JPSS-2 CrIS IMG_COL: Array indices for collocated VIIRS observations V3.0 (SNDRJ2CrISL1BIMGC) at GES DISC

The Cross-track Infrared Sounder (CrIS) Level 1B Full Spectral Resolution (FSR) data files contain radiance measurements along with ancillary spacecraft, instrument, and geolocation data of the CrIS instrument on the Joint Polar Satellite System-2 (JPSS-2) platform. This platform is also know as NOAA-21 (National Oceanic and Atmospheric Administration).

The IMG product supplements the CrIS Level 1B (L1B) hyperspectral radiance product by providing collocated high-spatial resolution data from the Visible Infrared Imaging Radiometer Suite (VIIRS) imager located on the same platform. VIIRS radiance and cloud mask values are grouped and aggregated for every CrIS field of view (FOV) and made available in a format intended for use alongside the CrIS L1B data. The collocated VIIRS level 1 / cloud mask statistical summary (collection name SNDRJ2CrISL1BIMG) is the main product and consists of collocated CrIS field of views with the VIIRS cloud mask and radiances/reflectances. This can be thought of as a match-up between CrIS and VIIRS. The supplementary product, array indices for collocated VIIRS observations (SNDRJ2CrISL1BIMGC), product additionally makes available CrIS and VIIRS data array index values that result from the collocation process that is performed as part of producing IMG. These index values can be leveraged by end users to further augment CrIS data by extracting collocated observations from any additional VIIRS data products that aren’t already present in IMG.

The FSR files have 2,223 channels (*2211 apodized channels): 637 (*633) shortwave channels from 3.9 to 4.7 microns (2555 to 2150 cm-1), 869 (*865) midwave channels from 5.7 to 8.05 microns (1752.5 to 1242.5 cm-1), and 717 (*713)longwave channels from 9.1 to 15.41 microns (1096.25 to 648.75 cm-1). Each CrIS field-of-regard (FOR) contains 9 field-of-views (FOVs) arranged in a 3X3 array. The Level 1B files contain 30 FORs in the cross track direction and 45 in the along track direction. Data products are constructed on six minute boundaries.

The Visible Infrared Imaging Radiometer Suite (VIIRS) has 22 imaging and radiometric bands covering wavelengths from 0.41 to 12.5 microns. It provides the sensor data records for clouds, sea surface temperature, ocean color, and others. This IMG_COL product contains the colocation indices of the VIIRS pixels within each CrIS footprint.

跨轨道红外探测器（CrIS）第1B级全光谱分辨率（FSR）数据文件包含了沿CrIS仪器在联合极地卫星系统-2（JPSS-2）平台上的辐射度测量，以及辅助的航天器、仪器和地理定位数据。该平台亦被称作NOAA-21（国家海洋和大气管理局）。IMG产品通过提供位于同一平台上的可见光-红外成像仪（VIIRS）的高空间分辨率数据，对CrIS第1B级（L1B）高光谱辐射度产品进行补充。VIIRS的辐射度和云掩膜值按CrIS视场（FOV）分组并汇总，以适应与CrIS L1B数据一同使用的格式。该同位VIIRS第1级/云掩膜统计摘要（收集名称为SNDRJ2CrISL1BIMG）为主要产品，由同位CrIS视场、VIIRS云掩膜以及辐射率/反射率组成。这可以被视为CrIS与VIIRS之间的匹配。补充产品，即同位VIIRS观测值的数组索引（SNDRJ2CrISL1BIMGC），在生成IMG的过程中，提供了CrIS和VIIRS数据数组索引值，这些索引值可由终端用户利用，以进一步丰富CrIS数据，通过从任何未包含在IMG中的额外VIIRS数据产品中提取同位观测值。FSR文件包含2,223个通道（2211个衰减通道）：从3.9到4.7微米（2555到2150 cm-1）的637（633）个短波通道，从5.7到8.05微米（1752.5到1242.5 cm-1）的869（865）个中波通道，以及从9.1到15.41微米（1096.25到648.75 cm-1）的717（713）个长波通道。每个CrIS视场（FOR）包含9个视场（FOV），排列成3x3的阵列。第1B级文件在横跨轨道方向上包含30个FOR，在沿轨道方向上包含45个。数据产品在每6分钟的时间边界上构建。可见光-红外成像仪（VIIRS）拥有22个成像和辐射度波段，覆盖从0.41到12.5微米的波长。它提供了云、海面温度、海洋颜色等传感器的数据记录。此IMG_COL产品包含VIIRS像素在每个CrIS足迹内的同位索引。