Antarctic Master Directory

AVHRR Polar Pathfinder Twice-Daily 25 km EASE-Grid Composites

Federal Geographic Data Committee (FGDC) Metadata:

Identification_Information
Data_Quality_Information
Spatial_Reference_Information
Distribution_Information
Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: C. Fowler, J. Maslanik, T. Haran, T. Scambos, J. Key, and W. Emery.

Publication_Date: 20020101

Title: AVHRR Polar Pathfinder Twice-Daily 25 km EASE-Grid Composites

Edition:

Geospatial_Data_Presentation_Form:

Series_Information:

Series_Name:
Issue_Identification:

Publication_Information:

Publication_Place: Boulder, CO U.S.A.
Publisher: National Snow and Ice Data Center (NSIDC)

Other_Citation_Details:

Online_Linkage: http://nsidc.org/data/nsidc-0094.html

Description:

Abstract:: The AVHRR Polar Pathfinder Twice-Daily 25 km EASE-Grid Composites are a collection of products for both poles, consisting of twice-daily gridded and calibrated satellite channel data and derived parameters. Data include five Advanced Very High Resolution Radiometer (AVHRR) channels, clear sky surface broadband albedo and skin temperature, average albedo and temperature, valid fraction file, solar zenith angle, satellite elevation angle, sun-satellite relative azimuth angle, surface type mask, cloud mask, cloud fraction files, and Universal Coordinated Time (UTC) of acquisition. The 25-km data are derived from the AVHRR Polar Pathfinder Twice-Daily 5 km EASE-Grid Composites, and extend poleward from 48.4 degrees north and 53.2 degrees south latitudes, spanning July 1981 through December 2000. Data are in 1-byte and 2-byte integer grid format and are available by FTP. Note: NSIDC reccommends the use of the Extended AVHRR Polar Pathfinder (APP-x) Product, located at http://stratus.ssec.wisc.edu/products/appx/appx.html, instead of our AVHRR Polar Pathfinder Twice-Daily 25 km EASE-Grid Composites. The APP-x 25 km product has albedo and temperature calculations for all sky conditions. Cloud properties are modeled to estimate the albedo and temperature under the clouds. An improved cloud detection algorithm is also used in the APP-x product.
Purpose:: Not Available
Supplemental_Information:: REFERENCE: Key, J. 1999. The cloud and surface parameter retrieval (CASPR) system for polar AVHRR. Cooperative Institute for Meteorological Satellite Studies, University of Wisconsin, Madison. Key, J., J. Collins, C. Fowler, and R.S. Stone. 1997. High-latitude surface temperature estimates from thermal satellite data. Remote Sensing of the Environment 61:302-309. Kidwell, K.D. 1995. NOAA Polar Orbiter Data User's Guide, U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, NESDIS. Maslanik, J., C. Fowler, J. Key, T. Scambos, T. Hutchinson, and W. Emery, 1998. AVHRR-based Polar Pathfinder products for modeling applications. Annals of Glaciology 25:388-392. Rao, C.R.N. and J. Chen. 1999. Revised post-launch calibration of channels 1 and 2 of the Advanced Very High Resolution Radiometer on board the NOAA-14 spacecraft. http://noaasis.noaa.gov/NOAASIS/ml/aboutn14vis.html. Schweiger, A., C. Fowler, J. Key, J. Maslanik, J. Francis, R. Armstrong, M.J. Brodzik, T. Scambos, T. Haran, M. Ortmeyer, S. Khalsa, D. Rothrock, and R. Weaver. 1999. P-Cube: A multisensor data set for polar climate research. Proceedings on the 5th Conference on Polar Meteorology and Oceanography, American Meteorological Society, Dallas, TX, 15-20 Jan., 136-141.

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 19810724
Ending_Date: 20001231

Currentness_Reference:Unknown

Status:

Progress: In Work
Maintenance_and_Update_Frequency: As needed

Spatial_Domain:

Description_of_Geographic_Extent:

Bounding_Coordinates:

West_Bounding_Coordinate: -180.0
East_Bounding_Coordinate: 180.0
North_Bounding_Coordinate: -54.0
South_Bounding_Coordinate: -90.0

Spatial_Domain:

Description_of_Geographic_Extent:

Bounding_Coordinates:

West_Bounding_Coordinate: -180.0
East_Bounding_Coordinate: 180.0
North_Bounding_Coordinate: 90.0
South_Bounding_Coordinate: 48.0

