If global temperatures were to rise 4 degrees Celsius, how would Chicago be affected? Should I buy palm trees or sell my snowblower?
-- Eric Hansen, Lake in the Hills
Forget the palms, but you might get by without a snowblower. A temperature rise of 4 degrees Celsius (7.2 degrees Fahrenheit) roughly would increase Chicago’s average temperature to 57 degrees, comparable to cities near Illinois’ southern tip. Those cities typically receive less than 12 inches of snow compared to about 37 inches in Chicago. Winters would be milder with few, if any, subzero days and fewer than 90 days below freezing in contrast to about 130 in Chicago. Summers would be hotter, averaging more than 40 days of at least 90 degrees compared to about 20 in a typical Chicago summer.