LAS experiment: evidence for direct injection of water vapor into stratosphere and stratospheric ozone depletion by HOx in the northern-hemisphere low-latitude region in April

Studied are the mechanism of water-vapor injection into the stratosphere, and the stratospheric photochemistry between ozone and water-vapor in the northern-hemisphere low-latitude region with use of the data from satellite-born infrared spectrometer LAS. A significant longitudinal ozone distribution is found at a latitude of 7°N in April 1984; the universality is confirmed. For the mechanism, hypothesized are: (1) water vapor will be directly injected into the stratosphere at the present latitude region in April, (2) water vapor will reduce the stratospheric ozone concentration by photochemical processes, (3) the slip-stream interaction between a tropospheric northerly wind and the ascending current of water vapor will cause a characteristic ozone distribution near a longitude of 90°. The hypothesis agrees well with JMA´s upper atmospheric meteorological data and the LAS water-vapor data. In particular, a clear anticorrelation is found between the water-vapor and ozone distributions in the stratosphere; the stratospheric ozone depletion by photochemical reaction with water vapor is thus confirmed, as predicted theoretically