Entry_ID: G02168
Entry_Title: Timing and Statistics of Autumn and Spring Annual Snow Cover for the Northern Hemisphere, 1972 to 2000
Group: Data_Set_Citation
   Dataset_Creator: Dye, D. 
   Dataset_Title: Timing and Statistics of Autumn and Spring Annual Snow Cover for the Northern Hemisphere, 1972 to 2000
   Dataset_Release_Date: 2005-12-21
   Dataset_Release_Place: Boulder, Colorado USA
   Dataset_Publisher: NSIDC: National Snow and Ice Data Center
   Online_Resource: http://nsidc.org/data/g02168.html
   Dataset DOI: http://dx.doi.org/10.7265/N5F18WNC
End_Group
Group: Personnel
   Role: Investigator
   First_Name: Dennis
   Last_Name: Dye
   Phone: 81 45-778-5594 
   Fax: 81  45-778-5706 
   Group: Contact_Address
      Address: Frontier Research Center for Global Change
      Address: Group Leader, Ecosystem Change Research Program
      City: Yokohama
      Country: Japan
   End_Group
End_Group
Group: Personnel
   Role: Investigator
   First_Name: Dennis
   Last_Name: Dye
   Phone: 81 45-778-5594 
   Fax: 81  45-778-5706 
   Group: Contact_Address
      Address: Frontier Research Center for Global Change
      Address: Group Leader, Ecosystem Change Research Program
      City: Yokohama
      Country: Japan
   End_Group
End_Group
Group: Personnel
   Role: Technical Contact
   First_Name: NSIDC
   Last_Name: User Services
   Email: nsidc@nsidc.org
   Phone: 1 303 492-6199 x
   Fax: 1 303  492-2468 x
   Group: Contact_Address
      Address: National Snow and Ice Data Center
      Address: CIRES, 449 UCB
      Address: University of Colorado
      City: Boulder
      Province_or_State: CO
      Postal_Code: 80309-0449
      Country: USA
   End_Group
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Cryosphere
   Term: Snow/Ice
   Variable_Level_1: Snow Cover
   Detailed_Variable: Duration, Timing
End_Group
Group: Parameters
   Category: EARTH SCIENCE
   Topic: Terrestrial Hydrosphere
   Term: Snow/Ice
   Variable_Level_1: Snow Cover
   Detailed_Variable: Duration, Timing
End_Group
ISO_Topic_Category: Climatology/Meteorology/Atmosphere
Keyword: NOAA
Keyword: Northern Hemisphere
Keyword: NSIDC > National Snow and Ice Data Center
Sensor_Name: AVHRR > Advanced Very High Resolution Radiometer
Sensor_Name: GOES I-M IMAGER
Sensor_Name: SSM/I > Special Sensor Microwave/Imager
Source_Name: DMSP > Defense Meteorological Satellite Program
Source_Name: GEOSTATIONARY SATELLITES
Source_Name: GROUND-BASED OBSERVATIONS
Source_Name: NOAA POES > NOAA Polar Orbiting Environmental Satellites
Source_Name: SATELLITES
Group: Temporal_Coverage
   Start_Date: 1972-01-01
   Stop_Date: 2000-12-31
End_Group
Data_Set_Progress: complete
Group: Spatial_Coverage
   Southernmost_Latitude: 0
   Northernmost_Latitude: 90
   Westernmost_Longitude: -180
   Easternmost_Longitude: 180
End_Group
Group: Location
   Location_Category: GEOGRAPHIC REGION
   Location_Type: NORTHERN HEMISPHERE
End_Group
Group: Quality

   By inspecting visible band satellite imagery, analysts from the NOAA Office of 
   Satellite Data Processing and Distribution (OSDPD), Satellite Services 
   Division (SSD), Satellite Analysis Branch (SAB), produced an analogue Northern 
   Hemisphere snow/ice map. (More recently, production of this product has taken 
   place in a digital environment. (See IMS Daily Northern Hemisphere Snow and 
   Ice Analysis at 4 km and 24 km Resolution and NOAA Operational Daily Snow 
   Cover Analysis pages at http://nsidc.org for more information.) The weekly 
   version of this product is the basis for the subject data set. Studies cited 
   in Dye (2002) note that the NOAA snow charts have limitations because they are 
   created using visible band imagery. For example, the snow cover can be 
   difficult to detect due to 'low solar illumination and high solar zenith 
   angles, dense forest cover and cloud cover'. According to Dye, these 
   limitations reduce the reliability of the data set more significantly for 
   local or regional scale studies than for global analyses.

   This study did not incorporate direct validation techniques, because there is 
   not a practical way to validate broad scale estimates of snow-covered area. 
   Instead, the author used the relationship between the snow cover cycle and the 
   snow-covered area as an alternative method for assessing validity of the data, 
   stating that 'a strong correlation between interannual fluctuations in SCA 
   [snow covered area] and WLS, WFS and DSF can provide additional confidence in 
   results from the snow-cover cycle analysis.' See Dye (2002) for more 
   information.

