Causes of the remarkable increase in dust activities in inland Asia since the late Miocene: insights from regional climate simulations

This study explored the impact of regional tectonic uplift and desertification on Asian dust emissions during the dust season by using a regional climate model (RegCM4.1), and the results showed that the surface uplifting-promoted dust emissions in semi-arid areas and the Tibetan Plateau, while the emergence of deserts enhanced the dust emissions in the major dust source areas of inner Asia. These two factors accounted for 20% and 80% of the increase in dust emissions in inland Asia, respectively. Both events enhanced the surface dust emissions and airborne dust loading by changing the local circulation and suppressing soil moisture and near-surface water vapour. The thermal effect of the uplift of the NTP suppressed soil moisture by 20% and near-surface water vapour by 50% in inland Asia, and its dynamic effect enhanced the westerly winds at 600 hPa and provided power for dust transport at high altitudes. The formation of deserts directly suppressed soil moisture by 50% and near-surface water vapour by 30%, and the radiative effects of the emitted dust aerosols enhanced the surface westerly winds and provided power for dust emissions and transport near the surface.