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Data Set ID:

Reconstructed North American Snow Extent, 1900-1993, Version 1

This data set contains reconstructed monthly North American snow extent values for November through March, 1900-1993. Investigators used a combination of satellite and station observations and based the reconstruction on linear regressions between the two types of observations. The data also includes standard errors of estimates as well as the observed values upon which the regressions were based.

Station-based snow observations are available for dates since the early twentieth century but lack comprehensive spatial coverage. A remotely sensed product based on visible-band imagery provides more complete spatial coverage but has only been available since the early 1970s. Since the reconstructed values are based on regression, variability is underestimated and therefore the magnitude of some extreme values is underestimated.

Data are available via FTP.

Geographic Coverage

  • Snow/Ice > Snow Cover > Snow Extent
Spatial Coverage:
  • N: 49, S: 35, E: -60, W: -125

Spatial Resolution: Not Specified
Temporal Coverage:
  • 1 December 1900 to 31 March 1993
Temporal Resolution: Not specified
Data Format(s):
  • ASCII Text
Platform(s) NOAA-4
Sensor(s): VHRR
Version: V1
Data Contributor(s): Allan Frei, David Robinson
Data Citation

As a condition of using these data, you must cite the use of this data set using the following citation. For more information, see our Use and Copyright Web page.

Frei, A. and D. Robinson. 2002. Reconstructed North American Snow Extent, 1900-1993, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: [Date Accessed].
No technical references available for this data set.
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