Effect of wavelength selection on characterization of fire size and temperature
Abstract:Over the past two decades, Dozier's 1981 retrieval method has been used with observations from various moderate-resolution (∼ 1 km) spaceborne sensors to estimate the instantaneous sub-pixel area and temperature of wildfires. The method requires simultaneous observations at two different wavelengths. Traditionally these wavelengths have resided in the middle- and long-wave infrared regions, for example the 4 and 11 µm channels of the NOAA Advanced Very High Resolution Radiometer (AVHRR). Development of recent and upcoming sensors, including the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Visible/Infrared Imager/Radiometer Suite (VIIRS), have spawned interest in using other wavelength combinations, particularly in the short-wave infrared, for sub-pixel active fire characterization. We demonstrate that for realistic wildfires, which are composed of both flaming and smouldering components, the location of these two wavelengths can cause large differences in the fire temperatures and areas that are retrieved using Dozier's method. In the worst case considered, differences of 250 K in temperature and 80% in area were observed.
Document Type: Research Article
Affiliations: 1: Science Systems and Applications, Inc., NASA Goddard Space Flight Center, Code 923, Greenbelt, MD 20771, USA;, Email: email@example.com 2: Department of Geography, University of Maryland, College Park, MD 20742, USA
Publication date: 2003-09-01