| 摘要: |
| 利用葵花-8(Himawari-8)卫星气溶胶光学厚度(Aerosol Optical Depth，AOD)数据三级(L3)资料，从年平均、逐月变化、季节变化、逐小时变化分析了东南沿海AOD的时空分布及其变化。结果表明：东南沿海空间分布特征为AOD沿岸线呈带状分布，且随离岸距离的增加AOD逐渐降低。多年 AOD平均高值区主要分布于福建沿海与台湾西部沿海海区(即台湾海峡两侧)。最低AOD出现在远离陆地的西太平洋海区；由于我国东海沿海近岸泥沙较多等原因，海水反射率很高，但是AOD产品在反演时下垫面仍用很小的值，造成了近岸AOD不真实的大值。东南沿海AOD在3月到达当年最大值，6月AOD为全年最小值；4个季节的AOD分布特征明显不同。春季AOD数值最大，冬季次之，夏秋最小；季节变化原因在春季是大环流背景下平流雾与太阳辐射的作用；夏季受到副高与太阳辐射的影响；秋季受到偏北风、冷空气起的主导作用；冬季受冷高压脊与“狭管效应”的共同作用。由于海陆风作用与海峡上光化学反应的相互影响，东南沿海AOD从08时到15时数值上升，在15时达到一天中最强的时刻，相对大值范围从台湾海峡两岸逐渐向海峡中部延伸。 |
| 关键词: 海洋气象学 葵花-8 气溶胶光学厚度 时空变化 东南沿海 |
| DOI：10.3969/J.ISSN.2095-4972.2019.03.003 |
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| 基金项目:福建省科技计划资助项目(2016Y0008)；国家自然科学基金资助项目(41461164007) |
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| Spatial and temporal distribution and variation of aerosol optical depth in coastal southeast China based on Himawari-8 satellite |
| LI Kai-lin,ZHANG Chun-gui,WANG Hong,CHEN Xiao-chen,CHEN Li |
| (1.Fujian Meteorological Information Center, Fuzhou 350001, China;2.Fujian Meteorological Institute, Fuzhou 350001, China; 3.Fujian Climate Center, Fuzhou 350001, China) |
| Abstract: |
| Based on the Himawari-8 Level3 Aerosol Optical Depth(AOD) data, parameters of annual mean, monthly variation, seasonal variation and hourly variation were used to analyze the spatial and temporal distribution and variatron of AOD. The results indicate that annual average AOD in coastal SE China forms a zonal distribution along the coast. With increased distance to the shore, the AOD gradually decreases. The highest area of annual averaged AOD appears in Fujian and western Taiwan coastal areas, i.e. in the two banks of Taiwan Strait. The lowest AOD area occurs in a remote waters of the West Pacific. Because of high suspended materials in the water in the eastern coast of China, the seawater reflection is high in the coastal SE China. However, the values of underlying surface used by AOD product was low during the retrieval, which lead to a falsehood and high value of AOD. The AOD in the coastal SE China reaches the highest in March, and decreases to the lowest in June. The temporal AOD mean pattern varies substantially with seasons and it comes to the highest in the spring, moderate in winter and autumn, and to the lowest in summer. The reason for seasonal variation is that the advection fog and solar radiation have great contributions to the AOD value in the spring circulation while AOD value is affected by the Subtropical High as well as the solar radiation in summer. In autumn, neverthless, northerly winds and cold air play an important role in AOD values. The combined impacts of the Cold Ridge and the funnel effects on AOD occurs in winter. Due to the common effects of landsea breeze and photochemical reaction in the Taiwan Strait, AOD rises from 8 a.m. to 15 p.m.. At 15 p.m. the value reaches the peak of the day. In the meantime the rather high AOD extends from the two banks to the middle Taiwan Strait. |
| Key words: marine meteorology Himawari-8 AOD spatial and temporal variation coastal southeast China |
