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Great Lakes Ice Cover Data Set and Climatology Introduction Original Ice Charts First Ice, Last Ice and Ice Duration Daily Ice Cover Time Series Weekly Ice Cover Statistics Questions / Contact GLERL home  

Daily Ice Cover Time Series (30 years)

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

Map of the Great Lakes Lake Superior Lake Michigan Lake Erie Lake Ontario Lake Huron Detroit River Lake St. Clair St. Mary's River

Daily lake and river average ice cover was calculated from the daily grids. Products include Plots and Tables (ASCII text files). The plots are 5 day running averages of the daily spatial average ice concentration contained in the tables. Each plot contains one or more curves for one winter season. The lake plots for the 1989-1995 winters have two curves, one based on Canadian Ice Service (CIS) and one based on NOAA National Ice Center (NIC) ice charts. Each table contains lake or river averaged daily ice concentration. Documentation and additional analysis on Lake and river averaged ice cover will be given in a forthcoming report.

Daily Lake & River Averages: Plots and Tables


Season (all lakes plotted together for each winter season) Plots  
Great Lakes (spatial averages for all 5 Great Lakes) Plots Table (txt file)
Lake Erie Plots Table (txt file)
Lake Huron Plots Table (txt file)
Lake Michigan Plots Table (txt file)
Lake Ontario Plots Table (txt file)
Lake St. Clair Plots Table (txt file)
Lake Superior Plots Table (txt file)



Detroit River Plots Table (txt file)
St. Mary's River Plots Table (txt file)


A grid encoding the grid cells for each of these lakes and rivers is given in the following fixed formatted text file: GLmask2.txt. Each record in that file has a format of 516 I1. Land grid cells have a code of 0 or 1, the grid cell codes for each lake and river are given below.

Lake / River Code
Lake Superior 4
Lake Michigan 5
Lake Huron 6
Lake Erie 7
Lake St. Clair 2
Lake Ontario 8
St. Marys River 9
Detroit River 3

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