Variability of active-layer thickness at multiple spatial scales, north-central Alaska, USA

To examine the scales at which the maximum variability of active-layer thic kness occurs within local areas, a nested sampling and analysis design was implemented in five 1-km(2) areas distributed over two physiographic provin ces in north-central Alaska. The primary variations of thaw depth in the lo w-relief terrain of the Arctic Coastal Plain province occur over distances between 100 and 300 m, and are superimposed on a trend related to the regio nal climatic gradient. in the Arctic Foothills province, much of the variat ion within the study areas occurs over horizontal distances less than 3 m, and is superimposed on mesoscale variations induced by terrain climate. To achieve maximum effectiveness, research programs concerned with sampling, i nterpolating, or modeling thaw depth and closely related phenomena should b e designed to accommodate substantial variability at multiple spatial scale s.