Investigation of Anomalous Cloud Features in 3.7 Micrometer Satellite Imagery.
Abstract
When band 3 (3.7 micrometers) daylight AVHRR imagery are examined, unique effects not present in the other four bands are observed. These effects include a higher radiance from cloud tops than from the sea-surface, unique ship exhaust tracks and the highlighting of areas of thin clouds, continental aerosol intrusion into marine air and ice clouds. These effects are due to the addition of various amounts of reflected solar radiance and thermal emitted radiance. In this thesis, three cases illustrating these effects are examined. The apparent temperature reversals result from clouds reflecting more solar radiation than the sea surface. Ship tracks and continental aerosol effects are due to altered size distributions caused by added ship exhaust pollutants or aerosols. The absorptivity of ice clouds is higher than water clouds, thus the sensed radiance from ice clouds is essentially only emitted, not reflected. Therefore, ice clouds appear colder than liquid water clouds in band 3. Keywords: Clouds; Satellite techniques; Visible; Near infrared; Infrared; Radiative transfer; Aerosol effects; Theses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1987
- Accession Number
- ADA183200
Entities
People
- John M. Rogers
Organizations
- Naval Postgraduate School