Integrating ICESat-2 altimetry, optical imagery, and digital elevation models to measure erosion rates and coastal morphology along the Alaskan Beaufort Sea Coast
Abstract
Arctic coastlines are rapidly retreating due to declining sea ice extent, increasing storm frequency and intensity, permafrost thaw, and increasing air and sea surface temperatures. Coastline erosion and retreat poses a threat to infrastructure and cultural sites, and it leads to the release of carbon and other previously bound compounds into the ocean and atmosphere. Understanding the controls on long- and short-term coastline response to changing climate forcings is vital in forecasting future vulnerability. Previous work has considered the relationship between variations in erosion rates and coastal morphology, but with limited temporal sampling. Satellite imagery can provide estimates of erosion rates and land type at high spatial and temporal resolution, but provides limited information on vertical changes in coastal morphology. Airborne elevation surveys can provide high-resolution measurements of the vertical structure of coastal regions, but are costly and limited in their spatial and temporal coverage.
With a 91-day revisit time and dense along-track sampling, the satellite laser altimeter ICESat-2 provides an opportunity to regularly measure coastal position and vertical structure on seasonal to annual timescales. This project proposes a framework for processing and interpreting ICESat-2 elevation profiles over Arctic coastal regions, starting with a case study of multiple near-coincident ICESat-2 profiles on the Alaskan Beaufort Sea Coast spanning 2019-2021 that capture distinct morphological features. We leverage ICESat-2-derived observations in tandem with satellite optical imagery and available elevation datasets to illustrate the evolution of coastal features over multiple open-water seasons and situate these changes in the context of historical measurements. We consider spatial variations in the coastline response to observed sea ice, wind and wave conditions, and evaluate to what extent these variations correspond to different morphological settings. We will discuss the potential for this multi-sensor approach to be applied on a regional scale to help improve our understanding of the role of morphologic setting in modulating Arctic coastal erosion rates.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.C35A..02B