April 20 HIS CLOUD EMISSIVITY QUICKLOOK

HIS Cloud Emissivity Examples for the April 20, 1996 SUCCESS FLIGHT

This figure shows HIS brightness temperature measurements from the ER-2 altitude and their respective effective cloud emissivity spectra for the period of 1551Z to 1804Z. During this two hours period, at least four different cloud emissivities are detected. They are from very transparent thin cirrus (1551 Z) to vary opaque cold high cloud (1804 Z) shown from the HIS IR spectra covering from 650 1/cm (15.38 micron) to 1050 1/cm (9.52 micron). The derived effective cloud emissivity spectra are indicating these cloud features also. In general, cloud emissivities are varying from 0.1 to 0.95 over the longwave IR window (10 to 12.5 micron) and non-gray clouds are shown clearly with very different emissivity in the 10 and 12.5 micron regions.

If question contact Allen Huang/ allenh@ssec.wisc.edu