Abstract

Evidence derived from the carefully screened temperature record at Eau Claire, Mich., and from radiosonde data at Sault Ste. Marie, Mich., supports the conclusion of Wahl and Lawson that a return to the temperature and circulation features of the early and mid-19th century in the eastern United States may be underway. Cooling trends at Eau Claire during the most recent decades have been accompanied by progressive lowering of the 700-mb surface at Sault Ste. Marie, and increased cold air advection into the southern Great Lakes area.

PDF