Maritime Arctic 831 Characteristics

The major characteristics of the maritime Arctic are extensive cloudiness, high humidity and a small range in annual temperature. Such climatic conditions are best developed in the Atlantic sector of the Arctic, such as at Jan Mayen (Svalbard) and Iceland. On Jan Mayen the mean temperature is near -7 °C in February and 7 °C in August. There is fairly ample precipitation in all months with an autumn maximum (Wilson 1969). Nome in western Alaska is another example of a maritime site, but in this case reflecting Pacific influences. It has an almost identical precipitation regime but higher totals. Here the mean monthly relative humidity is between 76 and 82%.

Boulder Rainfall Annual
Figure 8.5 Mean annual cycles of surface air temperature, precipitation, cloud cover and downwelling shortwave radiation for Resolute Bay, NWT, based on a number of different data sources (courtesy of M. Lavrakas, NSIDC, Boulder, CO).

Some investigators cite areas such as the Bering Strait and the coasts of the Beaufort and Chukchi seas as having maritime climates although winter temperatures are much lower. Climatic conditions for Barrow, Alaska, have been discussed extensively (e.g., Moritz, 1979; Dingman et al., 1980). During the snow-free season along such coastal areas, there is often a rapid increase of temperatures inland. This is seen clearly in the July mean field of surface air temperature (Figure 2.20). Recall from Chapter 4 that this coastal temperature gradient extends through a considerable depth of the lower troposphere and defines the summer Arctic frontal zones.

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