A mixed-methods approach to assessing sub-seasonal retreat rates of retrogressive thaw slumps in the Eureka Area, Ellesmere Island, Nunavut, Canada
Abstract
Retrogressive thaw slumps (RTSs) are dynamic, horse-shoe shaped, mass wasting features generated by the degradation of ice-rich permafrost that can remain active for many years. RTSs are composed of an ablating ice-rich headwall that generates fluidized sediment that flows downslope impacting hydrology, ecosystems, and infrastructure. Increases in RTS numbers, size and growth rates have been observed in various parts of the Arctic in recent years but typically rely on annual or decadal-scale observations. Using a combination of high resolution satellite imagery (Worldview 1, 2 and 3) and field measurements (differential GPS surveys), we assess sub-seasonal, lateral retreat rates for 12 RTSs in the Eureka area of the Canadian high Arctic during nine separate thaw seasons (2011 to 2019). The goal of our sub-seasonal analysis is to better understand the climate and terrain factors controlling RTS activity, as when only one headwall measurement is taken for annual analysis, this essentially divides each time period into two half seasons. We correlate sub-seasonal retreat rates to climate factors provided by the Eureka Weather Station and to terrain factors derived from the ArcticDEM. Our sub-seasonal analysis is then placed in the context of annual observations on lateral retreat and volume loss discerned using a dense time series of data generated by the ArcticDEM project.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMC012.0001L
- Keywords:
-
- 0708 Thermokarst;
- CRYOSPHERE;
- 0710 Periglacial processes;
- CRYOSPHERE;
- 0774 Dynamics;
- CRYOSPHERE