Last month, a Government scientist predicted that the number of days here on which the maximum tempertaure exceeds 100 degrees might just climb from one day a year, on average, to 12 days a year by the year 2050, and that the number of nights in which the temperature does not fall below 80 degrees might leap from one a year to 19.

The scientist, Dr. James E. Hansen, a climatologist at the National Aeronautics and Space Administration, describing a study of the global phenomenon of ”the greenhouse effect,” told a Senate subcommittee that such temperature changes ”may significantly affect the climactic environment for the general population.”

TURN UP THAT AIR-CONDITIONER AND READ THIS – NYTimes.com