PACE Mission ▸ Similated and Proxy Data

Simulated and Proxy Data

For OCI, simulated data at Level-1B is being generated to support processing software development and testing. Simulated Level-1C data has been produced for SPEXone, and there is a SPEX airborne instrument that provides valuable proxy data for testing algorithms. Proxy data is also available for HARP2, including data from an airborne version, and the HARP cubesat that began operations in April 2020.

OCI Level-1B

Several simulators have been developed to produce OCI Level-1B data.

  • pyTOAST Simulation

    The python top-of-atmosphere simulation tool (pyTOAST) utilizes retrieved surface and atmospheric properties and top-of-atmosphere (TOA) radiances from MODIS and VIIRS, pre-computed radiative-transfer look-up tables for the OCI spectral response, and spectral libraries of land and clouds to produce realistic radiometry in the standard Level-1B format of OCI. The pyTOAST simulator is computationally efficient, and thus allows for large scale production for testing retrieval software mechanics and data flow. OCI Level-1B pyTOAST data is available for a 5-day period from 21-25 March 2019. Read more...

  • GMAO Simulation (coming soon)

SPEXone Level-1C

  • SPEXone Simulated Data

    The SPEXone instrument team from SRON has developed a set of simulated SPEXone Level-1C orbits, following the data format and naming conventions anticipated for the PACE mission. The data is based on vector radiative transfer simulations using surface and atmospheric input fields from POLDER and MODIS retrievals and the ECHAM-HAM model. The dataset includes 15 orbits spanning one day (15 July 2017), and also includes the auxiliary data (meterological and environmental assumptions) and truth data (geophysical fields) used to generate the Level-1C. This data is being made available to support SPEXone geophysical retrieval algorithm development and pre-launch science software implementation and testing. Read more...

  • SPEX Airborne Proxy Data (ACEPOL data description paper)

HARP2 Level-1C

RSP Level-1C

The Research Scanning Polarimeter (RSP) is an airborne multi-angle polarimeter which can serve as a proxy for HARP-2 and SPEXone datasets for the purposes of algorithm development and testing. RSP uses a polarization compensated scanning mirror assembly to make highly accurate measurements at a maximum of 152 viewing angles and in nine spectral channels in the VIS and SWIR. Note that RSP is not an imager, but scans along the aircraft track. RSP has been deployed in many field campaigns over the last two decades, including alongside the SPEX Airborne and Air HARP instruments in the Aerosol Characterization from Lidar and Polarimeter (ACEPOL) field campaign. Data are available in a format corresponding to that of PACE L1C, without spatial gridding. Data in this format will be made available for campaigns other than ACEPOL in the future. Please contact the RSP team for data set requests. Please read the README.txt file for more information about this data. Other RSP data and more information can be found here.

RSP archive for PACE: https://data.giss.nasa.gov/pub/rsp/data/PACE/