北大西洋沙尘与大气稳定度以及层云的关系

来自于西北非洲的沙尘粒子经常被输送到北大西洋(5 0°W～ 2 0°W,1 0°N～ 2 5°N)区域,夏季 7月份最为明显,沙尘输送带位于两逆温层之间.沙尘的辐射效应主要体现在冷却海表面而加热低对流层,因此沙尘有可能通过影响大气垂直稳定度从而影响海洋层云.试图通过分析 1 984年至 1 989年共 6年的7月份沙尘气溶胶、云观测资料来揭示沙尘气溶胶与大气稳定度以及层云之间的相互关系.结果表明,沙尘气溶胶能够通过影响大气稳定度而对层云产生影响,尽管该信号由于受到其他因素的干扰不容易提取出来

Dust, Stability and Stratus Cloud Cover over the Subtropical North Atlantic Region

Massive dust aerosols from the Northwest Africa exporting to the research region (50°W～20°W, 10°N～25°N) during the summer season, with a peak in July, are regularly ob-served by satellite. Dust aerosols are confined within the layer between two inversions. Themain effect of them is to heat the lower troposphere, but cool the surface, so the presence ofdust may cause a stabilizing effect on the temperature lapse rate, then affect the ocean low-lev-el stratus cover. Attempt to illustrate these relations based mainly on the satellite measure-ment of cloud and dust amount in July for six years (1984～1989). The results show that, inthis location, the presence of dust may influence the stratus cover through media of static sta-bility, although the signal is not easy to be revealed due to a few disturbances of undesirablefactors.