The history of Columbia County, Wisconsin, containing an account of its settlement, growth, development and resources; an extensive and minute sketch of its cities, towns and villages--their improvements, industries, manufactories, churches, schools and societies; its war record, biographical sketches, portraits of prominent men and early settlers; the whole preceded by a history of Wisconsin, statistics of the state, and an abstract of its laws and constitution and of the constitution of the United States
Oldenhage, H. H.
Climatology of Wisconsin, pp. -128 PDF (3.9 MB)
CLIMATOLOGY OF WISCONSIN. The extreme summer climate of the eastern United States is owing to the southerly and southwesterly winds, which blow with great regularity during this season, and, after traversing great areas of tropical seas, bear the warmth and moisture of these seas far inland, and give this region the peculiar semi-tropical character of its summers. The average temperature of summer varies between 8o0 for the Gulf states, and 6o' for the extreme north. While in the Gulf states the thermometer often rises to ioo°', in the latitude of Wisconsin this occurs-very seldom. During winter the prevailing winds are from the northwest. These cold blasts from the Arctic sea are deflected by the Rocky mountains, sweep down unopposed into lower latitudes, and produce all the rigors of an arctic winter. The mean temperature for this season varies between 6o' for the Gulf coast and 15. for the extreme northern part of Wisconsin. In the northern part of the valley the cold is sometimes so intense that the thermometer sinks to the freezing point of mercury. The extreme of heat and cold would give a continental climate if this extreme were not accom- panied by a profusion of rain. The southerly winds, laden with m'oisture,ý distribute this moist. ure with great regularity over the valley. The amount of rainfall, greater in summer than in winter, varies, from the Gulf of Mexico to Wisconsin, from 63 inches to 30 inches. On the At. lantic coast, where the distribution is more equal throughout the year on account of its proximity to the ocean, the amount varies, from Florida to Maine, from 63 to 40 inches. The atmospheric movements on which, to a great extent, the climatic conditions of the eastern United States depend, may be summed up as follows: i. That the northeast trades, deflected in their course to south and southeast winds in their passage through the Carribean Sea and the Gulf of Mexico, are the warm and moist winds which communicate to the Mississippi valley and the Atlantic slope their fertility. "2. That the prevalence of these winds from May to October communicates to this region a sub-tropical climate. "3. That in the region bordering on the Gulf of Mexico, the atmospheric disturbances are propagated from south to north; but in the northern and middle states, owing to a prevailing upper current, from west to east. "t4. That while this upper current is cool and dry, and we have the apparent anomaly of rain storms traveling from west to east, at the same time the moisture supplying them comes from the south. "5. That, in the winter, the south and southeast winds rise into the upper current, while the west and northwest winds descend and blow as surface winds, accompanied by an extraor. dinary depression of temperature, creating, as it were, an almost arctic climate. "6. That the propagation of the cold winds from west to east is due to the existence of a warmer and lighter air to the eastward. "7. That in summer the westerly currents seldom blow with violence, because, in passing over the heated plains, they acquire nearly the same temperature as the southerly currents, but in winter the conditions are reversed.") The line of conflict of these aerial currents, produced by unequal atmospheric pressure, shift so rapidly that the greatest changes of temperature, moisture, and-wind, are experienced within a few hours, these changes usually affecting areas of great extent. In the old world, on the other hand, the momntain systems, generally running from east to west, offer an impediment, especially to the polar currents, and the weather is therefore not so changeable. Wisconsin, situated in the upper and central part of the Mississippi valley, is subject to the same general climatic conditions which give this whole area its peculiar climate. The highest mean summer temperature is 72° Fahrenheit in the southwestern part of the 123
Based on date of publication, this material is presumed to be in the public domain.| Original materal owned by South Central Library System.| For information on re-use see: http://digital.library.wisc.edu/1711.dl/Copyright