The source of the data is a 1:2500000-scale map series, "Geocryological Map of Russia and Neighboring Republics", published by Russia from 1991 to 1996, which is labelled in Russian and includes a total of 16 images. In 1998, Zaitsev and others translated it into English. In this study, seven of the images were digitized: 1) Distribution of frozen and unfrozen ground, 2) Mean annual temperature of unfrozen ground at the depth of zero annual amplitude (note that there is some uncertainty because the depth of zero amplitude is not provided, and data on this parameter is generally lacking), 3) Thickness of permafrost, 4) Depth from the surface and thickness of relict permafrost, 5) Distribution of permafrost containing cryopegs, 6) Thickness of permafrost containing cryopegs, 7) Distribution of permafrost with depth.
1. The data include multiple vector layers: (1) permafrost distribution, (2) permafrost temperature, (3) permafrost thickness, (4) permafrost formation conditions, and (5) the correction image.
2. The permafrost distribution map includes the following fields: AREA, PERIMETER, FROZEN_, FROZEN_ID: POLY_, POLY_, RINGS_OK, RINGS_NOK, A, FROZEN_SOI (frozen soil layer), and temperature. FROZEN_SOI are the Chinese and English representations of the type of frozen soil, respectively.
4. Frozen soil properties:
Frozen soil
Continuous predominantly unfrozen 1-5
Continuous permafrost -3- -5
Continuous unfrozen ground 4-6
Discontinuous permafrost 0.5- -2
Predominantly continuous permafrost -1- -3
Predominantly unfrozen ground 1-3
5. Projection information:
PROJCS["Asia_North_Equidistant_Conic",
GEOGCS["GCS_North_American_1927",
DATUM["North_American_Datum_1927", SPHEROID["Clarke_1866",6378206.4,294.9786982]],
PRIMEM["Greenwich",0.0],
UNIT["Degree",0.0174532925199433]],
PROJECTION["Equidistant_Conic"],
PARAMETER["False_Easting",0.0],
PARAMETER["False_Northing",0.0],
PARAMETER["longitude_of_center",100.0],
PARAMETER["Standard_Parallel_1",15.0],
PARAMETER["Standard_Parallel_2",58.3],
PARAMETER["latitude_of_center",60.0],
UNIT["Meter",1.0]]