Альберта: География и Водные Ресурсы

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Alberta is one of the thirteen provinces and territories of Canada. Located in Western Canada, the province has an area of and is bounded to the south by the United States state of Montana along 49° north for ; to the east at 110° west by the province of Saskatchewan for ; and at 60° north the Northwest Territories for The southern half of the province borders British Columbia along the Continental Divide of the Americas on the peaks of the Rocky Mountains, while the northern half borders British Columbia along the 120th meridian west. Along with Saskatchewan it is one of only two landlocked provinces or territories.

With the exception of the southern section, the province of Alberta is well watered. Rising from numerous valleys on the Alberta declivity of the Rocky Mountains between the international boundary line and 52° north are streams which unite to form the Oldman River, and farther north the Bow River. Running eastward these two rivers unite about 112° west, and flow on under the name of the South Saskatchewan River. North of 52° north many small streams unite to form the Red Deer River, which flowing southeastward joins the South Saskatchewan near 110° west. Between 52° and 53° north rises the great river, the North Saskatchewan River. It receives a southern tributary, the Battle River, which joins it about 108° west. Pursuing their courses eastward the North and South Saskatchewan rivers unite in the Saskatchewan River (, "swift flowing river"), which finds its way to Lake Winnipeg, and thence by way of Nelson River to Hudson Bay. It is one of the mightiest rivers of the continent. At Mount Athabasca, there is an unusual occurrence where the water flows either to the Pacific Ocean on the western slope, the Arctic Ocean on the northeast, and Hudson Bay on the southeast. In the northern part of the province, between 53° and 54° north, all the waters of Alberta flow toward the Arctic Ocean. Starting at Mount Athabasca, the Athabasca River runs north and empties into Lake Athabasca near 58° north. North of 56° north flows through and from the Rocky Mountains as the Peace River. After descending northeastward to within a few miles of Lake Athabasca, it is met by a stream emerging from that lake. The united river carrying down the waters of the Athabasca slope is called the Slave River, which, passing through Great Slave Lake, emerges as the great Mackenzie River, which flows into the Arctic Ocean. Alberta thus gives rise to the two great rivers, the Saskatchewan and the Mackenzie. While a number of fresh water, or in some cases brackish, lakes each less than in extent are situated in Alberta, two of more considerable size are found. These are Lake Athabasca, in extent, of which the greater part is in Saskatchewan, and the other Lesser Slave Lake in area.

As Alberta extends for approximately from north to south, it is natural that the climate should vary considerably between parallels of 49° and 60° north and also between approximately 110° and 120° west. It is also further influenced by the different altitudes found in the province. In general, Alberta's climate is dry, due to the rain shadow effect of the Rocky Mountains and Pacific Coast Ranges to the west, and continental, due to its distance from any large body of water. The contrast between warming, dry winds descending from the Rockies and proximate cold air in Yukon, however, gives Alberta (and the adjacent Mackenzie Basin) during the winter the highest variability in monthly temperatures anywhere in the world. Exceptionally warm winter months in the province can be as warm as oceanic climates at similar latitudes – for instance Edmonton averaged in February 1977 – whereas the coldest winter months like January 1950 when Edmonton averaged are comparably cold to such Siberian localities as Aldan, Sakha.

Most of Southern Alberta east of the Rockies and outside of the Cypress Hills, especially Palliser's Triangle, is a dry steppe, with most locations having an annual average precipitation of 280 430mm. Under the Köppen climate classification, most places in Southern Alberta are either semi arid (Köppen climate classification BSk), or humid continental (Köppen climate classification Dfb) (the "humid" designation denotes that these climates do not meet the criteria to be semi arid, not that they necessarily have high humidity levels). Most places in Southern Alberta that fall under the "humid continental" classification are close to the borderline between semi arid and humid continental. This region has the hottest summer temperatures in Alberta and quite cold winters, though chinook winds ameliorate the cold winter temperatures temporarily when they pass over. The natural vegetation of this region is mainly dry mixed grass prairie, grading to mixed grass prairie, and then fescue prairie as precipitation increases with higher altitude and / or latitude. This area is prone to drought and farming here is not successful without significant irrigation.