Ni. Shiklomanov et Fe. Nelson, Analytic representation of the active layer thickness field, Kuparuk RiverBasin, Alaska, ECOL MODEL, 123(2-3), 1999, pp. 105-125
The initial response of permafrost to global warming could be an increase i
n active-layer thickness. Given that such changes could have severe consequ
ences for human infrastructure and ecosystem stability, it is important to
obtain information about spatial variations of the active layer correspondi
ng to current climatic conditions, and to determine the magnitude of possib
le near-surface permafrost degradation associated with climatic change. Sim
ple analytical solutions for frost and thaw penetration depth have long bee
n available, but were used primarily for practical applications at point lo
cations in cold-region engineering. One of these methods, developed at Mosc
ow State University by Kudryavtsev and co-workers, was used to develop a sp
atially distributed analytic model that estimates the maximum annual depth
of thaw. Kudryavtsev's procedures account for the effects of snow cover, ve
getation, soil moisture, thermal properties, and regional climate, and prov
ide estimates of surface temperature and active-layer thickness. GIS techni
ques were used to incorporate climate records, digital cartographic product
s, and field data into a spatially distributed estimate of active-layer thi
ckness. Procedures were applied over a rectangular 22 300 km(2) area in nor
th-central Alaska containing complex patterns of topography, vegetation, an
d soils. Validation procedures indicate that the Kudrayavtsev solution, ada
pted for spatial applications, yields accuracy and spatial resolution compa
rable to an existing semi-empirical method. The simplicity and low data req
uirements of the Kudryavtsev solution make it readily adaptable to differen
t geographic scales and areas. The method has potential applications in cli
mate-change studies. (C) 1999 Elsevier Science B.V. All rights reserved.