Introduction
Water vapor plays a major role in atmospheric processes
ranging from global climate change to micrometeorology. The
distribution of water vapor is highly variable in space and time.
Atmospheric scientists use surface, balloon-borne, and remote
sensing instruments to measure water vapor. Measurement of
surface water vapor is of limited use because of its high spatial
variability.
Radiosonde observations provide water vapor profiles.
Their cost limits the spacing of release sites and restricts use to
typically two daily launches per site. Thus, spatial and temporal
resolution of water vapor from radiosondes is inadequate
[Anthes, 1983], and limitations of water vapor data are a major
source of error in short-term (