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Thaw lakes and drained thaw lake basins are ubiquitous on the Arctic Coastal Plain of Alaska. Basins are wet depositional environments, ideally suited for the accumulation and preservation of organic material. Much of this soil organic carbon (SOC) is currently sequestered in the near-surface permafrost but, under a warming scenario, could become mobilized. The relative age of 77 basins on the Barrow Peninsula was estimated using the degree of plant community succession and verified by radiocarbon-dating material collected from the base of the organic layer in 21 basins. Using Landsat-7+ imagery of the region, a neural network classifying algorithm was developed from basin age-dependent spectra and texture. About 22% of the region is covered by 592 lakes (>1 ha), and at least 50% of the land surface is covered by 558 drained lake basins. Analysis of cores collected from basins indicates that (1) organic layer thickness and the degree of organic matter decomposition generally increases with basin ...

Net primary productivity (NPP) is a fundamental ecological variable that provides information about the health and status of vegetation communities. The Normalized Difference Vegetation Index, or NDVI, derived from the Advanced Very High Resolution Radiometer (AVHRR) is increasingly being used to model or predict NPP, especially over large remote areas. In this article, seven seasonally based metrics calculated from a seven-year baseline NDVI dataset were used to model NPP over Alaska, USA. For each growing season, they included maximum, mean and summed NDVI, total days, product of total days and maximum NDVI, an integral estimate of NDVI and a summed product of NDVI and solar radiation. Field (plot) derived NPP estimates were assigned to 18 land cover classes from an Alaskan statewide land cover database. Linear relationships between NPP and each NDVI metric were analysed at four scales: plot, 1-km, 10-km and 20-km pixels. Results show moderate to poor relationship between any of the metrics and NPP esti...

A group of ice‐cored frost mounds formed during the winter of 1995–1996 near Barrow, Alaska in a drained thaw‐lake basin. Over 20 mounds, ranging from 5 to 20 m across, were observed in mid‐August ...