The Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS Passive Microwave Data, Version 1 data set, accessible from the NASA National Snow and Ice Data Center Distributed Active Archive Center (NSIDC DAAC), has been updated through 31 May 2021. This data set is generated from brightness temperature data and is designed to provide a consistent time series of sea ice concentrations spanning the coverage of several passive microwave instruments. The data are provided in the polar stereographic projection at a grid cell size of 25 x 25 km.
Data set DOI: https://doi.org/10.5067/8GQ8LZQVL0VL