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Daily Ice Cover Time Series (30 years)

Introduction | Animations | Daily Grids | Daily Images | Daily Lake & River Averages


Daily Grid files were produced by linear interpolation between consecutive ice charts each winter. Grid files for a given winter (1973 -2002) and source (CIS or NIC) are compressed in a .zip file.

Daily Grids

 

 


1973 - 1979

1973cis-grids.zip
1974cis-grids.zip
1975cis-grids.zip
1976cis-grids.zip
1977cis-grids.zip
1978cis-grids.zip
1979cis-grids.zip


1980 - 1989

1980cis-grids.zip
1981cis-grids.zip
1982cis-grids.zip
1983cis-grids.zip
1984cis-grids.zip
1985cis-grids.zip
1986cis-grids.zip
1987cis-grids.zip
1988cis-grids.zip
1989cis-grids.zip
1989nic-grids.zip


1990 - 1999

1990cis-grids.zip
1990nic-grids.zip
1991cis-grids.zip
1991nic-grids.zip
1992cis-grids.zip
1992nic-grids.zip
1993cis-grids.zip
1993nic-grids.zip
1994cis-grids.zip
1994nic-grids.zip
1995cis-grids.zip
1995nic-grids.zip
1996nic-grids.zip
1997nic-grids.zip
1998nic-grids.zip
1999nic-grids.zip

 


2000 - 2002

2000nic-grids.zip
2001nic-grids.zip
2002nic-grids.zip

Zip File Name: YYYYNIC-grids.zip and YYYYCIS-grids.zip

YYYY = year (1973 - 2002), NIC = National Ice Center, CIS = Canadian Ice Service
Each .zip file has 182 Grid files. The Grid file name encodes the date and type of data: no data, interpolated data, or observed data. Grids prior to the date of the first and after the last ice chart each winter are coded zero.

Grid File Names: YYdddI.CIS and YYdddI.NIC

YY = winter season (for example, 73 for 1973, 74 for 1974,….02 for 2002)
ddd = day of the winter season (101=Dec 1, ...132=Jan 1, …282=May 31)
I = data indicator: I = 0 (no data), I = 1 (interpolated data), I = 2 (observed data)

Grid File Format: 510 records, each record has 516 "grid cells" in I2 format.

Ice Concentration Codes: -1 = land, 0 to 99 = fraction of grid cell covered by ice, expressed as a percent, 100% ice cover was coded as 99 to save room.

Coordinates: The latitude and longitude coordinate of the center of each grid cell is given in the following two fixed formatted text files: Latgrid.zip and Longrid.zip. There are 510 records in each file. The format of each record is: 516 (f 9.5,1x).

 

 
 

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