Ice-rich permafrost is ground that is frozen all year round for two or more years and contains particularly large amounts of water that will be released upon thawing. This ice is the element of Arctic landscapes most susceptible to climate warming. Nearly 50% of the Arctic has ice-rich permafrost. For example, the upper 4-5 meters of the land along Alaska's northern coast contains an estimated 77% ice. Thawing of ice-rich permafrost affects entire arctic ecosystems and makes the ground unstable to build upon. This dataset consists of an orthomosaic and digital surface model (DSM) derived from drone surveys on 29 August 2021 at the Navigating the New Arctic, Ice-rich Permafrost Systems project field sites, in collaboration with the PermaSense project, in the Prudhoe Bay Oilfields. 2,463 digital images were acquired from a DJI Phantom 4 Real-Time Kinematic (DJI P4RTK) quadcopter with a DJI D-RTK 2 Mobile Base Station. The mapped area was around 232 hectares (ha). The drone system was flown at 100 meters (m) above ground level (agl) and flight speeds varied from 7–8 meters/second (m/s). The orientation of the camera was set to 90 degrees (i.e. looking straight down). The along-track overlap and across-track overlap of the mission were set at 80% and 70%, respectively. All images were processed in the software Pix4D Mapper (v. 4.6.4) using the standard 3D Maps workflow and the accurate geolocation and orientation calibration method to produce the orthophoto mosaic and digital surface model at spatial resolutions of 5 and 10 centimeters (cm), respectively. A Leica Viva differential global positioning system (GPS) provided ground control for the mission and the data were post-processed to WGS84 UTM Zone 6 North in Ellipsoid Heights (meters). Elevation information derived over waterbodies is noisy and does not represent the surface elevation of the feature.
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The Fate of Permafrost
Permafrost is ground that remains frozen
year-round due to a cold climate; the active layer
is the ground above the permafrost that thaws
and re-freezes each year. Nearly 40 million acres
of National Park Service (NPS) land in Alaska,
similar to the size of Florida, lie within the zone
of continuous or discontinuous permafrost.
Permafrost can be classified as continuous
(>90% of land area underlain by permafrost),
discontinuous (90%-50%), sporadic (50%-10%),
or isolated (<10%; Ferrians 1965). Permafrost
is most vulnerable to climatic warming when its
temperature is within a few degrees of thawing.
Large-scale permafrost thawing would lead to a
major reconfiguration of the landscape through
the development of thermokarst (irregular
topography resulting from ground ice melting).
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- Award ID(s):
- 1636476
- NSF-PAR ID:
- 10050056
- Date Published:
- Journal Name:
- Alaska park science
- Volume:
- 16
- Issue:
- 1
- ISSN:
- 1545-4967
- Page Range / eLocation ID:
- 37-44
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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