Dust-induced radiative feedbacks in north China: A dust storm episode modeling study using WRF-Chem
Dust-induced radiative feedbacks in north China: A dust storm episode modeling study using WRF-Chem
复制标题
中国北方沙尘引起的辐射反馈：使用 WRF-Chem 进行沙尘暴事件建模研究
DOI：
10.1016/j.atmosenv.2016.01.019
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发表时间：
2016-03-01
影响因子：
5
通讯作者：
Fu, Congbin
中科院分区：
文献类型：
--
作者：
Liu, Lixia;Huang, Xin;Fu, Congbin
利用气象-化学-气溶胶在线耦合模型WRF-Chem研究了2011年4月上旬典型亚洲沙尘暴期间华北地区沙尘气溶胶的辐射强迫和行星边界层（PBL）的辐射反馈。沙尘引起的地表和大气日平均辐射强迫（RF）在戈壁沙漠上空分别为21.1 W m（-2）和12.7 W m（-2），在华北平原（NCP）顺风区分别为-13.1 W m（-2）和4.8 W m（-2）。相比之下，短波辐射的辐射扰动幅度大约是长波辐射的两倍。白天，当太阳辐射占主导地位时，灰尘引起的地表冷却和大气加热增加了PBL稳定性，导致PBL高度（PBLH）降低约90 m，风速降低最多0.4 m s(-1)。相反，地面辐射的辐射强迫在夜间引起相反的反应，特别是在顺风地区。虽然白天风速减弱抑制了沙尘排放，但夜间较高的PBLH和较大的通气量将更多的沙尘颗粒抬升到更高的高度（平均上升75 m），延长了沙尘在大气中的停留时间，进一步加剧了顺风区的沙尘负荷。考虑到沙尘辐射反馈，模型预测的气温垂直剖面与相应观测结果之间的差距显着缩小，这表明沙尘暴期间 PBL 气象学中沙尘辐射相互作用的重要性。 (C) 2016 Elsevier Ltd. 保留所有权利。
Radiative forcing of dust aerosol and the radiative feedbacks on the planetary boundary layer (PBL) in North China during a typical Asian dust storm in the early April of 2011 was investigated by an online coupled meteorology-chemistry-aerosol model WRF-Chem. Dust-induced daily mean radiative forcing (RF) at the ground surface and in the atmosphere were estimated to be 21.1 W m(-2) and 12.7 W m(-2), respectively, over Gobi desert, and -13.1 W m(-2) and 4.8 W m(-2), respectively, in downwind region over the North China Plain (NCP). Comparatively, radiative perturbation on short-wave radiation was approximately twice that on long-wave radiation in magnitude. In the daytime, when solar radiation dominated, the surface cooling and atmospheric heating due to dust increased PBL stability, leading to reductions of PBL height (PBLH) about 90 m and decreases in wind speed up to 0.4 m s(-1). On the contrary, the radiative forcing in terrestrial radiation caused an opposite response at night, especially in the downwind region. Although dust emission was repressed by weakened wind speed during daytime, the elevated PBLH along with larger deflation at night lifted more dust particles to higher altitude (by up to 75 m in average), which prolonged dust residence time in the atmosphere and further intensified dust loading in downwind areas. Taking dust radiative feedbacks into consideration notably narrowed gaps between model-predicted air temperature vertical profiles with corresponding observations, suggesting a significant importance of dust-radiation interaction in PBL meteorology during dust storms. (C) 2016 Elsevier Ltd. All rights reserved.