NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Cloud-screening for Africa using a geographically and seasonally variable infrared thresholdA spatially variable monthly, infrared cloud-threshold data base has been used to screen cloud-contaminated observations from radiances measured by the NOAA-9 AVHRR over Africa. Cloud-screening through a monthly average infrared threshold based on measured surface air temperature, which is geographically dependent, shows an improvement over using a seasonally and geographically independent thermal cloud threshold of 287 K. It is found that differences in cloud-screening for these two thresholds occur for cases of lower altitude clouds or subpixel clouds where the radiative temperature is higher than the 287 K infrared threshold, yet colder than the variable threshold developed by Stowe et al. (1988) for the Nimbus-7 global cloud climatology. The variable IR threshold is shown to be effective over persistently cloud-covered regions, such as the coastal region of the Gulf of Guinea, but may introduce some erroneous cloud identifications over mountains.
Document ID
19910056464
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Eck, T. F.
(ST Systems Corp. Lanham, MD, United States)
Kalb, V. L.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 15, 2013
Publication Date
June 1, 1991
Publication Information
Publication: International Journal of Remote Sensing
Volume: 12
ISSN: 0143-1161
Subject Category
Earth Resources And Remote Sensing
Accession Number
91A41087
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available