Prof. Fred Singer (“The Sea Is Rising, but Not Because of Climate Change,” op-ed, May 16) is right: CO 2 emissions have no detectable effect on sea-level rise. Profs. Andrea L. Dutton and Michael E. Mann (May 22 letter) claim, without measurable evidence, that human-caused climate change raises sea levels.
Sea-level is rising in some places and falling in others. Globally, sea levels are very slowly rising, but “human-caused climate change” cannot be the cause, because the rate of rise is no greater now than when the first Model A rolled off Ford’s assembly line.
Since precise measurements began, mean atmospheric CO 2level has risen for 58 consecutive years, with no detectable acceleration of sea-level rise. Clearly, human-caused warming doesn’t significantly increase the rate of sea-level rise.
Profs. Dutton and Mann also suppose the Antarctic ice sheet simply must lose ice in a warming climate because of “basic physics.” That’s also nonsense. Most of Antarctica averages far below freezing, so a few degrees of warming won’t melt it. Melting decreases ice-sheet mass balance, while snowfall adds to it, offsetting sea-level rise. Multiple studies confirm accumulating snow on ice sheets increases as the climate warms, the result of downwind “ocean effect snowfall.”
Compelling evidence shows global warming from fossil-fuel use is modest and benign, and higher CO 2 levels measurably benefit agriculture and natural ecosystems, outweighing hypothetical harms.
NASA meteorologist (Ret.)