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A humid continental climate (Köppen prefix ''D'' and a third letter of ''a'' or ''b'') is a climatic region defined by Russian German climatologist Wladimir Köppen in 1900, which is typified by large seasonal temperature differences, with warm to hot (and often humid) summers and cold (sometimes severely cold) winters. Precipitation is usually well distributed through the year. The definition of this climate regarding temperature is as follows: the mean temperature of the coldest month must be below and there must be at least four months whose mean temperatures are at or above . In addition, the location in question must not be semi-arid or arid. Humid continental climates tend to be found between latitudes 30° N and 60° N, within the central and northeastern portions of North America, Europe, and Asia. They are much less commonly found in the Southern Hemisphere due to the larger ocean area at that latitude and the consequent greater maritime moderation. In the Northern Hemisphere some of the humid continental climates, typically in Scandinavia, Nova Scotia, and Newfoundland are heavily maritime-influenced, with relatively cool summers and winters being just below the freezing mark.〔(【引用サイトリンク】title=Halifax, Nova Scotia Temperature Averages )〕 More extreme humid continental climates found in southern Siberia and the American Midwest combine hotter summer maxima and colder winters than the marine-based variety. In some areas there are both strong subtropical and subarctic air mass influences depending on season, like the humid and hot summers and the frigid winters of Milwaukee, Wisconsin〔(【引用サイトリンク】title=Milwaukee, Wisconsin Temperature Averages )〕 in the Upper Midwest of the United States. ==Definition== Climatological averages are used to determine which locations are within a certain climate regime. The World Meteorological Organization has defined this average as through a 30 year period. The version from 1936 utilized a mean temperature of the coldest month of below and there must be at least four months whose mean temperatures are at or above . These temperatures were not arbitrary. In Europe, the average temperature isotherm (line of equal temperature) was near the southern extent of winter snowpack. The average temperature was found to be the minimum temperature necessary for tree growth. Large temperature ranges are common within this climate zone. In addition, the location in question must not be semi-arid or arid. Many climatologists in the U.S. prefer to use as the standard because they feel it better reflects consistency in regional landscapes. This is from an update to the climate regime definition introduced by Trewartha & Horn in 1980. Despite the 1980 update, climate regimes are essentially the same within the Southern Hemisphere. The largest changes are seen in North America, Europe, and northern Asia.〔 Under Köppen, the following variants of this climate are possible. The climate regime uses a three letter code, beginning with the letter ''D''. Otherwise,〔(【引用サイトリンク】title=Updated world map of China and Japan, and Syria, the Köppen-Geiger climate classification )〕 * The second letter * * ''f'' : Does not meet either of the alternative specifications. * * ''s'' : A dry summer — the driest summer month has at most of rainfall and has at most the precipitation of the wettest winter month. * * ''w'' : A dry winter — the driest winter month has at most one‑tenth of the precipitation found in the wettest summer month. * The third letter * * ''a'' : Warmest month averages above * * ''b'' : Does not meet the requirements for ''a'', but there still are at least four months above . 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Humid continental climate」の詳細全文を読む スポンサード リンク
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