基于静止气象卫星的动态沙尘检测方法

摘要

针对沙尘检测的有效参数,气象卫星观测的11μm与12 μm通道亮温变化信息随时空变化具有显著差异,容易产生较大误判这一问题,利用新一代静止气象卫星Himawari-8,通过建立晴空11μm亮温及其与12 μm亮温差背景场,结合沙尘大气条件下11μm与12 μm通道的亮温变化特征,提出了基于动态阈值的静止气象卫星沙尘遥感检测方法,并有效应用于2016年3月1-20日中国西北地区沙尘天气信息的提取.实验结果表明,该方法不仅可显著提升沙尘检测的精度,还可以应用于夜间沙尘信息的提取,为中国沙尘天气研究提供了一种可靠的手段.%The difference of brightness temperature between 11 μm and 12 μm channel,observed by meteorological satellite,provides an effective parameter for the dust detection.However,the difference changes with the spatial and temporal variation,which easily results in mistakes in dust detection.To overcome this difficulty,it proposes a dust detection method based on dynamic threshold of geostationary meteorological satellite.The clear-sky background field of 11 μm brightness temperature and its difference with 12 μm were established by making use of Himawari-8 the new generation of geostationary meteorological satellite.While combining with the bright temperature variation characteristics of 11 μm and 12 μm channel under the conditions of dust atmosphere,the detection was performed.The method was applied in the dust information extraction in the northwest of China from March 1 to 20,2016.The experimental results show that this method can not only improve the accuracy of dust detection,but also be applied to extract the dust information at night.Consequently,this method provides a reliable means for the study of the dust weather in China.