Data Announcement
  • Sea ice

Sea Ice Concentration CDR Updated to Version 3 and a Near-Real-Time Version Released

NOAA@NSIDC is pleased to announce the release of Version 3 of the NOAA/NSIDC Climate Data Record of Passive Microwave Sea Ice Concentration (final CDR). The reason for the version change is to update the masks used to remove spurious ice in the Northern Hemisphere. The masks changed from sea surface temperature climatology-based masks to the Polar Stereographic Valid Ice Masks Derived from National Ice Center Monthly Sea Ice Climatologies. These masks are used for most passive microwave-based sea ice products at NSIDC. In addition, a Near-Real-Time NOAA/NSIDC Climate Data Record of Passive Microwave Sea Ice Concentration (NRT CDR) has been released. The NRT CDR fills the temporal gap between updates of the final CDR, occurring annually, and provides the most recent available data. The NRT CDR uses a different brightness temperature input data source for the sea ice concentration algorithm. It omits the three NASA Goddard concentration variables from the product. Unlike the final CDR, which incorporates data sets with more stringent quality control measures, the NRT CDR includes only preliminary processing without final QC, and should be used with caution. The NOAA/NSIDC Sea Ice Concentration CDR uses both the NASA Team and the NASA Bootstrap passive microwave algorithms and combines them in a way that capitalizes on their strengths. The NRT CDR answers a need for ice concentration fields that are updated every day and are generally more reliable than those available from data products that use only the NASA Team or only the Bootstrap algorithm. To learn more about these updates and to access the data, visit the data set landing pages for each product: This work is supported by the NOAA Climate Data Record program and by NOAA NCEI support to NOAA@NSIDC.