Geocryology and Geocryological Zonation of Mongolia

Summary

The map of Geocryology and Geocryological Zonation of Mongolia was digitized from the National Atlas of Mongolia (Sodnom and Yanshin, 1990). The data set depicts the distribution and general properties of permafrost and seasonally frozen ground and locations of specific cryogenic phenomena in Mongolia. Two plates were digitized. One plate, at a scale of 1:12,000,000, depicts four general geocryological zones: continuous and discontinuous permafrost, insular and sparsely insular permafrost, sporadic permafrost, and seasonally frozen ground. The second plate, at a scale of 1:4,500,000, depicts 14 different terrain classifications determined according to elevation, mean annual air temperature, permafrost thickness and thaw depth, and seasonal frozen ground freeze depth. The locations of six specific cryogenic phenomena are also included: perennial frost mounds, icings, thermokarst, cryogenic landslides, solifluction, and cryogenic planation. Data are available via FTP as ESRI shapefiles.

Citing These Data

Sodnom, N. and A. L. Yanshin, eds. 1990. Geocryology and geocryological zonation of Mongolia. Digitized 2005 by M. A. Parsons. Boulder, CO: National Snow and Ice Data Center. Digital Media.

Overview Table

Category	Description
Data format	ESRI Shapefiles
Spatial coverage	Mongolia (87.0°E - 121.4°E, 40.6°N - 52.2°N). Digitized from 1:4,500,000 and 1:12,000,000 maps.
Projection	Albus Equal Area-Conic Central Meridian: 103.833 degrees Origin Latitude: 46.867 degrees Standard Parallel 1: 43.342 degrees Standard Parallel 2: 50.383 degrees
File naming convention	ESRI shapefiles in the general format as follows: *.dbf = attribute data *.prj = projection information *.shp = feature geometry *.shp.xml = ESRI/FGDC formatted metadata (This file is optional and does not include all the information in this document) *.shx = the shape index, which stores an index to the feature geometry *.sbx, *.sbn = spatial index of the features
File size	11 ESRI shapefiles consisting of 79 actual files total 1.6 MB. Individual files sizes range from from 2 KB to 1 MB.
Parameters	freeze depth icings mean annual air temperature perennial frost mounds permafrost distribution permafrost thickness seasonal frozen ground solifluction thaw depth thermokarst
Procedures for obtaining data	Data are available via FTP.

Table of Contents

1. Contacts and Acknowledgments
2. Detailed Data Description
3. Data Access and Tools
4. Data Acquisition and Processing
5. References and Related Publications
6. Document Information

1. Contacts and Acknowledgments

Technical Contact

Acknowledgements

This work was supported by the International Arctic Research Center, University of Alaska Fairbanks, under the U.S. NSF cooperative agreement OPP-0327664.

2. Detailed Data Description

File Format and Naming Convention

Files are in ESRI shapefile format. A shapefile consists of several actual files that are usually considered as one file by most GIS applications. The following file types are included:

*.dbf = attribute data
*.prj = projection information
*.shp = feature geometry
*.shp.xml = ESRI/FGDC formatted metadata (This file is optional and does not include all the information in this document)
*.shx = the shape index, which stores an index to the feature geometry
*.sbx, *.sbn = spatial index of the features

The data set consists of the following shapefiles:

cryo_landslide.shp = point locations of cryogenic landslides
cryo_planation.shp = point locations of cryogenic planation
dig_country_bnd.shp = digitized country boundary polygon from the 1:4,500,000 map
dig_lakes.shp = digitized lake polygons from the 1:4,500,000 map
dig_streams.shp = digitized stream vectors from the 1:4,500,000 map
geocryo_regions.shp = digitized geocryological region polygons from the 1:12,000,000 map. See the attribute description below.
geocryology.shp = digitized polygons of areas with detailed geocryological information from the 1:4,500,000 map. See the attribute description below.
icings.shp = point locations of icings
per_frost_mound.shp = point locations of perennial frost mounds
solifluction.shp = point locations of solifluction
thermokarst.shp = point locations of thermokarst

File Size

11 ESRI shapefiles consisting of 79 actual files total 1.6 MB. Individual files sizes range from from 2 KB to 1 MB.

Spatial Coverage

Mongolia

Southernmost Latitude: 40.608° N
Northernmost Latitude: 52.230° N
Westernmost Longitude: 87.002° E
Easternmost Longitude: 121.355° E

Projection

Albus Equal Area-Conic
Central Meridian: 103.833 degrees
Origin Latitude: 46.867 degrees
Standard Parallel 1: 43.342 degrees
Standard Parallel 2: 50.383 degrees

Parameters and Attributes

Parameters include the locations of thermokarst, icings, perennial frost mounds cryogenic landslides, solifluction, and cryogenic planation. The geocryo_regions.shp file shows the location of four geocryological regions: continuous and discontinuous permafrost, insular and sparsely insular permafrost, sporadic permafrost, and seasonal frozen ground. These regions are labeled in the shapefile attribute table. This classification scheme is not defined. It is unclear how it relates to the International Permafrost Association definitions for permafrost regions. The geocryology.shp file includes a more detailed 14-level classification scheme shown in the table below. The values in the table are included in the attribute table of the shapefile.

