[A-CG39] Global Carbon Cycle Observation and Analysis

[ACG39-P03] Variation in vegetation activity in Mongolia over the past 40 years and analysis of its factors

*Reina WATANABE¹, Misaki Hase¹, Yuki Sofue², Kazuhito Ichii³ (1.Center for Environmental Remote Sensing Chiba University, 2.The University of Tokyo, 3.Chiba University)

Keywords:Mongolia, vegetation

In Mongolia, recent climate change and changes in human activity are having an impact on various surface environments. In particular, basic climate elements such as temperature and precipitation have a significant impact on the natural environment, and it is important to monitor these environmental conditions and the vegetation environment. In this study, we analyzed the relationship between climate elements and the vegetation environment in Mongolia using various data sets based on satellite data from the past 20 and 40 years. We used Google Earth Engine as the analysis platform. For long-term (40-year) vegetation data, we used a data set of vegetation indices and associated area indices from NOAA/AVHRR, and for medium-term (20-year) vegetation data, we used various products from the MODIS sensor. In Mongolia, we saw a decrease in vegetation activity from 1982 to 2000, and an increase after that. In particular, around 2000, the vegetation activity was low over a 40-year period due to severe drought. These changes corresponded to changes in the aridity index in the steppe region, and in some northern forest areas, they corresponded to changes in temperature.