MODIS/Aqua Clear Radiance Statistics Indexed to Global Grid 5-Min L2 Swath 10km

The MODIS/Aqua Clear Radiance Statistics Indexed to Global Grid 5-Min L2 Swath 10km (MYDCSR_G)product provides a variety of, statistical measures that characterize observed top-of-atmosphere clear sky radiances at a 10 km spatial resolution. Clear radiances are collected for all earth scenes and separated by day and night.

The MYDCSR_G serves as input to the downstream Level 3 aggregation processes that culminate with the production of the 1-degree Zonal Bias Product (MYDCSR_B) used as input to PGE06 (MODIS Cloud Product).

MYDCSR_G data are collected for bands 1-7 and 17-36 for all but the last two statistics. Calculated clear-sky radiances are produced for bands 20, 22-25, and 27-36 and subtracted from observed values. Differences in bands 31 and 33-36 are summed and used to create the clear-sky biases used in generating the PGE06 cloud top pressure field. Numbers of observations from land vs. water are also kept for each 25-km region. Biases are used to quantify the difference between instrument observed radiances and a calculated radiance. This difference is especially important for the cloud top properties retrieval which utilizes an atmospheric transmittance model as a means of calculating radiances in different layers of the atmosphere and matching that to observations.

The biases contained in MYDCSR_G are the difference between the calculated radiance and the observed radiance for all clear-sky grid cells which fall within the given granule. The MYDCSR_G files are in Hierarchical Data Format (HDF).