   The NOAA snow product has been widely used in climate studies, but it is 
   important to note that it is an operational product. That is, it is produced 
   in near real time to meet operational needs, and may have inconstancies that 
   render it unsuitable for climatological studies. Work done at the Rutgers 
   University Climate Laboratory Global Snow Lab addresses these inconsistencies.

End_Group
Data_Set_Language: English
Originating_Center: NOAA
Group: Data_Center
   Data_Center_Name: NSIDC > National Snow and Ice Data Center
   Data_Center_URL: http://nsidc.org
   Group: Personnel
      Role: Data Center Contact
      First_Name: NSIDC
      Last_Name: User Services
      Email: nsidc@nsidc.org
      Phone: 1 303 492-6199 
      Fax: 1 303  492-2468 
      Group: Contact_Address
         Address: National Snow and Ice Data Center
         Address: CIRES, 449 UCB
         Address: University of Colorado
         City: Boulder
         Province_or_State: CO
         Postal_Code: 80309-0449
         Country: USA
      End_Group
   End_Group
End_Group
Group: Data_Center
   Data_Center_Name: NOAA > National Oceanic and Atmospheric Administration
   Data_Center_URL: http://nsidc.org/noaa/
   Group: Personnel
      Role: Data Center Contact
      First_Name: NOAA
      Last_Name: User Services
      Email: nsidc@nsidc.org
      Phone: 1 303 492-6199 x
      Fax: 1 303  492-2468 x
      Group: Contact_Address
         Address: National Snow and Ice Data Center
         Address: CIRES, 449 UCB
         Address: University of Colorado
         City: Boulder
         Province_or_State: CO
         Postal_Code: 80309-0449
         Country: USA
      End_Group
   End_Group
End_Group
Group: Distribution
   Distribution_Media: FTP
   Distribution_Size: 40 KB
   Distribution_Format: Binary
End_Group
Group: Distribution
   Distribution_Media: FTP
   Distribution_Size: 951 KB
   Distribution_Format: ASCII Text (.txt)
End_Group
Group: Reference

   Dye, D.G. 2002. Variability and trends in the annual snow-cover cycle in 
   Northern Hemisphere land areas, 1972-2000. Hydrological Processes 16: 
   3065-3077.  Robinson, D.A., Dewey, K.F., and R.R. Heim Jr. 1993. Global snow 
   cover monitoring: an update. Bulletin of the American Meteorological Society 
   74: 1689-1696.

   Robinson, D.A. Frei, A. and M. C. Serreze. 1995. Recent variations and 
   regional relationships in Northern Hemisphere snow cover. Annals of Glaciology 
   21:71-76.

End_Group
Group: Summary

   The National Snow and Ice Data Center hosts a time-series data set comprising 
   annual snow cover data  for the Northern Hemisphere (covering land primarily 
   over 45 degrees North) from 1972 to 2000.  Data are presented for land areas 
   that exhibited snow cover in each of the 29 years. Variables are the  week of 
   snow disappearance, the week of snow cover onset, and the duration of the 
   snow-free period.  These variables were derived from operational NOAA weekly 
   snow cover charts that have been quality  controlled by the Rutgers University 
   Global Snow Lab. For each year of the 29-year period, there are  three binary 
   files with data in an 89 x 89 cell grid. The week of the first detected snow 
   cover in the fall  is included in the WFS file, the week of the last observed 
   snow cover in the spring is given in the WLS  file, and the duration of 
   snow-free period in weeks is given in the DSF file. Data are also provided in 
   ASCII format summary files. In addition, summary statistics for each parameter 
   are provided. These are  grids of the mean and the standard deviation for the 
   three parameters. Gridded latitude and longitude  files are also included with 
   this data set.

End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW PROJECT HOME PAGE
   End_Group
   URL: http://climate.rutgers.edu/snowcover/
   Description: Rutgers University Global Snow Lab
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/g02156.html
   Description: IMS Daily Northern Hemisphere Snow and Ice Analysis at 4 km and 24 km Resolutio
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/g02156.html
   Description: IMS Daily Northern Hemisphere Snow and Ice Analysis at 4 km and 24 km Resolution
End_Group
Group: Related_URL
   Group: URL_Content_Type
      Type: VIEW RELATED INFORMATION
   End_Group
   URL: http://nsidc.org/data/nsidc-0046.html
   Description: Northern Hemisphere EASE-Grid Weekly Snow Cover and Sea Ice Extent Version 3
End_Group
Metadata_Name: CEOS IDN DIF
Metadata_Version: 9.7
DIF_Creation_Date: 2005-12-21
Last_DIF_Revision_Date: 2014-11-19
DIF_Revision_History:  Small fix in Title. No QC needed.