Langley DAAC Version Number:   LD_008_027_003_00_00_0_19990614



Contrail-Cirrus Studies at FARS; Ken Sassen - University of Utah

In support of all NASA SUCCESS aircraft missions into the vicinity of the DOE
Southern Great Plains CART site (36.605 degrees N, 97.488 degrees W) near
Lamont, OK, ground-based remote sensing measurements were collected by a mobile
remote sensing platform from the University of Utah, including the
dual-wavelength scanning Polarization Diversity Lidar (PDL), coaligned
midinfrared radiometer and video recorder, and all-sky video and 35-mm
photography.  Additional data were obtained at other times during periods of
cirrus cloudiness and from extensive fields of contrails generated by local
commercial jet aircraft.  A radar-based laser safety shutdown device for
automatic aircraft identification was successfully tested using a variety of
aircraft, allowing PDL scans of cirrus and contrails to be made for the first
time.  Exceptionally high resolution PDL data were also obtained at 1.5-m range
and 0.1-s time resolutions, revealing a surprising amount of fine scale
structures in cirrus clouds and contrails.  A preliminary inspection of our
SUCCESS dataset reveals that although portions of contrails created by the
participating NASA aircraft were sampled, the extensive fields of contrails from
nearby commercial jet corridors, including subvisual sheets of spreading
contrails, were the most notable and extensively studied.