess the spatial dimensions of environmental change in the Arctic

• Using remote sensing we can cover 42 years of land surface changes in the Kolyma lowland and 56 years on the Seward Peninsula

• Thermokarst is highly dynamic and active today in Siberia and Alaska – probably we will see surprising results and feedbacks in the coming years

• Thermokarst lakes behave nonlinear in their spatial dynamics; driven by cryolithological ground conditions and external forcing, slow lake forming processes are accompanied by phases of rapid expansion or sudden drainage