Keywords:

Theme:

Theme_Keyword_Thesaurus: GCMD SCIENCE PARAMETERS
Theme_Keyword_Thesaurus: GCMD PLATFORM
Theme_Keyword_Thesaurus: GCMD INSTRUMENT
Theme_Keyword_Thesaurus: PROJECT
Theme_Keyword_Thesaurus: ANCILLARY KEYWORDS
Theme_Keyword_Thesaurus: ISO TOPIC CATEGORY
Theme_Keyword_Thesaurus: DATA SET LANGUAGE
Theme_Keyword: EARTH SCIENCE > ATMOSPHERE > CLOUDS > CLOUD PROPERTIES > CLOUD FREQUENCY
Theme_Keyword: EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC RADIATION > ALBEDO
Theme_Keyword: EARTH SCIENCE > CRYOSPHERE > SNOW/ICE > ALBEDO
Theme_Keyword: EARTH SCIENCE > TERRESTRIAL HYDROSPHERE > SNOW/ICE > ALBEDO
Theme_Keyword: EARTH SCIENCE > LAND SURFACE > LAND TEMPERATURE > LAND SURFACE TEMPERATURE
Theme_Keyword: EARTH SCIENCE > LAND SURFACE > LAND TEMPERATURE > SKIN TEMPERATURE
Theme_Keyword: EARTH SCIENCE > LAND SURFACE > SURFACE RADIATIVE PROPERTIES > ALBEDO
Theme_Keyword: EARTH SCIENCE > LAND SURFACE > SURFACE RADIATIVE PROPERTIES > THERMAL PROPERTIES
Theme_Keyword: EARTH SCIENCE > SPECTRAL/ENGINEERING > INFRARED WAVELENGTHS > INFRARED RADIANCE
Theme_Keyword: EARTH SCIENCE > SPECTRAL/ENGINEERING > INFRARED WAVELENGTHS > THERMAL INFRARED
Theme_Keyword: EARTH SCIENCE > SPECTRAL/ENGINEERING > PLATFORM CHARACTERISTICS > VIEWING GEOMETRY
Theme_Keyword: EARTH SCIENCE > SPECTRAL/ENGINEERING > VISIBLE WAVELENGTHS > VISIBLE RADIANCE
Theme_Keyword: NOAA-11 > NATIONAL OCEANIC & ATMOSPHERIC ADMINISTRATION-11
Theme_Keyword: NOAA-14 > NATIONAL OCEANIC & ATMOSPHERIC ADMINISTRATION-14
Theme_Keyword: NOAA-7 > NATIONAL OCEANIC & ATMOSPHERIC ADMINISTRATION-7
Theme_Keyword: NOAA-9 > NATIONAL OCEANIC & ATMOSPHERIC ADMINISTRATION-9
Theme_Keyword: AVHRR > ADVANCED VERY HIGH RESOLUTION RADIOMETER
Theme_Keyword: RADIOMETERS
Theme_Keyword: EOSDIS > EARTH OBSERVING SYSTEM DATA INFORMATION SYSTEM
Theme_Keyword: ESIP > EARTH SCIENCE INFORMATION PARTNERS PROGRAM
Theme_Keyword: NOAA/NASA PATHFINDER > NOAA/NASA PATHFINDER PROGRAM
Theme_Keyword: Antarctic
Theme_Keyword: Arctic
Theme_Keyword: Avhrr
Theme_Keyword: Cryosphere
Theme_Keyword: Daac
Theme_Keyword: Eosdis
Theme_Keyword: Nasa
Theme_Keyword: Noaa
Theme_Keyword: Nsidc
Theme_Keyword: Pathfinder
Theme_Keyword: Polar
Theme_Keyword: Radiance
Theme_Keyword: Remote Sensing
Theme_Keyword: Satellite
Theme_Keyword: CLIMATOLOGY/METEOROLOGY/ATMOSPHERE
Theme_Keyword: GEOSCIENTIFIC INFORMATION
Theme_Keyword: IMAGERY/BASE MAPS/EARTH COVER
Theme_Keyword: INLAND WATERS
Theme_Keyword: ENGLISH

Place:

Place_Keyword_Thesaurus: GCMD
Place_Keyword: CONTINENT > ANTARCTICA
Place_Keyword: GEOGRAPHIC REGION > ARCTIC
Place_Keyword: GEOGRAPHIC REGION > POLAR

Temporal:

