The Extended Time Observation (ETO) program will directly support the ISCCP and GCM validation efforts. The ETO data will consist of satellite observations, special ground stations with lidar and surface radiation measurements, and conventional meteorological observations. These data will provide a means of extending the results derived in the more detailed Intensive Field Observation Program intercomparison studies to larger time and space scales.
The Extended Time Observations are subdivided into two space scales:
Extended area and Limited area. The extended area data set is meant to provide
data over a large geographical area where occurrences of cirrus and stratocumulus
cloud systems may be found in a variety of geographical locations; and to allow
for multi-satellite, multiple-view observations of these systems. The limited
area data set is geographically specific to the location and surrounding area
of surface observing sites being maintained throughout the FIRE-I experiment.
OBJECTIVES
The specific objectives of the ETO are:
i. to provide a statistical description of existing cirrus and stratocumulus cloud fields,ii. to characterize the horizontally averaged radiative characteristics (-250 km) of cirrus and stratocumulus cloud fields, and
iii. to relate cirrus and stratocumulus cloud fields to accompanying larger scale meteorological fields, as in a GCM.
Statistical descriptions of cirrus and marine stratocumulus cloud fields
will be multi-dimensional frequency distributions on a spatial scale of (250 km).
These distributions will characterize cloud field properties including areal cloud
fraction, cloud top height and temperature, cloud visible reflectance and shortwave
albedo and cloud infrared emittance.