Detection of forest-fire smoke plumes by satellite imagery
In support of the Canadian research programmes for Long-Range Transport of Air Pollutants (LRTAP), the present study was undertaken to examine the feasibility of using satellite imagery to detect large-scale pollution episodes. Atmospheric Environment Service (AES) satellite imagery records were scrutinized in conjunction with meteorological and air quality data. The LRTAP from large forest fires more than 5000 km away was identified. Further evidence was obtained from analysis of digital data from NOAA satellites by employing a ‘false colour’ technique. Computer enhanced images suggested that a smoke plume was well-defined and separated from clouds when smoke crossed over a lake and ocean. It is suggested that many large forest fires with resulting intense smoke were due to atmospheric lightning. In particular, the area influenced by the widespread smoke, from large fires in northwestern Canada on 27–28 August 1981, exceeded the area covered by dust and smoke clouds in the low-level atmosphere from the Mount St Helens volcanic eruption on 18 May 1980.