Data Set ID:

GLERL Radiation Transfer Through Freshwater Ice, Version 1

Radiation transmittance (ratio of transmitted to incident radiation) through clear ice, refrozen slush ice, and brash ice, from ice surface to ice-water interface in the 400 to 600 nanometer range (photosynthetically active range), was measured at two freshwater lakes: Silver Lake, near Ann Arbor, Michigan and Whitefish Point on Lake Superior. Data available include surface and under-ice sensor readings, date and time of observation, ice thickness, water depth, distance of under-ice sensor from ice bottom surface, and site number/location.

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Geographic Coverage

  • Snow/Ice > Ice Depth/Thickness
  • Snow/Ice > Lake Ice
  • Atmospheric Radiation > Solar Radiation
  • Atmospheric Radiation > Transmittance
Spatial Coverage:
N: 46, 
S: 42, 
E: -83, 
W: -85
Spatial Resolution:
  • Varies
Temporal Coverage:
  • 1 January 1978 to 31 December 1978
Temporal Resolution: Varies
Data Format(s):
  • ASCII Text
Version: V1
Data Contributor(s): S. Bolsenga

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.

Bolsenga, S. J. 1995. GLERL Radiation Transfer Through Freshwater Ice, Version 1. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: [Date Accessed].

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Radiation transfer through clear ice, refrozen slush, and brash ice, from the ice surface to the ice-water interface in the 400-700 nanometer range was measured at two freshwater lake sites: Silver Lake (46 degrees, 46 minutes North, 83 degrees, 43 minutes West) and Lake Superior (Whitefish Point, 46 degrees, 46 minutes North, 84 degrees, 57 minutes West). Silicon photodiodes were used to measure transmittance. The data are relevant to studying the survival of plants and animals in freshwater lakes with ice or ice and snow cover. These data were collected by the NOAA Great Lakes Environmental Research Laboratory (GLERL), Ann Arbor, MI.

Detailed Data Description


The data are in ASCII format. Table 1 describes the structure of the files.

Table 1. File Structure
Field name Position
Surface sensor reading (nanometers) 1- 4
Surface scale 5- 8
Under-ice sensor reading (nanometers) 9-12
Under-ice sensor scale 13-16
Hour 17-18
Minute 19-20
Month 21-22
Day 23-24
Year 25-26
Ice thickness (centimeters) 27-40
Water depth (centimeters)
(99=depth not measured; -1 = very deep;
other negative value = estimated depth)
Under-ice sensor depth (centimeters) 45-48
Site number 49-50
Site letter 51-51
Lake name 61-72
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File Size

The total data set is 86.8 KB.

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Sample Data Record
.3551000.315 300 930122276  24            64   0 1          SILVER LAKE         
.3601000.970 100 934122276  24            64   0 1          SILVER LAKE         
.3681000.330 300 935122276  24            64   0 1          SILVER LAKE         
.3711000.750 100 937122276  24            64 -45 1          SILVER LAKE         
.5601000.390 3001055122276  24            64   0 1          SILVER LAKE    
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References and Related Publications

Contacts and Acknowledgments

Bolsenga, S.J.


This data set is maintained at NSIDC with support from the NOAA National Geophysical Data Center.

Document Information

Document Authors

NSIDC Technical Writers

Document Creation Date


Document Revision Date

July 2017: A. Windnagel fixed the broken links in the References section.
July 2006: This document was reformatted. F. Fetterer reviewed this document.

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