While the effects of a mortgage-led credit crisis may be waning, the long-terms effects of a U.S. recession are just beginning, according to remarks delivered Monday by JPMorgan Chase & Co. (JPM) chief Jamie Dimon. Dimon said that he expects the U.S. to run through a recessionary phase similar to that of the early 1980s. That recession began in July 1981, and was at the time the worst recession since the Great Depression — a position that the current crisis and subsequent economic downturn seems determined to assume. In the 80s-era recession, unemployment soared to 10.8 percent in December 1982—higher than at any time in post-war era. Unemployment today stands at roughly 5 percent. Dimon suggested that economic contraction could persist through 2010, and if so, said that JPMorgan’s consumer lending business would be likely to post increasing losses tied not to bad investments, but instead to macroeconomic losses. Via Reuters:

If that happens, Dimon warned that New York-based JPMorgan and its national consumer lending businesses would suffer some significant losses, such as home equity losses doubling to $900 million by year-end. Dimon further warned that the bank would have to continue boosting loan-loss reserves if economic conditions deteriorate, further eating into profit. In the current quarter, Dimon said subprime mortgage losses could rise to between $200 million and $250 million, with prime mortgages generating about $100 million in losses.

Disclosure: The author held no positions in JPM when this story was originally published. HW reporters and writers follow a strict disclosure policy, the first in the mortgage trade.