【摘要】 现有的沙尘气溶胶数值预报模式大多是单向模式,即只考虑气象场对沙尘气溶胶的输送作用,而忽略沙尘气溶胶的辐射效应对气象场的反馈作用。本文利用一个考虑了沙尘气溶胶短波辐射效应的天气-沙尘双向模式,对南疆盆地一次冷空气东侵而引起的沙尘天气进行数值模拟。通过比较考虑与不考虑辐射效应的两组试验,分析了在沙尘暴-强浮尘过程中沙尘辐射效应对气象要素和沙尘输送的影响,结果表明:沙尘辐射效应的考虑明显改进后期强浮尘天气过程中海平面气压变化、地面气温日变化和气温垂直变化的预报;前期沙尘暴过程沙尘辐射效应引起中低层主导风增大,但同时使起沙量降低及沉降量减少;沙尘辐射效应与地形的共同作用使沙尘的沉降量比起沙量减少的更显著,从而使盆地内浮尘天气维持。更多还原

【Abstract】 To study the radiative effect of dust aerosols on synoptic-scale system and the dust transport,an interactive weather-dust model including shortwave radiative effect of dust aerosols is developed.The change of temperature caused by radiative effect of dust aerosols is on-line fed back to the weather model.A dust storm caused by the cold front occurring in the south of Xinjiang during the period of 11 to 16 March 2006 is analyzed with the model.Two parallel simulations are done,one including the radiative effects of dust aerosols(RAD) and the other without it(CTL).A comparison of the two tests showed that: 1) Incorporation of radiative effect of dust can well improve simulations of diurnal changes of surface temperature,vertical changes of air temperature and variation of the sea level pressure during the high floating dust period.2) During the dust storm period,the radiative effect of dust aerosols can cause large increases in dominant wind speeds at lower model levels but will reduce dust emissions and deposition.3) A combination of the radiative effect of dust and the basin terrain influences leads to decreasing more deposition of dust aerosols than emission,therefore,it helps maintain the floating dust weather.更多还原