, Derry, New Hampshire  July 13, 2012  Why is a 98.6-degree day
so miserable?  By Katy Waldman  — A record-dissolving heat wave
continues its sweep across the country this week, sending anyone
concerned about climate change into literal and figurative
sweats.  At least 52 deaths have been blamed on the heat.
Temperatures in New York climbed to 99 degrees Fahrenheit last
weekend. If the human body is about 98.6 degrees, why are
equivalent outdoor temperatures so uncomfortable, even
dangerous?  Because our bodies need to disperse heat, and they
can't do that effectively when the air temperature is close to
our body temperature. Our muscles and metabolism generate heat
continuously. We transfer that heat into our surroundings by
sweating, exhaling warm air and circulating blood near the
surface of our skin to cool. When the temperature gradient (or
difference) between the body and the air is high, heat flows
easily from us into the environment, and we cool down. But when
the weather hovers around our internal te