Mg. Mlynczak et al., Solar energy deposition rates in the mesosphere derived from airglow measurements: Implications for the ozone model deficit problem, J GEO RES-A, 105(D13), 2000, pp. 17527-17538
We derive rates of energy deposition in the mesosphere due to the absorptio
n of solar ultraviolet radiation by ozone. The rates are derived directly f
rom measurements of the 1.27-mu m oxygen dayglow emission, independent of k
nowledge of the ozone abundance, the ozone absorption cross sections, and t
he ultraviolet solar irradiance in the ozone Hartley band. Fifty-six months
of airglow data taken between 1982 and 1986 by the near-infrared spectrome
ter on the Solar-Mesosphere Explorer satellite are analyzed. The energy dep
osition rates exhibit altitude-dependent annual and semi-annual variations.
We also find a positive correlation between temperatures and energy deposi
tion rates near 90 km at low latitudes. This correlation is largely due to
the semiannual oscillation in temperature and ozone and is consistent with
model calculations. There is also a suggestion of possible tidal enhancemen
t of this correlation based on recent theoretical and observational analyse
s. The airglow-derived rates of energy deposition are then compared with th
ose computed by multidimensional numerical models. The observed and modeled
deposition rates typically agree to within 20%. This agreement in energy d
eposition rates implies the same agreement exists between measured and mode
led ozone volume mixing ratios in the mesosphere. Only in the upper mesosph
ere at midlatitudes during winter do we derive energy deposition rates (and
hence ozone mixing ratios) consistently and significantly larger than the
model calculations. This result is contrary to previous studies that have s
hown a large model deficit in the ozone abundance throughout the mesosphere
. The climatology of solar energy deposition and heating presented in this
paper is available to the community at the Middle Atmosphere Energy Budget
Project web site at http://heat-budget.gats-inc.com.