VIIRS/JPSS1 Surface Reflectance Daily L3 Global 0.05 Deg CMG NRT

The VJ109CMG_NRT is a Near Real Time (NRT) daily surface reflectance Climate Modeling Grid Version 2 product which provides an estimate of land surface reflectance from the NOAA-20 (previously called JPSS1) Visible Infrared Imager Radiometer Suite (VIIRS) sensor. Data are provided for three imagery bands (I1-I3) and nine moderate resolution bands (M1-M5, M7, M8, M10, M11) at 0.05 degree (~5,600 meter) resolution. The data are corrected for atmospheric conditions such as the effects of molecular gases, including ozone and water vapor, and for the effects of atmospheric aerosols. This product uses a weighted average of the best quality observation and is formatted as a CMG for use in climate simulation models. This product includes the twelve reflectance bands, five moderate resolution brightness temperature bands (M12-M16) and information layers representing relative azimuth angle, sensor zenith angle, solar zenith angle, reflectance band quality, time of day, and number mapping.

Surface reflectance is obtained by adjusting top-of-atmosphere reflectance to compensate for atmospheric effects. Corrections are made for the effects of molecular gases, including ozone and water vapor, and for the effects of atmospheric aerosols. The inputs to the surface reflectance algorithm include top-of-atmosphere reflectance for the VIIRS visible bands (VJ102MOD, VJ102IMG), the VIIRS cloud mask and aerosol product, aerosol optical thickness, and atmospheric data obtained from a reanalysis (surface pressure, atmospheric precipitable water, and ozone concentration).

All surface reflectance products are produced for daytime conditions only. The product is produced under all atmospheric conditions except for night and oceans. Pixels when not produced are replaced by fill values in the Level-2 and Level-2G products.

For more information read Suomi-NPP VIIRS Surface Reflectance User's Guide at https://viirsland.gsfc.nasa.gov/PDF/VIIRS_Surf_Refl_UserGuide_v2.0.pdf

or

visit VIIRS Land website at https://viirsland.gsfc.nasa.gov/Products/NASA/ReflectanceESDR.html

VJ109CMG_NRT为近实时（NRT）每日地表反射率气候建模网格第2版本产品，该产品基于NOAA-20（原名JPSS1）可见光红外成像仪辐射计套装（VIIRS）传感器的估算地表反射率。数据涵盖三个图像波段（I1-I3）和九个中分辨率波段（M1-M5，M7，M8，M10，M11），分辨率为0.05度（约5,600米）。数据经过对分子气体（包括臭氧和水蒸气）和大气气溶胶效应的校正。该产品采用加权平均最佳观测值，并以CMG格式编排，以便在气候模拟模型中使用。产品包含十二个反射率波段，五个中分辨率亮度温度波段（M12-M16），以及表示相对方位角、传感器天顶角、太阳天顶角、反射率波段质量、白天时间和映射数量的信息层。

地表反射率通过调整大气顶反射率以补偿大气效应而获得。校正包括分子气体（包括臭氧和水蒸气）及大气气溶胶效应的影响。地表反射率算法的输入包括VIIRS可见波段（VJ102MOD，VJ102IMG）的大气顶反射率，VIIRS云掩膜和气溶胶产品，气溶胶光学厚度，以及从再分析中获得的大气数据（地表气压、大气可降水和臭氧浓度）。

所有地表反射率产品仅针对白天条件生产。产品在所有大气条件下生产，除了夜间和海洋。未生产时的像素在Level-2和Level-2G产品中由填充值替换。

欲获取更多信息，请参阅Suomi-NPP VIIRS地表反射率用户指南，链接为https://viirsland.gsfc.nasa.gov/PDF/VIIRS_Surf_Refl_UserGuide_v2.0.pdf，或访问VIIRS陆地网站，链接为https://viirsland.gsfc.nasa.gov/Products/NASA/ReflectanceESDR.html。