The University of Wisconsin-Madison SSEC is pleased to announce a new Community Satellite Processing Package (CSPP) software release that supports NOAA VIIRS Surface Reflectances in support of the NOAA-20 and S-NPP direct broadcast community. Surface reflectances differ from Top-Of-Atmosphere (TOA) reflectances in that they are corrected to remove the influence of the atmosphere, thereby preserving only the portion that is being reflected from the surface below.
This VIIRS software package contains binary executable files and supporting static data files, as well as input and output files for verification of a correct local installation. The CSPP software (CSPP_LSR Version 1.0) provides NOAA VIIRS Surface Reflectance Version 1.2, adapted and tested for operation in a real-time direct broadcast environment. A separate test data package can be downloaded for verifying a successful installation.
In addition, the Surface Reflectances are then used to create Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) products. These retrievals are not created using official NOAA/NESDIS/STAR software, which produces the Vegetation Indices on a multi-day global grid, but are created for each pixel in the input swath at 375m resolution.
The JPSS program worked with the CSPP team to integrate the JPSS processing framework enterprise algorithms into stand alone executables, which can then be run through simple CSPP bash shell and python scripts. The output Land Surface Reflectance product created by this software is identical in naming, format (NetCDF), and structure to the corresponding NPP Data Exploitation system (NDE) files.
The CSPP VIIRS Surface Reflectance software supports the following products:
- VIIRS Surface Reflectances for the following bands:
I-Bands 1, 2 and 3,
M-Bands 1,2,3,4,5,7,8,10 and 11.
VIIRS swath based Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (VI).
- Daytime VIIRS Sensor Data Records (SDRs),
Daytime CSPP VIIRS ASCI Cloud Mask, Cloud Height, Aerosol, and Gridded NWP EDRs. The ASCI software is also part of the CSPP software suite (https://cimss.ssec.wisc.edu/cspp/viirs_asci_v1.1.shtml).
- Easy execution through a main bash shell script, CSPP_VIIRS_Surface_Reflectance.sh,
No dynamic ancillary data inputs are required,
VIIRS Land Surface Reflectance software in this release is designed to work with VIIRS SDRs created by CSPP SDR v3.2 and higher, and CSPP ASCI Version 1.1 and higher,
Inputs are VIIRS SDRs and a subset of CSPP VIIRS ASCI EDRs,
Multi-core processing is supported (-p option).
- Intel or AMD CPU with 64-bit instruction support,
1 GB RAM (minimum) per core,
CentOS-7 64-bit Linux (or other compatible 64-bit Linux distribution),
perl v5.010 or above,
2.5 GB disk space (minimum), plus 5 GB for verification data.
The CSPP Team is working on support for creating Surface Reflectance and Vegetation Index images using the CSPP Polar2Grid (P2G) visualization software. We expect to distribute the P2G update in the next 1-2 months. When this happens, we will make an announcement to CSPP registrants, and also update the documentation with instructions on how to make high resolution cloud cleared images.
Nick Bearson leads the CSPP VIIRS Surface Reflectance software development at the Space Science and Engineering Center located at the University of Wisconsin-Madison with funding support from the NOAA/NASA Joint Polar Satellite System (JPSS).
The software, test data and installation guide are available at the CSPP Download website.