Ground Temperature Studies in the Natural Ice-rich Permafrost Observatory (NIRPO), Prudhoe Bay region, Alaska (Data from the 2021-2024 Field Seasons)

Near-surface ground temperatures are increasing across the Arctic in response to rapidly rising air temperatures. Small changes in mean annual ground temperature (MAGT) can threaten the thermal state of permafrost, transforming landscapes through increased thermokarst and surface water hydrology, resulting in changes to snow distribution, soil moisture, vegetation, soil carbon, and greenhouse-gas fluxes.
As part of a Navigating the New Arctic project studying landscape evolution in ice-rich permafrost systems in the Prudhoe Bay region, we analyzed data from 161 temperature loggers deployed at 59 plots representing 17 common vegetation types along a soil-moisture gradient from dry tundra to aquatic forbs and mosses. The analysis indicates an overall positive trend of mean annual ground temperatures along the gradient from dry to aquatic vegetation habitats, despite some seasonal variation in this pattern.
Soil temperatures beneath aquatic vegetation plots are much warmer in winter yet slightly cooler in summer compared with dry tundra. This trend appears to hold across most major vegetation habitat types within four site moisture categories: dry, moist, wet, and aquatic. Because Arctic winters are long and soils remain frozen for most of the year, MAGT are primarily driven by winter trends.