Timing and Statistics of Autumn and Spring Annual Snow Cover for the Northern Hemisphere  View Catalog Page Entry ID
G02168
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.
Geographic Coverage
Spatial Coordinates:
N: 90°
S: 0°
E: 180°
W: -180°
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Data Set Citation
Dataset Creator: Dennis Dye
Dataset Title: Timing and Statistics of Autumn and Spring Annual Snow Cover for the Northern Hemisphere
Dataset Release Date: 2005-12-21
Dataset Release Place: Boulder, CO
Dataset Publisher: National Snow and Ice Data Center (NSIDC)
Data Presentation Form: Digital media
Online Resource: http://nsidc.org/data/g02168.html
Temporal Coverage
Start Date: 1972-01-01
Stop Date: 2000-12-31
Location Keywords
- Geographic Region Northern Hemisphere
Science Keywords
- Cryosphere Snow/Ice Snow Cover DURATION, TIMING
- Terrestrial Hydrosphere Snow/Ice Snow Cover DURATION, TIMING
Ancillary Keywords
- NOAA
- Northern Hemisphere
- NSIDC > National Snow and Ice Data Center
- Climatology/Meteorology/Atmosphere
Platform
- GROUND-BASED OBSERVATIONS
- SATELLITES
Instrument
- AVHRR Advanced Very High Resolution Radiometer
- GOES I-M IMAGER
- SSM/I Special Sensor Microwave/Imager
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.
Data Set Progress
COMPLETE
Originating Center
NSIDC_NOAA
Data Center
NSIDC National Oceanic and Atmospheric Administration
Data Center URL: http://nsidc.org/noaa/
Data Set ID: g02168
Data Center Personnel
Name: NSIDC NOAA User Services
Phone: +1 (303) 492-6199
Fax: +1 (303) 492-2468
Email: nsidc@nsidc.org
Contact Address:
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
City: Boulder
Province or State: CO
Postal Code: 80309-0449
Country: USA
Distribution
Distribution Media: FTP
Distribution Size: 40 KB
Distribution Format: binary
Distribution Media: FTP
Distribution Size: 951 KB
Distribution Format: ASCII text
Personnel
Dennis Dye
Role: INVESTIGATOR
Phone: +81-45-778-5594
Fax: +81-45-778-5706
Contact Address:
City: Yokohama
Country: Japan
NSIDC User Services
Role: TECHNICAL CONTACT
Phone: (303) 492-6199
Fax: (303) 492-2468
Email: nsidc@nsidc.org
Contact Address:
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
City: Boulder
Province or State: CO
Postal Code: 80309-0449
Country: USA
Related URL
VIEW RELATED INFORMATION
Rutgers University Global Snow Lab
VIEW RELATED INFORMATION
IMS Daily Northern Hemisphere Snow and Ice Analysis at 4 km and 24 km Resolutio
VIEW RELATED INFORMATION
Northern Hemisphere EASE-Grid Weekly Snow Cover and Sea Ice Extent Version 3
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.
Metadata Name and Version
Metadata Name: CEOS IDN DIF
Metadata Version: 9.7
Creation and Review Dates
DIF Creation Date: 2005-12-20
Last DIF Revision Date: 2007-08-21
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