6.2
Midlatitude Cirrus Cloud Structural Properties Derived From the Extended FARS Dataset
Kenneth Sassen, University of Utah, Salt Lake City, UT; and L. Wang
Current climate models treat cirrus clouds as horizontally-homogeneous, plane-parallel sheets. However, there is growing recognition that inhomogeneous cloud properties can have a large impact on the transfer of solar and terrestrial radiation, and hence on the radiation balance of the earth/atmosphere system. In this study we analyze the statistical properties of several hundred polarization `3-h lidar case studies of midlatitude cirrus clouds obtained over the past 14 y from the University of Utah Facility for Atmospheric Remote Sensing (FARS) in Salt Lake City, Utah. Variations in the lidar returns, as proxies of cloud content structures, are analyzed using wavelet transform and other approaches to characterize the basic scale-lengths of these features in cirrus clouds. In particular, we will examine the following statistics; 1) fractional cirrus cloud cover amounts for broken cirrus, 2) cloud layer overlap for multiple cirrus layers, and 3) the basic nature (i.e., dynamical process) and scale-lengths of internal cirrus structures as related to cirrus cloud type (i.e., generation mechanism) and cloud top temperature.
Session 6, Upper Troposphere Clouds
Wednesday, 5 June 2002, 10:30 AM-12:00 PM
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