Temporal_Keyword_Thesaurus: GCMD
Temporal_Keyword: Twice-daily

Access_Constraints: Not Available

Use_Constraints:

Not Available

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: NSIDC USER SERVICES

Contact_Position: TECHNICAL CONTACT

Contact_Address:

Address_Type: Mailing and Physical Address
Address: National Snow and Ice Data Center
Address: CIRES, 449 UCB
Address: University of Colorado
City: Boulder
State_or_Province: CO
Postal_Code: 80309-0449
Country: USA

Contact_Voice_Telephone: +1 (303) 492-6199

Contact_Facsimile_Telephone: +1 (303) 492-2468

Contact_Electronic_Mail_Address: nsidc@nsidc.org

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:: Channel data are accurate to within approximately +/- 0.2 percent based on sensor noise level of 0.4 data number (DN). Temperatures are accurate to within approximately 2 degrees Kelvin. Relative albedos in adjacent grid cells are accurate to within approximately 5 percent. However, absolute albedo values are approximate. Accuracies for the products are difficult to determine, given the limited nature of existing case studies. Also, conditions vary substantially across the large product domains and over time. Plans are being developed to further define product accuracies for snow-covered areas, sea ice, and ice sheets. Based on studies to date, accuracies in general are approximately +/- 2 degrees Kelvin for AVHRR-derived skin temperatures and +/- 0.05 degrees for surface albedo. Much of this error is likely due to uncertainties in the performance of the cloud detection methods. For clear sky conditions, accuracies for albedo and temperature products are expected to be in the range noted in the Barrow test, with temperatures accurate to +/- 0.5 degrees Celsius. Data and related information will be updated as appropriate. Additional comparisons with in-situ measurements of albedo and temperature are planned. See also Maslanik et al. (2000) for other accuracy discussions relative to SHEBA data.

Logical_Consistency_Report:

Not Available

Completeness_Report:

Not Available

Lineage:

Process_Step:

Process_Description:: Not Available
Process_Date: Unknown

Spatial_Reference_Information:

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: NSIDC_DAAC > NSIDC Distributed Active Archive Center
Contact_Person: NSIDC USER SERVICES

Contact_Position: DATA CENTER CONTACT

Contact_Address:

Address_Type: Mailing and Physical Address
Address: National Snow and Ice Data Center
Address: CIRES, 449 UCB
Address: University of Colorado
City: Boulder
State_or_Province: CO
Postal_Code: 80309-0449
Country: USA

Contact_Voice_Telephone: +1 (303) 492-6199

Contact_Facsimile_Telephone: +1 (303) 492-2468

Contact_Electronic_Mail_Address: nsidc@nsidc.org

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: NSIDC > National Snow and Ice Data Center
Contact_Person: NSIDC USER SERVICES

Contact_Position: DATA CENTER CONTACT

Contact_Address:

Address_Type: Mailing and Physical Address
Address: National Snow and Ice Data Center
Address: CIRES, 449 UCB
Address: University of Colorado
City: Boulder
State_or_Province: CO
Postal_Code: 80309-0449
Country: USA

Contact_Voice_Telephone: +1 (303) 492-6199

Contact_Facsimile_Telephone: +1 (303) 492-2468

Contact_Electronic_Mail_Address: nsidc@nsidc.org

Resource_Description: NSIDC-0094

Distribution_Liability:

Not Available

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: 1-byte and 2-byte integer grids
Transfer_Size: North: 230,642 bytes (2-byte grid) and 130,321 bytes

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name:: http://nsidc.org/daac/index.html

Access_Instructions:

DATA CENTER URL

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name:: http://nsidc.org

Access_Instructions:

DATA CENTER URL

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name:: http://reverb.echo.nasa.gov/reverb/#utf8=%E2%9C%93...

Access_Instructions:

Refine your granule search with ECHO's next generation Earth Science discovery tool (Reverb) using information from this record.

Fees: Not Available

Metadata_Reference_Information:

Metadata_Date: 20020306

Metadata_Review_Date: 20120514

Metadata_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Person: GCMD User Support Office
Contact_Organization: NASA Global Change Master Directory

Contact_Address:

Address_Type: Mailing and Physical Address
Address: Not Available
City: Lanham
State_or_Province: MD
Postal_Code: 20706
Country: USA

Contact_Voice_Telephone: Not Available

Contact_Electronic_Mail_Address: gcmduso@gcmd.gsfc.nasa.gov

Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Time_Convention: local time