-------------------------------------------------------------------------------- (1.) GENERAL DATASET INFORMATION -------------------------------------------------------------------------------- SPATIAL RESOLUTION: 6km x 6km DATA FORMAT: Binary SPATIAL PROJECTION: Polar EASE-Grid (Version 2) format (3000 columns and 3000 rows consisting of 8-bit byte) for the Northern/Southern Hemisphere TEMPORAL EXTENT: June 2 2002 - October 4 2011 and July 23 2012 - December 31 2021 SPATIAL EXTENT: Northern Hemisphere and Southern Hemisphere Sensors: Calibrated AMSR2 Brightness Temperatures (Tb) used (Du et al., 2014) -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- (2.) EASE-Grid (version 2) format information -------------------------------------------------------------------------------- http://nsidc.org/data/ease/ease_grid2.html -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- (3.) Naming convention -------------------------------------------------------------------------------- [InstrumentLabel]_[Channel][Polarization]_[OverpassCode]_FT_[Year]_day[DOY]_[Hemisphere]_06km.bin [InstrumentLabel]= AMSR [Channel]= 36.5GHz [Polarization]=veritcal polarization [OverpassCode]=AM (AM overpass), PM (PM overpass), CO (composited at daily intervals to define Frozen (AM & PM), Non-Frozen (AM & PM), Transitional (AM frozen; PM thawed) and Inverse-Transitional (AM thawed; PM frozen) states [Hemisphere]=NH (Northern Hemisphere), SH (Southern Hemisphere) -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- (4.) FT classification -------------------------------------------------------------------------------- Frozen (AM/PM frozen): FT DN=0 Thawed (AM/PM thawed): FT DN=1 Transitional (AM frozen and PM thawed): FT DN=2 Inverse Transitional (AM thawed and PM frozen): FT DN=3 No FT data available: FT DN=252 Non-cold constraint area: FT DN=253 100% open water: FT DN=254 Fill value: FT DN=255 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- (5.) MAIN REFERENCES -------------------------------------------------------------------------------- FT algorithms Kim, Y., J. S. Kimball, J. Glassy, and J. Du. 2017. An extended global earth system data record on daily landscape freeze-thaw status determined from satellite passivie microwave remote sensing. Earth System Science Data, 9, 133-147 Calibrated Brightness Temperatures (Tb) Du, J., Kimball, J.S., Shi, J., Jones, L.A., Wu, S., Sun, R., Yang, H. 2014. Inter-Calibration of Satellite Passive Microwave Land Observations from AMSR-E and AMSR2 Using Overlapping FY3B-MWRI Sensor Measurements. Remote Sensing, 6, 8594-8616. -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- (6.) Contacts -------------------------------------------------------------------------------- Dr. John S. Kimball (johnk@ntsg.umt.edu) Dr. Youngwook Kim (youngwook.kim@ntsg.umt.edu) -------------------------------------------------------------------------------- (7.) Notes -------------------------------------------------------------------------------- These datasets were released on 2021-08-30 and updated on 2022-08-23 and 2023-04-05 --------------------------------------------------------------------------------