In addition, this estimate is critical for determining net biome productivity for this major terrestrial carbon reservoir. While it is generally accepted that the boreal forest represents a significant terrestrial carbon sink, it has been suggested that the strength of this sink might be significantly reduced (or even reversed so that the boreal forest is a net carbon source) as a result of increased fire activity due to climate warming (Kasischke et al. 1995b). Estimates of fire carbon emissions for the North American boreal forest show that in some areas, more than 200 g C m^-2 yr^-1 was released during the period of 1980 to 1994, which far exceeds NEP values for this region (40 to 80 g C m^-2 yr^-1) (French et al. 1999).

The outcome of this study will be important to several groups of scientists. First, the results will be important to scientists quantifying the global terrestrial carbon budget. In order to determine net biome production, emissions from biomass burning are needed. Second, the results will also be important to those scientists trying to quantify the variations in the atmospheric CO₂ record. Finally, in addition to producing estimates of CO₂ emissions, we will also provide estimates of emissions of other important greenhouse gases from fire, such as methane and carbon monoxide.The use of the unique data sets provided by NASA's Earth Science Enterprise is central to the success of this project. In particular, the estimates of fire location and area provided through analysis of AVHRR, MODIS and Landsat imagery and the estimates of fire severity produced from Landsat imagery are critical to reducing uncertainties in boreal forest fire emissions of CO₂ and other greenhouse gases.