The impact of climate change on aeolian desertification in northern China: Assessment using aridity index

Abstract

At present, there is no consensus regarding the degree to which climate change and human activity affect aeolian desertification in northern China. The purpose of this study is to assess quantitatively the temporal and spatial impacts of climate change on aeolian desertification. The aridity index (AI) was used as an indicator of climate change and its relationship with regional aeolian desertification was analyzed over the period 1975–2010. Three different scenarios were set up on the basis of possible combinations of variations induced by human intervention and climate change. Results indicate that between 1975 and 1990, climatic factors triggered aeolian desertification development across an area of 49,423 km2, which accounts for 63% of the total area affected by aeolian desertification, whereas climate-related reversion of aeolian desertification occurred across 919 km2, accounting for 64% of the area that experienced aeolian desertification reversal. Between 1990 and 2000, climate-triggered aeolian desertification covered an area of 58,737 km2, which was 72% of the total development area, and aeolian desertification reversion related to climatic factors occurred across 7698 km2, or 28% of the total reversion area. Between 2000 and 2005, climate-triggered aeolian desertification covered an area of 821 km2, accounting for 19% of the total development area, and aeolian desertification reversion occurred across 45,125 km2, which was 83% of the total reversion area. Finally, between 2005 and 2010, climate-related aeolian desertification occurred across 2893 km2, accounting for 36% of the total development area, whereas aeolian desertification reversion occurred across 31,839 km2, accounting for 70% of the total reversion area. These results indicate that the effect of climate change on aeolian desertification development weakened between 1975 and 2010, whereas its effect on aeolian desertification reversion strengthened. In the future, it is suggested that the aeolian desertification process (development or reversion) should be referred first, before considering the relative effects of climate change and human interventions.