The development of knowledge about the climate of Illinois

Adequate understanding of all aspects of the climate of Illinois and its effects on humans and the environment has required data collection and research over the past 150 years.Meaningful climate studies were limited before about 1910 by the lack of an adequate network of weather stations to provide needed surface data. The evolution of anetwork of weather stations involved three eras of development that began in 1849 and included the Smithsonian Institute, U.S. Army, and the Department of Agriculture.In-depth stud-ies of climate, given adequateupper air datathat began being collected during the 1920s-1940s, were launched after 1950 . These have defined the considerable spatial variations in climate across the state, some caused by Lake Michigan and others by the hills of southern Illinois.The studies have also shown that considerable temporal fluctuations in temperatures and precipitation have occurred since 1850, but recent data do not suggest a change in Illinois’ climate due to global warming.Studies have also defined the impacts of state’s climate on human health and well being, on agriculture, transportation, busi-ness, and the environment.