Value	Terrain	General Landform	Thaw Depth (m)	Freeze Depth (m)	Mean Annual Air Temperature (°C)	Prevalent Permafrost Thickness (m)
1	permafrost ("pf")	slopes and watersheds ("hi")	1.0 - 3.5	-	-2 - -5	> 100 ("3")
2	permafrost ("pf")	slopes and watersheds ("hi")	1.5 - 4.5	-	0 - -2	< 100 ("2")
3	permafrost ("pf")	valley bottoms and basins ("lo")	1.3 - 2.5	-	-2 - -5	> 100 ("3")
4	permafrost ("pf")	valley bottoms and basins ("lo")	1.5 - 4.0	-	0 - -2	< 100 ("2")
5	permafrost ("pf")	valley bottoms and basins ("lo")	1.7 - 3.0	-	0 - -1	< 50 ("1")
6	seasonal frozen ground ("sfg")	slopes and watersheds ("hi")	-	3.0 - 4.5	0 - +2	-
7	seasonal frozen ground ("sfg")	slopes and watersheds ("hi")	-	2.5 - 4.5	0 - +3	-
8	seasonal frozen ground ("sfg")	slopes and watersheds ("hi")	-	2.0 - 4.1	+2 - +5	-
9	seasonal frozen ground ("sfg")	slopes and watersheds ("hi")	-	2.0 - 4.0	+3 - +10	-
10	seasonal frozen ground ("sfg")	valley bottoms and basins ("lo")	-	2.5 - 5.0	0 - +2	-
11	seasonal frozen ground ("sfg")	valley bottoms and basins ("lo")	-	2.2 - 5.0	0 - +3	-
12	seasonal frozen ground ("sfg")	valley bottoms and basins ("lo")	-	1.6 - 4.5	+2 - +5	-
13	seasonal frozen ground ("sfg")	valley bottoms and basins ("lo")	-	2.0 - 4.5	+3 - +10	-
14	seasonal frozen ground ("sfg")	valley bottoms and basins ("lo")	-	2.5 - 4.0	+5 - +10	-

Sample Images

These figures show examples of geocryology.shp and geocryo_regions.shp using a color scheme that approximates that used in the original paper maps. Click on the image for a larger version.

geocryology.shp

geocryo_regions.shp

Errors and Uncertainty

The original published atlas (Sodnom and Yanshin 1990) included the following table with the maps.

High altitude geocryological zones	Altitude (m)	Area (sq km)	% of Mongolia
continuous & discontinuous permafrost terrains	1200-2800	175,280	11.2
insular and sparsely insular permafrost terrains	700-2600	350,560	22.4
sporadic permafrost terrains	600-1900	460,110	29.4
seasonally frozen terrains	600-1800	579,050	37.0

An analysis of the digital versions of the maps produces different percentages that can vary as much as two percentage points depending on whether lake area is included in the analysis. Furthermore, Sodnom and Yanshin's table gives the total area of Mongolia as 1,565,000 km² while the calculated area of geocryo_regions.shp is 1,611,023 km². The World Factbook (CIA 2005) lists the area of Mongolia as 1,564,116 km² and the Digital Chart of the World (ESRI 1992) indicates 1,565,866 km². Some error was inevitably introduced as part of the digitization process. The lack of information of how the original maps were produced and how the regions are defined adds additional uncertainty. This data set is best used for broad scale analysis and comparisons and is unsuitable for very fine scale spatial analysis.

3. Data Access and Tools

Data Access

Data are available via FTP.

Volume

The entire data set is 1.6 MB.

Software and Tools

Geographic Information Systems such as ESRI's ArcGIS or the Geographic Resources Analysis Support System (GRASS) are most suitable for analyzing these data.

Related Data Collections

• Circum-Arctic Map of Permafrost and Ground Ice Conditions

4. Data Acquisition and Processing

Data Acquisition Methods

The maps were digitized by first scanning the images at high resolution and then rectifying the image to the Digital Chart of the World's boundary map of Mongolia (ESRI 2005). No projection information was available on the original map, so the projection was chosen to best rectify the map.

Data Source

Sodnom, N. and A. L. Yanshin, eds. 1990. Geocryology and Geocryological Zonation, in the National Atlas of Mongolia. Ulan Bator, Mongolia/Moscow: GUGK. Plates 40 and 41, scale 1:4,500,000

5. References and Related Publications

CIA (Central Intelligence Agency). 2005. The World Factbook. Accessed 7 September 2005 at http://www.cia.gov/cia/publications/factbook/index.html

ESRI (Environmental Systems Research Institute). 1992. Digital Chart of the World. Redlands, CA: Environmental Systems Research Institute.

Sodnom, N. and A. L. Yanshin, eds. 1990. Geocryology and Geocryological Zonation, in the National Atlas of Mongolia. Ulan Bator, Mongolia/Moscow: GUGK. Plates 40 and 41, scale 1:4,500,000

6. Document Information

Glossary

Please see the Glossary of Permafrost and Related Ground Ice Terms for a general list of terms.

List of Acronyms

The following acronyms are used in this document:

CIA: Central Intelligence Agency
ESRI: Environmental Systems Research Institute
GIS: Geographic Information System

Document Creation Date

September 2005

Document Review Date

September 2005

Document URL

http://nsidc.org/data/docs/fgdc/ggd648_map_mongolia/index.html