Ship Tracks: A Geographical and Statistical Study
Abstract
Anomalous cloud lines are frequently seen in satellite images as curvilinear features. These cloud lines or ship tracks are likely due to products of ship-produced hot exhaust gases that are expelled into the atmosphere, increasing the aerosol concentration in the ship track plume. NOAA 9 and 10 AVHRR data are sensitive to cloud droplet size and show the ship tracks as increases in radiance due to reflectance. Twenty eight NOAA 9/10 satellite passes are analyzed. Twenty two of the passes are found to contain a total of 316 ship tracks which is significantly more than that expected by earlier ship track studies. An existing ship track detection algorithm is used to conduct a statistical comparison of ship track and non-ship track, or ambient pixel reflectance of the NOAA 9 and 10 AVHRR channels 1 (0.63 um), 3 (3.7 um), and 4 (11 um). The results of the statistical analysis confirm, as found in previous studies, that the ship track pixels displayed a significant increase in values for channels 1 and 3 and a very slight increase for channel 4.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1992
- Accession Number
- ADA261297
Entities
People
- John W. Lutz
Organizations
- Naval Postgraduate School