Verification of a new NOAA/NSIDC passive microwave sea-ice concentration climate record

Abstract

A new satellite-based passive microwave sea-ice concentration product developed for the National Oceanic and Atmospheric Administration (NOAA) Climate Data Record (CDR) programme is evaluated via comparison with other passive microwave-derived estimates. The new product leverages two well-established concentration algorithms, known as the NASA Team and Bootstrap, both developed at and produced by the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC). The sea-ice estimates compare well with similar GSFC products while also fulfilling all NOAA CDR initial operation capability (IOC) requirements, including (1) self-describing file format, (2) ISO 19115-2 compliant collection-level metadata, (3) Climate and Forecast (CF) compliant file-level metadata, (4) grid-cell level metadata (data quality fields), (5) fully automated and reproducible processing and (6) open online access to full documentation with version control, including source code and an algorithm theoretical basic document. The primary limitations of the GSFC products are lack of metadata and use of untracked manual corrections to the output fields. Smaller differences occur from minor variations in processing methods by the National Snow and Ice Data Center (for the CDR fields) and NASA (for the GSFC fields). The CDR concentrations do have some differences from the constituent GSFC concentrations, but trends and variability are not substantially different.

• Sea ice
• Arctic and Antarctic oceans
• climate data record
• evaluation
• passive microwave remote sensing.

Acknowledgements

This work was funded by NOAA's NCDC CDR programme. WNM, DJS and MHS were supported by the grant NA07OAR4310056. GP is supported by NOAA through the Cooperative Institute for Climate and Satellites—North Carolina under Cooperative Agreement NA09NES4400006. GP thanks J. Privette for beneficial suggestions and discussions on confusion matrix and K. Knapp, C. Schreck and J. Matthews for comments on the layout of the confusion matrix diagram. WNM thanks S. Mallory for initial development work on the CDR processing software. The daily and monthly NOAA/NSIDC passive microwave sea-ice concentration CDR data files, including both CDR and GSFC fields, can be downloaded from http://nsidc.org/data/g02202.html or http://www.ncdc.noaa.gov/cdr/operationalcdrs.html.