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Data Set Documentation

Summary

The World Glacier Inventory (WGI) contains information for over 100,000 glaciers throughout the world. Parameters within the inventory include geographic location, area, length, orientation, elevation, and classification of morphological type, and moraines. The inventory entries are based on a single observation in time and can be viewed as a "snapshot" of the glacier at this time. The core of this collection is data from the World Glacier Monitoring Service, Zurich, Switzerland.

You can search the entire glacier inventory in one of several ways. The string search or latitude/longitude search allows you to narrow the search if you also enter parameters in the glacier Altitude/Size/Length field or in the Optional Advanced Search Features section. You can search the entire database by entering the inventory parameters without specifying any other search criteria. You can also choose to do a completely separate search by geographic regions or to extract the entire database from the ftp site (ftp://sidads.colorado.edu/pub/DATASETS/NOAA/G01130/).

NSIDC strongly encourages you to register as a user of this data product. As a registered user, you will be notified of updates and corrections. Please contact NSIDC User Services to register.

Citing These Data:

National Snow and Ice Data Center. 1999, updated 2007. World glacier inventory. World Glacier Monitoring Service and National Snow and Ice Data Center/World Data Center for Glaciology. Boulder, CO. Digital media.

To broaden awareness of our services, NSIDC requests that you acknowledge the use of data sets distributed by NSIDC. Please refer to the citation below for the suggested form, or contact NSIDC User Services for further information. We also request that you send us one reprint of any publication that cites the use of data received from our Center. This helps us to determine the level of use of the data we distribute. Thank you.

Table of Contents

1. Contacts
2. Overview
3. Detailed Data Description
4. Data Access and Related Collections
5. Quality Assessment and History of Updates
6. References and Related Publications
7. Acknowledgments
8. Document Information

1. Contacts

Investigators

Martin Hoelzle and Wilfried Haeberli
World Glacier Monitoring Service
Zurich, Switzerland
http://www.geo.unizh.ch/wgms/

See Data Sources for other data contributors.

Technical Contact

2. Overview

The history of systematic glacier monitoring on a large scale began in 1894, with the establishment of the International Glacier Commission at the 6th International Geological Congress in Zurich, Switzerland. Over time, observational procedures were standardized and the number of glaciers for which measurements were available grew. In 1986, the World Glacier Monitoring Service (WGMS) was established, under the auspices of the United Nations Environment Programme and other international organizations. WGMS collects measurements of glaciers from organizations around the world, and has compiled these regional inventories into a baseline World Glacier Inventory that will be updated every few decades (the response time for glacier mass balance). The World Glacier Inventory of glacier parameters serves as a snapshot of glacier conditions in the second half of the 20th century (Haeberli, 1998; Haeberli and Wallen, 1992).

Scientists are interested in the mass balance of glaciers, that is, whether a particular glacier is losing mass through increased melting or gaining mass through increased snowfall. Overall, the net mass balance for a sampling of glaciers from around the world is negative (WMO, 1998), with alpine glaciers showing a particularly marked decrease in mass over the last twenty-five years. Actual mass balance measurements are difficult and costly to obtain, so most glaciers must be studied through glacier parameters such as length, width, elevation, ablation area, and accumulation area (e.g., Haeberli and Hoelzle, 1995).

In 1998, WGMS and NSIDC agreed to work together to make the World Glacier Inventory widely available online. At that time, the WGMS World Glacier Inventory consisted of data from about 25,000 glaciers from North America, South America, Europe, and New Zealand. NSIDC maintained its own Eurasian Glacier Inventory of glacier parameters from over 34,000 glaciers in the former Soviet Union and China (Bedford and Haggerty, 1996). These data were acquired from a NOAA Environmental Services Data and Information Management project from V. Kotlyakov and M. Kunakhovitch (Institute of Geography, Russian Academy of Sciences, Moscow), and X. Chen (WDC for Glaciology, Lanzhou). Between 1995 and 1998, NSIDC and WGMS exchanged files of glacier parameters, with NSIDC providing WGMS with glacier data from China and the former Soviet Union, and WGMS providing NSIDC with the WGMS World Glacier Inventory data.

The new World Glacier Inventory contained more than 67,000 glaciers was made available online at NSIDC in 1999. Subsequently, a number of users made NSIDC aware of errors in the World Glacier Inventory for some data from the former Soviet Union and China. Please see the Quality Assessment and History of Updates section of this documentation for more information.

