2022 年 18 巻 p. 218-224
Ensemble future climate projections were performed using the Meteorological Research Institute Earth System Model version 2.0 (MRI-ESM2.0) for sand and dust storms (SDS), which have a significant social and climatic impact on East Asia. A replication experiment using MRI-ESM2.0 reproduced the decreasing trend of SDS emissions in the Gobi Desert in the early 21st century. Prediction experiments using MRI-ESM2.0 in Coupled Model Intercomparison Project phase 6 future scenarios indicated no considerable differences in the total amount of SDS emissions in the Gobi Desert for 2015-2100; however, SDS emissions increased with warmer scenarios in spring and autumn. In particular, March in the highest warming scenario (SSP5-8.5) exhibited an annual increase rate of 3.0% in SDS emissions for the years 2015-2100. Friction velocity was highly correlated with SDS emissions, with a correlation of ∼0.6 for all climate scenarios throughout the year. In spring and autumn, snow cover exhibited a low negative correlation with SDS emissions, while ground temperature exhibited a positive correlation. The increase in SDS emissions and subsequent dust transport by midlatitude westerlies in spring and autumn during accelerated warming scenarios could be attributed to the changes in friction velocity and erodibility due to the decrease in snow accumulation.
