利用卫星探测辐射的光谱依赖性来反演大气气溶胶粒子尺度分布,首先要建立反演算法并检验其可行性。本文参照文献[1]对暗的海洋上空MODIS资料的处理方法,针对大陆水库上空卫星探测MODIS辐射信号,利用6S(Second Simulation of the Satelli...利用卫星探测辐射的光谱依赖性来反演大气气溶胶粒子尺度分布,首先要建立反演算法并检验其可行性。本文参照文献[1]对暗的海洋上空MODIS资料的处理方法,针对大陆水库上空卫星探测MODIS辐射信号,利用6S(Second Simulation of the Satellite Signal in the Solar Spectrum)辐射模式建立一个查算表(Look-up table:LUT)来反演大气气溶胶粒子尺度分布;然后通过数值试验对所建立的查算表进行检验,讨论其方法的可行性。数值试验结果表明,查算表对大陆性气溶胶尺度分布有反演能力,但拟合误差sεl值随着气溶胶光学厚度的增加而增加。展开更多
The probability distribution analysis is per-formed for multi-timescale aerosol optical depth (AOD) using AErosol RObotic NETwork (AERONET) level 2.0 data.The maximum likelihood estimation is employed to determine the...The probability distribution analysis is per-formed for multi-timescale aerosol optical depth (AOD) using AErosol RObotic NETwork (AERONET) level 2.0 data.The maximum likelihood estimation is employed to determine the best-fit probability density function (PDF),and the statement that the fitting Weibull distribution will be light-tailed is proved true for these AOD samples.The best-fit PDF results for multi-site data show that the PDF of AOD samples with longer timescale in most sites tends to be stably represented by lognormal distribution,while Weibull distribution is a better fit for AOD samples with short timescales.The reason for this difference is ana-lyzed through tail characteristics of the two distributions,and an indicator for the selection between Weibull and lognormal distributions is suggested and validated.The result of this research is helpful for determining the most accurate AOD statistics for a given site and a given time-scale and for validating the retrieved AOD through its PDF.展开更多
文摘利用卫星探测辐射的光谱依赖性来反演大气气溶胶粒子尺度分布,首先要建立反演算法并检验其可行性。本文参照文献[1]对暗的海洋上空MODIS资料的处理方法,针对大陆水库上空卫星探测MODIS辐射信号,利用6S(Second Simulation of the Satellite Signal in the Solar Spectrum)辐射模式建立一个查算表(Look-up table:LUT)来反演大气气溶胶粒子尺度分布;然后通过数值试验对所建立的查算表进行检验,讨论其方法的可行性。数值试验结果表明,查算表对大陆性气溶胶尺度分布有反演能力,但拟合误差sεl值随着气溶胶光学厚度的增加而增加。
基金supported by funds from the Chinese Global Change Research Program (Grant No.2010CB951804)the National Natural Science Foundation of China (Grant No.40830103)the China Postdoctoral Science Foundation (Grant No.20100480436)
文摘The probability distribution analysis is per-formed for multi-timescale aerosol optical depth (AOD) using AErosol RObotic NETwork (AERONET) level 2.0 data.The maximum likelihood estimation is employed to determine the best-fit probability density function (PDF),and the statement that the fitting Weibull distribution will be light-tailed is proved true for these AOD samples.The best-fit PDF results for multi-site data show that the PDF of AOD samples with longer timescale in most sites tends to be stably represented by lognormal distribution,while Weibull distribution is a better fit for AOD samples with short timescales.The reason for this difference is ana-lyzed through tail characteristics of the two distributions,and an indicator for the selection between Weibull and lognormal distributions is suggested and validated.The result of this research is helpful for determining the most accurate AOD statistics for a given site and a given time-scale and for validating the retrieved AOD through its PDF.
