数据集包括：

1、permaice（冻土类型图）

2、subsea(海底界线矢量图)

3、treeline(林线矢量图)

4、nhipa(栅格图)

5、llipa(栅格图)

Permaice包括属性字段：

Num_code（冻土属性编码）

<pCombo(冻土属性）

extent（冻土范围）</p

content(含冰量）

属性对照如下：

（1）冻土属性对照表：

0 （No information ）

1 - chf （Continuous permafrost extent with high ground ice content and thick overburden）

2 - dhf （Discontinuous permafrost extent with high ground ice content and thick overburden ）

3 - shf （Sporadic permafrost extent with high ground ice content and thick overburden ）

4 - ihf （Isolated patches of permafrost extent with high ground ice content and thick overburden ）

5 - cmf （Continuous permafrost extent with medium ground ice content and thick overburden ）

6 - dmf （Discontinuous permafrost extent with medium ground ice content and thick overburden ）

7 - smf （Sporadic permafrost extent with medium ground ice content and thick overburden ）

8 - imf （Isolated patches of permafrost extent with medium ground ice content and thick overburden）

9 - clf （Continuous permafrost extent with low ground ice content and thick overburden ）

10 - dlf （Discontinuous permafrost extent with low ground ice content and thick overburden ）

11 - slf （Sporadic permafrost extent with low ground ice content and thick overburden ）

12 - ilf （Isolated patches of permafrost extent with low ground ice content and thick overburden）

13 - chr （Continuous permafrost extent with high ground ice content and thin overburden and exposed bedrock ）

14 - dhr （Discontinuous permafrost extent with high ground ice content and thin overburden and exposed bedrock ）

15 - shr （Sporadic permafrost extent with high ground ice content and thin overburden and exposed bedrock ）

16 - ihr （Isolated patches of permafrost extent with high ground ice content and thin overburden and exposed bedrock）

17 - clr （Continuous permafrost extent with low ground ice content and thin overburden and exposed bedrock ）

18 - dlr （Discontinuous permafrost extent with low ground ice content and thin overburden and exposed bedrock ）

19 - slr （Sporadic permafrost extent with low ground ice content and thin overburden and exposed bedrock）

20 - ilr （Isolated patches of permafrost extent with low ground ice content and thin overburden and exposed bedrock ）

21 - g （Glaciers）

22 - r （Relict permafrost）

23 - l （Inland lakes ）

24 - o （Ocean/inland seas ）

25 - ld （Land）

（2）冻土范围对照表

c = continuous (90-100%)

d = discontinuous (50- 90%)

s = sporadic (10- 50%)

i = isolated patches ( 0 - 10%)

（3）含冰量对照表

h = high (>20% for "f" landform codes) (>10% for "r" landform codes)

m = medium (10-20%)

l = low (0-10%)

Projection of the shapefiles is:

PROJCS["Sphere_ARC_INFO_Lambert_Azimuthal_Equal_Area",

GEOGCS["GCS_Sphere_ARC_INFO",

DATUM["Sphere_ARC_INFO", SPHEROID["Sphere_ARC_INFO",6370997.0,0.0]],

PRIMEM["Greenwich",0.0],

UNIT["Degree",0.0174532925199433]],

PROJECTION["Lambert_Azimuthal_Equal_Area"],

PARAMETER["False_Easting",0.0],

PARAMETER["False_Northing",0.0],

PARAMETER["longitude_of_center",180.0],

PARAMETER["latitude_of_center",90.0],

UNIT["Meter",1.0]]

Projection for the raster (*.byte) files is:

Projection: Lambert Azimuthal

Units: meters

Spheroid: defined

Major Axis: 6371228.00000

Minor Axis: 6371228.000

Parameters:

radius of the sphere of reference: 6371228.00000

longitude of center of projection: 0

latitude of center of projection: 90

false easting (meters): 0.00000

false northing (meters): 0.00000