BOSTON, Sept. 9 (UPI) -- Extreme summertime temperatures are likely to become a regular occurrence even if expected increases in global temperatures are avoided, U.S. researchers say.
Boston University researchers, in an article in the journal Climate Change Letters, have estimated the impact increases in global-mean temperatures might have on summer temperatures in the United States and around the globe.
They based their estimate on current international efforts to limit human-induced global surface temperature increases to 2 degrees centigrade, (3.5 degrees Fahrenheit.)
"In particular, we wanted to determine if preventing the global-mean temperature increase from reaching this threshold would prevent extreme temperature values from becoming a normal occurrence in these regions," Bruce Anderson, professor of geography and environment, said.
The researchers' analysis found that even if an increase in the global mean temperature is limited to the 3.5 degree Fahrenheit target, current historical extreme values would still effectively become the norm for 70 percent to 80 percent of Earth's land surface.
The western third of the United Stated could follow Africa, Asia, and the Amazon as areas in which summertime temperature extremes will become the norm, they said.
"In these regions, if the 2 degree C threshold is passed, it is more likely than not that every summer will be an extreme summer compared with today," Anderson said.
