Satellite imagery gives clear picture of Russia's boreal forest fires

Abstract

Boreal forest fires in Russia in 1998 may have covered a much larger area than originally reported and may have been mostly crown fires, releasing more greenhouse gases into the atmosphere than surface fires. These conclusions are based on analysis of Advanced Very High Resolution Radiometer (AVHRR) data and discussions with Russian fire officials. A more complete analysis of AVHRR data collected since 1980 is underway to determine overall fire patterns in Russia's boreal forests. The year 1998 was an extreme fire year throughout the boreal forest regions of both North America and Eurasia. Over 11 million hectares burned. In Alaska and Canada alone, 4.7 million hectares of boreal forests burned in 1998, according to estimates by national fire monitoring systems in those places.

A Discriminant Analysis Model of Alaskan Biomes Based on Spatial Climatic and Environmental Data

“…Data from the boreal forest of western Canada showing that the average area burnt has doubled in the past 20 years (Kasischke et al, 1999) are consistent with this ex pec ta tion. Increases in fire frequency and extent are also pre dict ed to produce a shift in vegetation from a conifer-dominated to a deciduous-dominated forest (Rupp et al, 2000b(Rupp et al, , 2001(Rupp et al, , 2002, which, in turn, could provide biotic feedback to regional warming .…”

Using <sup>14</sup>C, <sup>13</sup>C, <sup>18</sup>O and <sup>17</sup>O isotopic variations to provide insights into the high northern latitude surface CO inventory

“…This feature also persisted for several months, indicating that these levels were characteristic for the entire high northern latitudes in summer 1997. The most likely cause of the low summer minimum is that 1997 was indeed an exceptionally clean year regarding CO source emissions, which is supported by official statistics showing that biomass burning was low throughout the Russian and North American boreal forest in 1997 (Johnston, 1999;Kasishke et al, 1999;Wotawa et al, 2001). The 1997 CO anomaly has a large effect on the δ 13 C signature during summer 1997, when δ 13 C values reach almost −29‰.…”

“…With a total of 4.7 million hectares burnt in Canada, 1998 is among the five worst years regarding forest fires, whereas only 625 000 and 1.9 million hectares were burnt by wildfires in 1997 and 1996, respectively, the two other burning seasons covered by our study (Johnston, 1999). For Russia, only 2.65 million hectares of burnt forest have been officially reported in 1998, but recent satellite imagery has exposed that the actual area burnt in Russia in 1998 may have been as high as 10 million hectares (Kasishke et al, 1999). In the three major regions (Khabarovsk, Amur, Sakhalin Island), 4% of the entire land area burned.…”

An Analysis of Seasonal and Decadal-long Variations of Aerosols over the Asian Pacific Region using NOAA/AVHRR Data

“…It is worth noting that in spring in mid-latitudes a zone of large t a is extending eastward, at least, to 170 E. It is in- teresting that in summer the northern areas are predominated by small particles of finemode, with moderately large t a and quite large a. The aerosols might be caused by the G-P conversion from activated emission of DMS (dimethylsulfide) from the sea, as well as by extensive biomass burning in Siberia (e.g., Kasischke et al 1999;Tanimoto et al 2000). Figure 3 shows the latitude-year plots of the monthly-mean aerosol parameters (t a and a), averaged over the longitude range (zonal-mean) in the analyzed region.…”

“…The former case could be caused by an increased emission of sulfate particles in Asia (Streets et al 2000), and partly due to frequent Kosa events, particularly, occurred in 1996 and 2000 (Arao and Aoki 2001). While the latter case might be due to extensive forest-fires in Siberia, particularly in the 1998 summer (Kasischke et al 1999;Tanimoto et al 2000).…”