Abstract
The most important feedback in the climate system is related to changes
in atmospheric water vapor or specific humidity (SH), with some of this
water vapor transported to the upper troposphere through thunderstorms.
This study uses lightning and SH data to show high correlations between
the zonal mean lightning activity and the zonal mean SH concentrations
in the upper troposphere. The best correlations (r~0.9)
are between lightning activity and UTWV at the 200 mb level
(~12 km altitude). Both lightning and SH at 200mb are
20% higher in July than in January. While the SH increases in
concentration above the thunderstorms in the upper troposphere, in the
lower stratosphere, a significant drying of the atmosphere is observed
due to the “cold trap” region near the tropopause where the atmosphere
is “freeze-dried” by the production of ice crystals and cirrus clouds,
preventing the further rise of water vapor into the stratosphere.