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Introduction Russia's natural resource-rich and lightly populated Arctic region boasts more than its share of the country's GDP, and climate change may determine the area's future economic expansion and urban [...]

Soviet policy for settling the Russian North led to extensive in-migration in the 1960s-1980s, resulting in massive population growth and a staggering pace of urbanization in the Soviet Arctic. Multistory houses, road networks, and other infrastructure were built, transforming pristine tundra into anthropogenic and urban landscapes. The Soviet emphasis on developing Russia's Arctic regions, despite the cost and difficulty of doing so, has left a problematic legacy for modern Russia. One of the common problems shared by many Soviet-era urban communities is the debilitated state of infrastructure built on permafrost. This article provides a brief overview of the challenges associated with urban development in permafrost regions in an attempt to identify major causes of present-day infrastructure problems in the communities of the Russian North. [ABSTRACT FROM AUTHOR]

AbstractIncreases in air temperature have occurred in most parts of the Arctic in recent decades. Corresponding changes in permafrost and the active layer have resulted in decreases in ground-bearing capacity, which may not have been anticipated at the time of construction in permafrost regions. Permafrost model was coupled with empirically derived solutions adopted from Soviet and Russian construction standards and regulations to estimate the bearing capacity of foundations under rapidly changing climatic conditions, in a variety of geographic and geologic settings. Changes in bearing capacity over the last 40 years were computed for large population and industrial centers within different physiographic and climatic conditions of the Russian Arctic. The largest decreases were found in city of Nadym, where the bearing capacity has decreased by more than 40%. A smaller, but considerable decrease of approximately 20% was estimated for Yakutsk and Salekhard. Spatial model results at a regional scale depict diverse patterns of changes in permafrost-bearing capacity in Northwest Siberia and the North Slope of Alaska. The most pronounced decreases in bearing capacity (more than 20%) are estimated for the southern part of permafrost zone where deformations of engineering structures can potentially be attributed to climate-induced permafrost warming.

The n-factor, or ratio of the seasonal degree-day sum at the soil surface to that in the air at standard screen height, has been used for more than 40 yr in engineering studies to parameterize the temperature regime at the ground surface. Conceptually, this index represents the complex energy balance at the surface as a single dimensionless number and has applications in ecology, climatology, and geocryology. Although the n-factor has been used theoretically to represent the thermal regime of undisturbed natural surfaces, lack of empirical data has hindered its widespread implementation. Nine ground and one air temperature series (1995–97) from each of ten 1-ha plots on the coastal plain and Brooks Range foothills of north-central Alaska were converted to thawing (summer) n-factors and analyzed to address within- and between-plot spatial and temporal variability. Although substantial microscale variation exists, n-factors corresponding to natural vegetation/soil classes are discernable. Incorporation of n-factor values in a standard solution for the depth of thaw resulted in significantly improved estimates of active-layer thickness throughout the study area. The n-factor has considerable potential for addressing problems involving near-surface climate dynamics over extensive regions and long time periods.