ON THE ROLE OF THE 9.6 MU-M O-3 BAND IN THE ENERGETICS OF THE MESOSPHERE AND LOWER THERMOSPHERE

Radiative cooling and heating in the 9.6 mum 03 band has been calculat ed for the 50-105 km region, The NLTE effects due to the excitation of the ozone nu3 vibrations by atmospheric and solar radiation and by th e release of chemical energy into vibrations upon recombination of 0+0 2 into 03 have been taken into account. It is shown that the LTE appro ximation is good for altitudes below 70 km where fundamental transitio ns comprise the main contribution to the cooling rate. Above 70 km, th e contribution of the hot transitions to radiative cooling may exceed the contribution of the fundamental ones. In the presence of chemical excitation, part of the chemical energy radiates in the hot transition s, resulting in an additional cooling rate of about 0.5 K/day at 90 km . A method of parameterizing radiative heating which is based on the s eparation of the effects of fundamental and hot transitions in the 9.6 mum 03 band is proposed.