Atmospheric Sciences Program, Department of Physics, University of Nevada, Reno, NV 89557, USA,
Division of Atmospheric Sciences, Desert Research Institute, Reno, NV 89512, USA.
Sensors (Basel). 2018 Oct 17;18(10):3504. doi: 10.3390/s18103504.
Bright surfaces across the western U.S. lead to uncertainties in satellite derived aerosol optical depth () where is typically overestimated. With this in mind, a compact and portable instrument was developed to measure surface albedo on an unmanned aircraft system (UAS). This spectral albedometer uses two Hamamatsu micro-spectrometers (range: 340⁻780 nm) for measuring incident and reflected solar radiation at the surface. The instrument was deployed on 5 October 2017 in Nevada's Black Rock Desert (BRD) to investigate a region of known high surface reflectance for comparison with albedo products from satellites. It was found that satellite retrievals underestimate surface reflectance compared to the UAS mounted albedometer. To highlight the importance of surface reflectance on the from satellite retrieval algorithms, a 1-D radiative transfer model was used. The simple model was used to determine the sensitivity of with respect to the change in albedo and indicates a large sensitivity of retrievals to surface reflectance for certain combinations of surface albedo and aerosol optical properties. This demonstrates the need to increase the number of surface albedo measurements and an intensive evaluation of albedo satellite retrievals to improve satellite-derived . The portable instrument is suitable for other applications as well.
美国西部的亮面会导致卫星反演气溶胶光学厚度（）出现不确定性，通常会导致反演值偏高。考虑到这一点，我们开发了一种紧凑、便携的仪器，以便在无人机系统（UAS）上测量表面反照率。该光谱反照率计使用两个 Hamamatsu 微型光谱仪（范围：340-780nm）来测量表面的入射和反射太阳辐射。该仪器于 2017 年 10 月 5 日部署在内华达州的黑岩沙漠（BRD），以调查一个已知高表面反射率的区域，以便与卫星反照率产品进行比较。结果发现，与 UAS 搭载的反照率计相比，卫星反演值低估了表面反射率。为了强调卫星反演算法中表面反射率的重要性，我们使用了一维辐射传输模型。该简单模型用于确定反照率的变化对的敏感性，并表明在某些表面反照率和气溶胶光学特性的组合下，对的反演值有很大的敏感性。这表明需要增加表面反照率测量的数量，并对反照率卫星反演进行密集评估，以改进卫星反演的。该便携式仪器也适用于其他应用。
