Progress in monitoring landcover and human presence in the Arctic based
on satellite data
Abstract
Landcover information is of relevance for a range of applications in
Arctic environments including up-scaling of in situ measurements,
permafrost monitoring and modelling and climate change impact
assessment. But not only natural landcover types, also the
identification of human impacted areas is required. A wide range of
satellite records are available, but often there are coverage and
resolution limitations. Due to the spatial heterogeneity typical for the
Arctic, an as high as possible spatial resolution is needed. Sentinel-1
as well as Sentinel-2 offer 10m nominal resolution for specific bands
and modes and are freely available across the entire Arctic. The
multi-spectral information from Sentinel-2 is specifically of value for
discrimination of tundra types. The Synthetic Aperture Radar mission
Sentinel-1 provides added value through representation of land surface
structure features. A combination of both allows significantly improved
characterization of landcover over larger areas. Here, we review recent
progress in monitoring the land surface close to Arctic coasts (focus
region of HORIZON2020 Nunataryuk), specifically the distribution of
human impacted areas beyond of what is represented in databases such as
OpenStreetMap or global settlement maps. The added value of machine
learning techniques will be discussed and results based on Sentinel-1
und Sentinel-2 presented. Further on, permafrost change information
provided through the ESA CCI+ Permafrost project is combined with the
novel maps. The CCI+ Permafrost datasets cover 1997-2018 for ground
temperature, active layer thickness and permafrost fraction with 1 km
gridding (partially derived from MODIS LST,
https://climate.esa.int/en/projects/permafrost/data/) and therefore
allow detailed assessment of areas with human presence over permafrost.