Abstract
We use ICESat-2 laser altimetry crossovers and repeat tracks collected
over the North Slope of Alaska to estimate elevation changes due to the
deformation of seasonally freezing and thawing permafrost. We compare
these measurements with a time series of surface deformation from
Sentinel-1 interferometric synthetic aperture radar (InSAR) and
demonstrate agreement between these independent observations of surface
deformation. Both methods resolve pronounced surface subsidence during
the 2019 thaw season within the 2007 Anaktuvuk River fire scar. A
temporal relationship between measured surface subsidence/uplift and
changes in normalized annual degree days is observed, consistent with
the thermodynamically driven seasonal freezing and thawing of the active
layer. We discuss optimal strategies of post-processing ICESat-2 data
for permafrost applications, as well as the future potential of joint
ICESat-2 and InSAR investigations of permafrost surface dynamics.