Lakes are abundant features on coastal plains of the Arctic and most are termed "thermokarst" because they form in ice-rich permafrost and gradually expand over time. The dynamic nature of thermokarst lakes also makes them prone to catastrophic drainage and abrupt conversion to wetlands, called drained thermokarst lake basins (DTLBs). Together, thermokarst lakes and DTLBs cover up to 80% of arctic lowland regions, making understanding their response to ongoing climate change essential for coastal plain environmental assessment. Datasets presented here document water level and temperature (surface and ground) regimes for a large (38 sites) array of lake with high drainage potential and lake basin (DTLBS), which have already drained, located on differing terrain units of Alaska's Arctic Coastal Plain. Lake data was measured along deep protected shorelines using pressure transducers to record hourly water level and bed temperature. Wetland (DTLB) data was also measured with pressure transducers and ground thermistors at 25 and 100 centimeters (cm) depth. Of special interest at some DTLB sites was the potential occurrence of snow-dam outburst events during the early summer snowmelt periods. In these cases, pressure transducers were set to log at 10 minute intervals for this period. All data archived here are summarized at daily average values.
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Snow depth survey in North Slope, Alaska, 2022
This is the field measured snow depth data using an automatic snow depth probe (magnaprobe, Snow-Hydro LCC) in April 19 - May 7, 2022 in North Slope, Alaska. The data are in csv format (comma delimited text format with geographical coordinate, WGS 84, and UTM zone 5).
The goal of this research project is to quantify the role of thermokarst lake drainage and drained thermokarst lake basin (DTLB) evolution in the arctic system. The joint research team (University of Alaska, Fairbanks, University of Wyoming, and Michigan Technological University) spent several days based in Utqiagvik (Western Coastal Plain) and rest of days in Teshekpuk Lake (Central Coastal Plain). During the travel, manual snow survey was conducted using the mangaprobe to quantify the snowdrift around thermokarst lakes and other land features as complementary to the geophysical and remote sensed snowpack characterizations.
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- Award ID(s):
- 1806213
- NSF-PAR ID:
- 10473688
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- ["snow depth","magnaprobe"]
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Snowdrifts formed by wind transported snow deposition represent a vital component of the earth surface processes on Arctic tundra. Snow accumulation on steep slopes particularly at the margins of rivers, coasts, lakes, and drained lake basins (DLBs) comprise a significant water storage component for the ecosystem during spring and summer snowmelt. The tundra landscape is in constant change as lakes drain, substantially altering the surface morphology that partially controls how snow drifts and accumulates throughout the cold seasons. Here, we combine field measurements, remote sensing observations, and snow modeling to investigate how lake drainage affects snow redistribution at Inigok on the Arctic Coastal Plain of Alaska, where the snow movement is controlled by wind. Field observations included measurements of snow depth using ground penetrating radar and probe. We mapped mid‐July snow cover and modeled snow redistribution before and after drainage simulation for 33 lakes (∼30 km2) in our study area (∼140 km2). Our results show the advantage of using a wide range of snow depth measurements on frozen lakes, DLBs, and upland to validate the snow modeling in order to capture the variability inherent in the landscape. The lake drainage simulation suggests an increase in snow storage of up to ∼24% at DLBs compared to extant lakes, ∼35% considering only snowdrifts (assumed as ≥1 m depth), and ∼4% considering the whole study area. This increase in snow accumulation could significantly impact the landscape when it melts, including wildlife, vegetation, biogeochemical processes, and potential natural hazards like snow‐dam outburst floods.
