KRASNOYARSK, August 5. /TASS/. The intensity of wildfires increased over past 20 years in a significant part of Siberia's Arctic zone, the Krasnoyarsk Scientific Center of the Russian Academy of Sciences' Siberian Branch said in a release.
"A team of Krasnoyarsk scientists, featuring researchers from the Krasnoyarsk Scientific Center of the Russian Academy of Sciences' Siberian Branch, has analyzed satellite data of the past 23 years to find that wildfires in that region have become more frequent, and their burning intensity has been growing. Over recent two decades, an increase in the heat output from wildfires has been recorded in the most part of Siberia's Arctic zone," the release reads.
Highly intensive wildfires have been reported in Arctic Siberia's eastern part, where larch forests predominate. The wildfires' intensity there is twice higher than in the zone's western regions. Researchers have recorded a decrease in burning intensity only in a small area of the macroregion - in places with tundra vegetation and high humidity. Such territories do not suffer much from wildfires.
"Wildfires in Siberia's Arctic zone are not just a local environmental problem. They cause emissions of carbon that previously was "trapped" in the permafrost, thus adding to the global warming. Besides, wildfires in those latitudes cause long-term changes in ecosystems, including the permafrost degradation, changes in vegetation cover and in soil hydrology," the release quoted senior researcher at the Sukachev Institute of Forest (the Russian Academy of Sciences' Siberian Branch) Evgeny Ponomarev as saying.
Scientists explain the growing wildfire intensity and frequency by changes in weather conditions and the ongoing climate warming, which develops in the Arctic quicker than anywhere else. In Arctic Siberia's most vulnerable locations, extreme wildfire seasons happen about every five years and their areas grow by 2-4 times relative to the annual average. Scientists attribute this to the increasing anticyclonic activity, which forms long-term droughts. In drought, intense solar heating increases evaporation and lowers air humidity thus leading to a fairly rapid depletion of moisture in the soil, plant litter and forest combustible materials - the main components of burning.