RUI: Visual and Spectral Properties of Tropospheric Haze

本研究项目将采用一种全新的方法，利用高光谱和多光谱成像技术对大气雾霾进行光学遥感。科学目标是首次在可见光波段测量对流层雾霾的综合角度和光谱特性。由于没有测量到的雾霾光谱的角度分布，这些数据集将构成一个全新的工具，用于审查大气辐射传输模型。第二个科学目标是分析雾霾的色度和光度特性的范围，这些重要的视觉测量比光谱测量更容易理解。这个项目的智力价值是双重的。首先，它将允许对雾霾光学特性进行系统的分析，这是现在不可能的，绘制对流层雾霾光谱的实际分布，作为太阳高度、散射角和雾霾气溶胶光学深度的函数。其次，该研究将提供基于RGB数码相机的多光谱成像系统的比色、光度和光谱精度的独立测试。当通过线性偏振器获得高光谱数据时，高光谱数据也可用于独立测试现有的多光谱技术，用于绘制雾霾偏振。对雾霾偏振的光谱测量很少，本研究获得的数据将是独一无二的。除了推进大气科学本身，这项研究将(1)有利于科学教育，(2)对公众产生更广泛的影响。在第(1)点上，数字成像技术将用于日常课堂教学和海军学院学员为期一年的荣誉研究项目。在第(2)点上，更好地理解雾霾的角度和光谱分布在提高司机、飞行员和水手的能见度、从单个室外图像估计物体距离以及提供测量空气污染特性的新方法等领域具有实际应用价值。

This research project will employ a fundamentally new approach to optical remote sensing of atmospheric haze, using both hyperspectral and multispectral imaging techniques. The scientific objective is to measure for the first time the combined angular and spectral properties of tropospheric haze at visible wavelengths. Because no such measured angular distributions of haze spectra exists, these datasets will constitute an entirely new tool with which to vet atmospheric radiative transfer models. A second scientific objective is to analyze the range of haze's colorimetric and photometric properties, important visual measures that are little better understood than its spectral ones.The intellectual merit of the project is twofold. First, it will permit a systematic analysis of haze optical properties that is now impossible, mapping actual distributions of tropospheric haze spectra as functions of sun elevation, scattering angle, and haze aerosol optical depth. Second, the research will provide independent tests of the colorimetric, photometric, and spectral accuracies of multispectral imaging systems based on RGB digital cameras. When acquired through a linear polarizer, hyperspectral data also can be used to independently test existing multispectral techniques for mapping haze polarization. Spectral measurements of haze polarization are rare, and data obtained in this study will be unique.Beyond advancing atmospheric science itself, the research will (1) benefit science education and (2) have broader impacts on the general public. On point (1) digital imaging techniques will be used both in daily classroom instruction and in year-long honors research projects for Naval Academy midshipmen. On point (2), better understanding the angular and spectral distribution of haze has practical applications in such areas as improving visibility for drivers, pilots, and sailors, estimating object distances from single outdoor images, and providing new ways to measure air pollution properties.