Satellite Climatology Classes

Prior to the experiment, a satellite climatology of the COARE region was performed using data for three austral summers (Mapes and Houze, 1992: Satellite-observed cloud clusters in the TOGA COARE domain. TOGA Notes, No. 7, April 1992). The purpose of this study was to understand better the spectrum of meteorological conditions to expect during the experiment itself. Cloud systems were classified according to the area of their constituent cloudiness elements (CE) with cloud-top IR black-body temperatures (TBB) < 208 K. The satellite climatology results showed that the CE population can be represented by a log-normal distribution, with median size of 20,000 km**2. For the purpose of providing guidance in flight planning, the spectrum of CE's was partioned into five classes (0-4).

Cloud Element Classes

Class 0:

no CEs with TBB<208 K over an area of roughly 20,000 km**2, (length ~100 km)

Class 1:

first quartile of CE spectrum--CEs with area < 6,000 km**2, (length ~20-30 km)

Class 2:

second quartile of CE spectrum--CEs with area > 6,000 km**2 and < 20,000 km**2, (length ~100 km)

Class 3:

third quartile of CE spectrum--CEs with area > 20,000 km**2 and < 60,000 km**2, (length ~250 km)

Class 4:

third quartile of CE spectrum--CEs with area > 60,000 km**2, (length >250 km)