¥Increasing water vapor concentrations shift
the altitude of water IR emission upward which DECREASES its
emission (because of colder temperatures)
¥Atmospheric temperatures
have also been increasing over time (at least in theory) which should INCREASE the IR emission from water vapor
¥To isolate the water vapor concentration
change, Subtract the IR measured from water (=ÔT12Õ from
HIRS) from emission measured from O2 (whose concentrations have not changed)
(=ÔT2Õ from MSU)
¥If IR from water is becoming
less than emission from O2, the atmospheric water concentrations have increased => THIS IS WHAT IS OBSERVED