Changes in forest fire danger for south-western China in the 21st century

Abstract

This paper predicts future changes in fire danger and the fire season in the current century for south-western China under two different climate change scenarios. The fire weather index (FWI) system calculated from daily outputs of a regional climate model with a horizontal resolution of 50×50km was used to assess fire danger. Temperature and precipitation demonstrated a gradually increasing trend for the future. Forest fire statistics for 1987–2011 revealed that the FWI, initial spread index and seasonal severity rating were significantly related to the number of forest fires between 100 and 1000ha in size. Over three future periods, the FWI component indices will increase greatly. The mean FWI value will increase by 0.83–1.85, 1.83–2.91 and 3.33–3.97 in the periods 2011–2040, 2041–2070 and 2071–2100. The regions with predicted FWI increases are mainly in central and south-eastern China. The fire season (including days with high, very high and extreme fire danger ratings) will be prolonged by 9–13, 18–21 and 28–31 days over these periods. This fire season extension will mainly be due to days with an extreme fire danger rating. Considering predicted future changes in the forest fire danger rating and the fire season, it is suggested that climate change adaptation measures be implemented.