PARENT SESSION
Oral Session # 40: Fire Ecology II: Forests.
Presiding: D Falk
Wednesday, August 6. 8:00 AM to 11:30 AM, SITCC Meeting Room 102.

Investigating potential climate-induced change in fire return intervals for 1999, 2000, and 2001 in boreal Siberia.

Soja, Amber^{*,1, 2}, Shugart, Herman¹, Stackhouse, Paul², Sukhinin, Anatoly³, Conard, Susan ⁴, ¹ University of Virginia, Charlottesville, Va, USA² NASA Langley, Hampton, Va³ Sukachev Institute of Forestry, Krasnoyarsk, Siberia, Russia⁴ USDA Forest Service, Arlington, Va

ABSTRACT- Evidence of fire-induced, climate-related change is investigated in boreal Siberia by comparing calculated fire return intervals with expected fire return intervals. Boreal regions are particularly significant because these are the regions that will initially experience climate change and this is where the largest reservoir of terrestrial carbon resides. Under current climate change scenarios, fire season length and fire weather severity are expected to increase. Because temperatures have already increased across Siberia in the last decades, it follows that the interval between fire occurrence at particular sites is expected to decrease. The hypothesis to be tested is fire return intervals will decrease. Satellite-based data is used to estimate area burned, which is overlaid on an ecoregion map to calculate area burned in each ecoregion across Siberia. Data from 1999, 2000, and 2001 are used to calculate average fire return intervals for each ecosystem, as well as an average boreal forest fire return interval. Results from this investigation show that fire return intervals are either equivalent to or greater than expected fire return intervals, which was not expected. However, both an underestimation in area burned and the minimal number of years analyzed could result in anomalous fire return intervals. Interestingly, the expected percentage of young stands, which is calculated based on the estimated average boreal forest fire return interval (159 years), is similar to published estimates of the percentage of existing young stands (6.5%).

Key words: climate, boreal, avhrr, wildfire