What is the average precipitation in polar region

In general, the annual precipitation is high over oceans and over the windward part of adjoining continents. The importance of high ground e. Rocky Mountains, southern Greenland, Scotland and Norway for generating orographic precipitation is also clear from this map. The distribution of precipitation in the Arctic represents a complex problem, subject of long-standing debate and compounded by the paucity of meteorological stations.

While air temperatures today are registered at Arctic meteorological stations with relative small technical difficulties, except for sites with icing conditions, precipitation is considerably more complicated to measure correctly, especially when in solid form.

Many Arctic meteorological stations have simply avoided measuring precipitation due to severe problems by doing so. In addition, little is known about the local and regional effect of altitude and topography on precipitation.

Also the local and regional importance of redistribution of snow by wind is usually virtually unknown Humlum ; Humlum ; Humlum et al. Finally, much of the information that does exist on precipitation within the Arctic tends to be widely scattered in the scientific literature and is often viewed only in the context of a particular local problem, with little emphasis on the regional amount of precipitation Humlum In addition, high-latitude trends in measured precipitation are influenced by gauge under catch.

At a meteorological station exposed to warming, the fraction of annual precipitation falling as snow diminishes, and vice versa. Notwithstanding all these limitations, the existing meteorological records of precipitation still provide the mean to test the association between air temperature and precipitation back in time. At the bottom of this page a series of diagrams show how precipitation and air temperatures have varied during the 20th century in regions north of 50 o N.

First, however, it is useful to see how the average 20th century precipitation has been distributed according to the existing meteorological records. This is illustrated by the three diagrams below. Click here for information on data sources, etc. Click here to jump back to the list of contents.

Distribution of the average May-October 20th century precipitation north of 50 o N, in mm w. The observation network is thin especially within the Arctic Ocean , and details of individual contour lines may well represent artifacts of interpolation, only. As May-October represents the warm season north of 50 o N, most of the precipitation will fall as rain during this period, except over the highest ground e. The east-west precipitation gradient across continents is less pronounced than shown above for the annual precipitation.

This is partly because of importance of local precipitation events over continental interiors, e. Distribution of the average November-April 20th century precipitation north of 50 o N, in mm w. As November-April represents the cold season north of 50 o N, most of the precipitation will fall as snow during this period. The east-west precipitation gradient across continents is pronounced compared to the warm season see diagram above , as most precipitation falls in connection with cyclonic activity.

Extensive Arctic regions in Canada, Alaska and Siberia are very arid dry during the cold season, and only a shallow snow cover will accumulate during the winter. By this, the ground surface has little protection towards low air temperatures and will cool rapidly.

The most extensive permafrost regions in northern hemisphere are found within these dry regions. Conversely, snow and glaciers will more easily accumulate in the mountains of Norway, compared to the mountains in Siberia. Arctic seasonal snow cover. The general problem of reliable records on Arctic precipitation has implications for our knowledge on the duration and thickness of the seasonal snow cover, significant for the ground thermal regime Ballantyne ; Humlum et al.

Snow plays a key role in protecting plants and animals from cold dry winter conditions. It is also important for the seasonal water cycle. Variations in the snow cover may therefore have profound impact on biological activity and landforming geomorphic activity in the Arctic. In addition, t he snow cover also has a direct effect on the distribution of permafrost on both local and regional scale Humlum et al.

In arid parts of the Arctic land regions the average winter snow cover is thin and the ground surface cools rapidly during the winter. Conversely, in more maritime areas the snow cover usually is thicker and reduces heat loss from the ground surface during winter see diagram below. Interannual variations in timing of the establishment of the snow cover are also important.

A dry and cold autumn enables enhanced cooling of the active layer and topmost permafrost, while high snowfall during late winter and late onset of snow melt protect the ground against thawing in early summer. The combination of these two meteorological phenomena is likely to be beneficial for conservation and growth of permafrost. Variations in the timing and duration of the seasonal snow cover presumably also have an influence on active layer thickness, but the effect is still not known in detail Humlum et al.

Average 20th century insulation factor N-factor November-April. Climate Systems and Change. Search for:. Temperature: Winters are entirely dark and bitterly cold. Summer days are long, but the sun is low on the horizon so summers are cool.

The annual temperature range is large. Precipitation: The region is dry with less than 25 cm 10 inches of precipitation annually; most precipitation occurs during the summer. Polar Tundra ET The polar tundra climate is continental, with severe winters. Licenses and Attributions. America S. East Oceania. East Oceania All the countries. Climate - Antarctica Average weather, temperature, rainfall, when to go, what to pack.

Larger than Europe, and roughly circular-shaped, this continent is nearly centerd on the South Pole and is surrounded by the three oceans of the Southern Hemisphere, namely, Atlantic, Pacific and Indian.