Polar Pathfinder Sampler: AVHRR, SMMR-SSM/I, and TOVS Samples and Combined Time Series

Data Contributors

ARMSTRONG, RICHARD
EMERY, WILLIAM
FOWLER, CHUCK
FRANCIS, JENNIFER A.
HARAN, TERRY
KEY, JEFFREY
KHALSA, SIRI JODHA SINGH
MASLANIK, JIM
SCAMBOS, TED
SCHWEIGER, AXEL J.

Parameters

AIR TEMPERATURE
ALBEDO
BRIGHTNESS TEMPERATURE
CLOUD AMOUNT/FREQUENCY > EFFECTIVE CLOUD FRACTION
CLOUD TOP PRESSURE
CLOUD TOP TEMPERATURE
EMISSIVITY
INFRARED IMAGERY
PRECIPITABLE WATER
SEA ICE CONCENTRATION
SEA ICE MOTION
SKIN TEMPERATURE
SNOW/ICE TEMPERATURE
THERMAL INFRARED
VISIBLE IMAGERY
WIND STRESS > GEOSTROPHIC DRAG COEFFICIENT, TURNING ANGLE

Instruments

AVHRR : ADVANCED VERY HIGH RESOLUTION RADIOMETER
SMMR : SCANNING MULTICHANNEL MICROWAVE RADIOMETER
SSM/I : SPECIAL SENSOR MICROWAVE/IMAGER
TOVS : TIROS OPERATIONAL VERTICAL SOUNDER

The AVHRR, SMMR-SSM/I and TOVS Polar Pathfinder research teams collaborated to make it as easy as possible to use Polar Pathfinder data sets together by employing a common projection, namely the NSIDC Equal-Area Scalable Earth-Grid (EASE-Grid), and validation methods to develop consistently processed data sets that are easy to combine, compare and contrast. This CD-ROM includes sample data, time-series visualizations, and browse products, for temporal and spatial subsets of the AVHRR, SMMR-SSM/I and TOVS data sets, to illustrate the types of products available for the various data sets.

AVHRR products for both hemispheres, at 1.25 and 5 km resolutions, include calibrated channel data, surface broadband albedo, surface temperature, and ancillary data so that users can apply algorithms of their choice to calculate albedo and surface temperature. To conserve space, the CD-ROM includes 1.25 km AVHRR time-series visualizations, rather than raw data; and 5 km AVHRR sample data (for 8 September 1997), movies and browse images. SMMR-SSM/I parameters, that can be derived from global brightness temperatures, include snow water equivalent, snow extent, seasonal sea ice concentrations, location of multiyear ice, ocean wind speed, cloud liquid water over oceans and water vapor over oceans. The CD-ROM contains a sample data set comprising selected SSM/I brightness temperature data and time files for 8 September 1997 (the same day as in the 5 km AVHRR data, to facilitate comparisons) in each of three projections: Northern and Southern Hemispheres and a global projection. TOVS parameters derived from arctic radiances include atmospheric temperature profiles, water vapor, surface temperature, total effective cloud fraction, cloud top pressure and temperature, turning angle between geostrophic wind and surface stress over ice, emissivity, boundary layer stratification and geostrophic drag coefficient. The CD-ROM includes sample TOVS products for four selected dates in 1988.

The P-Cube is a multidimensional structure combining arctic SSM/I, AVHRR and TOVS data, all mapped to a 100 km resolution EASE-Grid, thereby facilitating study of polar processes and interactions among them using data from multiple sensors. The current prototype version of the P-Cube includes the most important parameters from the three Polar Pathfinders noted above. The Polar Pathfinder Sampler CD-ROM is currently the only source of the P-Cube data; temporal coverage extends from 1 January 1988 to 31 December 1989.

All data at the original resolution are now available. See NOAA/NASA Polar Pathfinder Data or contact User Services for more information.

Data Citation

National Snow and Ice Data Center, compiler. 1999. Polar Pathfinder sampler: AVHRR, SMMR-SSM/I, and TOVS samples and combined time series. Boulder, CO: National Snow and Ice Data Center. CD-ROM.