Humidity-temperature relationships in the tropical troposphere

Abstract

Based on the observed interannual variations of water vapor and temperature over the past 26 years the authors have examined the relationship between the variations of water vapor and temperature in the tropical troposphere. The authors find that in both the lower and upper troposphere, tropical mean specific humidity increases with temperature. The rate of fractional increase of specific humidity with temperature at 500 mb is as large as that in the surface boundary layer. The authors have further compared the spatial structure of the specific humidity variations with that of the temperature variations. Though the vertical structure of tropical mean specific humidity has more variability than that of the tropical mean temperature, the leading EOF for the normalized specific humidity variations is almost exactly the same as the leading EOF for the normalized temperature variations. -from Authors