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Ice concentration

General description

Technical description - Partial young ice concentration

Technical description - Partial old ice concentration

Technical description - Minimum total ice concentration

Technical description - Maximum total ice concentration

General description

These tables were prepared by Work Package 2 (Box B) as part of INSROP Phase 2 (See Working Paper no. 121). The tables include Year, Month and a number of fields with numeric names. These numbers refer to ship route segments included in the Tbl_1 shapefile set, which is a part of the dataset provided by INSROP Project I.4.2. These segments are an extract of the ship routes as defined in INSROP Working paper no. 108 (1998), prepared by Work Package 1 (Box B) as part of INSROP Phase 2.

The parameters (2 - 5) connected with ice concentration were calculated from data on total ice concentration and partial concentration of ice of different age gradations. The initial data sets were obtained by taking the values of total and partial ice concentration from the digital review (generalized for 7-10 days) ice charts (at the points corresponding to the end of each sub-segment). The charts referring to the 1953-1979 period were constructed from data of airborne and satellite ice observations. The charts of the 1990 to 1994 period were plotted from satellite observation data. In all cases data of polar stations, ships and icebreakers were taken into account.

The spatial resolution of initial data is not worse than 4 km. The error in determining the boundaries of uniform ice zones is 2 to 10 km under the normal weather conditions and up to 50 km under the unfavorable conditions. Based on airborne observations, the concentration is determined with an accuracy up to 1/10 and the age category with an accuracy up to 1 age category. If based on satellite observations the accuracy is up to 2/10 and up to 2-3 age categories, respectively.

The accuracy of presenting the ice characteristics in the digital storage formats equals 25 km for the geographical location and 0.5/10 and 1 age category for concentration.

The values of parameters for each sub-segment observed during each month of each year were derived as follows:

- parameter 2 as means of the sum of partial concentrations of new ice, nilas, young and first-year ice;

- parameter 3 as means of the sum of partial concentrations of old, second-year and multiyear ice;

- parameter 4 as a minimum value of total ice concentration;

- parameter 5 as a maximum value of total ice concentration.

Technical description - Partial young ice concentration

Technical description - Partial young ice concentration for route S by year and month

Technical description - Partial young ice concentration for route N by year and month

Technical description - Partial young ice concentration for route S by year and month

Table source file name: p02_s.txt

Path: <NSR_DATA>\icesnow\workpackage2

Table type: DText table.

* Partial young ice concentration for route S by year and month

375 records, 144 descriptive fields.

Fields: [<Name>] -- <Alias> (type of field)

[Year] -- "Year" (Numeric, no decimals)

[Month] -- "Month" (Numeric, no decimals)

[1] -- "1" (Numeric, no decimals)

...

[142] -- "142" (Numeric, no decimals)

Technical description - Partial young ice concentration for route N by year and month

Table source file name: p02_n.txt

Path: <NSR_DATA>\icesnow\workpackage2

Table type: DText table.

* Partial young ice concentration for route N by year and month

371 records, 132 descriptive fields.

Fields: [<Name>] -- <Alias> (type of field)

[Year] -- "Year" (Numeric, no decimals)

[Month] -- "Month" (Numeric, no decimals)

[201] -- "201" (Numeric, no decimals)

....

[330] -- "330" (Numeric, no decimals)

Technical description - Partial old ice concentration

Technical description - Partial old ice concentration for route S by year and month

Technical description - Partial old ice concentration for route N by year and month

Technical description - Partial old ice concentration for route S by year and month

Table source file name: p03_s.txt

Path: <NSR_DATA>\icesnow\workpackage2

Table type: DText table.

* Partial old ice concentration for route S by year and month

375 records, 144 descriptive fields.

Fields: [<Name>] -- <Alias> (type of field)

[Year] -- "Year" (Numeric, no decimals)

[Month] -- "Month" (Numeric, no decimals)

[1] -- "1" (Numeric, no decimals)

...

[142] -- "142" (Numeric, no decimals)

Technical description - Partial old ice concentration for route N by year and month

Table source file name: p03_n.txt

Path: <NSR_DATA>\icesnow\workpackage2

Table type: DText table.

* Partial old ice concentration for route N by year and month

371 records, 132 descriptive fields.

Fields: [<Name>] -- <Alias> (type of field)

[Year] -- "Year" (Numeric, no decimals)

[Month] -- "Month" (Numeric, no decimals)

[201] -- "201" (Numeric, no decimals)

....

[330] -- "330" (Numeric, no decimals)

Technical description - Minimum total ice concentration

Technical description - Minimum total ice concentration for route S by year and month

Technical description - Minimum total ice concentration for route N by year and month

Technical description - Minimum total ice concentration for route S by year and month

Table source file name: p04_s.txt

Path: <NSR_DATA>\icesnow\workpackage2

Table type: DText table.

* Minimum total ice concentration for route S by year and month

375 records, 144 descriptive fields.

Fields: [<Name>] -- <Alias> (type of field)

[Year] -- "Year" (Numeric, no decimals)

[Month] -- "Month" (Numeric, no decimals)

[1] -- "1" (Numeric, no decimals)

...

[142] -- "142" (Numeric, no decimals)

Technical description - Minimum total ice concentration for route N by year and month

Table source file name: p04_n.txt

Path: <NSR_DATA>\icesnow\workpackage2

Table type: DText table.

* Minimum total ice concentration for route N by year and month

371 records, 132 descriptive fields.

Fields: [<Name>] -- <Alias> (type of field)

[Year] -- "Year" (Numeric, no decimals)

[Month] -- "Month" (Numeric, no decimals)

[201] -- "201" (Numeric, no decimals)

....

[330] -- "330" (Numeric, no decimals)

Technical description - Maximum total ice concentration

Technical description - Maximum total ice concentration for route S by year and month

Technical description - Maximum total ice concentration for route N by year and month

Technical description - Maximum total ice concentration for route S by year and month

Table source file name: p05_s.txt

Path: <NSR_DATA>\icesnow\workpackage2

Table type: DText table.

* Maximum total ice concentration for route S by year and month

375 records, 144 descriptive fields.

Fields: [<Name>] -- <Alias> (type of field)

[Year] -- "Year" (Numeric, no decimals)

[Month] -- "Month" (Numeric, no decimals)

[1] -- "1" (Numeric, no decimals)

...

[142] -- "142" (Numeric, no decimals)

Technical description - Maximum total ice concentration for route N by year and month

Table source file name: p05_n.txt

Path: <NSR_DATA>\icesnow\workpackage2

Table type: DText table.

* Maximum total ice concentration for route N by year and month

371 records, 132 descriptive fields.

Fields: [<Name>] -- <Alias> (type of field)

[Year] -- "Year" (Numeric, no decimals)

[Month] -- "Month" (Numeric, no decimals)

[201] -- "201" (Numeric, no decimals)

....

[330] -- "330" (Numeric, no decimals)