Measuring glaciers is a labor intensive process that employs traditional field surveys in hard-to-access and sometimes hazardous places. For this reason only a small percentage of the world's glaciers have been measured at all. Air photos and high resolution satellite imagery can sometimes supplement field work. The Global Land Ice Monitoring from Space (GLIMS) project is designed to monitor glaciers using data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument. Data from GLIMS may eventually supplement the World Glacier Inventory.

To view GIS maps of glaciers, see the WGI Map Viewer, made available by the NOAA National Geophysical Data Center.

3. Detailed Data Description

Data Sources

Data from the former Soviet Union were provided by V. Kotlyakov and M. Kunakhovitch, Institute of Geography, Russian Academy of Sciences, Moscow. Chernova provided additional data from the former Soviet Union at a later date (see the Quality Assessment and History of Updates). Chinese glacier data were provided by X. Chen, WDC for Glaciology, Lanzhou, China and by T. Che, Cold and Arid Regions Environmental and Engineering Research Institute (CAREERI), Chinese Academy of Sciences, China. Data for selected Alaskan glaciers were provided by V. Valentine and K. Echelmeyer, Geophysical Institute, University of Alaska, Fairbanks. All other data were compiled by and received from M. Hoelzle, World Glacier Monitoring Service (WGMS), Zurich, Switzerland.

Data Format

The data are stored in ASCII format, one record per line. Fields are separated by commas, and are arranged as follows. A description of each field is given below the list of field names.

Field Names

• glacier number
• glacier name
• latitude
• longitude
• coordinates
• number of basins
• topographic year
• topographic scale
• photo year
• total area
• area accuracy
• area in state
• area exposed
• mean width
• mean length
• maximum length
• maximum length exposed
• maximum length ablation
• orientation of the accumulation area
• orientation of the ablation area
• maximum altitude
• mean altitude
• minimum altitude
• minimum altitude exposed
• mean altitude accumulation
• mean altitude ablation
• classification type (next six fields)
  • primary classification
  • form
  • frontal characteristic
  • longitudinal profile
  • major source of nourishment
  • tongue activity
• moraine code (next two fields)
  • moraine type 1
  • moraine type 2
• period of observed activity, from
• period of observed activity, to
• snow line elevation
• snow line accuracy
• snow line date
• mean depth
• depth accuracy

Data Field Descriptions

The World Glacier Inventory contains the following data fields. Not all glaciers have entries in every field.

Glacier number:

The glacier ID number as defined by the World Glacier Monitoring Service's convention. The glacier ID number is a 12 character code formed by combining the following elements:

• 2 character country code or political unit (standard country codes used by the ISO - International Standards Organization)
• 1 character continent code
• 4 character drainage code
• 2 character free position code
• 3 character local glacier code

For instance, for the glacier ID, CH4L00185006, the CH is the country code (Switzerland), the 4 is the continent code (Europe), the L001 is the drainage basin code, the 85 is free position code, and the 006 is a local glacier code.

The six continent codes used in the database are as follows:

• 1 - South America
• 2 - North America
• 3 - Africa
• 4 - Europe
• 5 - Asia
• 6 - New Zealand

The nineteen country codes used in the database are as follows:

•   A - Austria
• BH - Bhutan
• RB - Bolivia
• CD - Canada
• RC - Chile
• CN - China
• EC - Ecuador
•   F - France
•   I - Italy
• NP - Nepal
• NZ - New Zealand
•   N - Norway
• PK - Pakistan
• PE - Peru
• SU - Soviet Union
•   E - Spain
•   S - Sweden
• CH - Switzerland
• US - United States

Note that glacier ID numbers assigned by former Soviet Union catalogues (Catalog of USSR Glaciers) diverge from the WGMS protocol. The numbering scheme for the FSU glaciers is as follows:

2 character country code
1 character continent code
1 character basin code
2 character volume code
1 character issue code
2 character part code
3 character local glacier code

For instance, for the glacier ID SU5T09101001, the SU is the country code (Soviet Union), the 5 is the continent code (Asia), the T is the drainage basin code, the 09101 refers to volume 9, issue 1, part 1 of the Catalog of USSR Glaciers, and the 001 is a local glacier code.

Glacier name:

The name of the glacier. Note that not every glacier has a name within the database. Often the name is the glacier's numerical position within its particular drainage subregion.

 

Latitude:

The latitude of the glacier, in decimal degrees North. Southern latitudes are negative.

Longitude:

The longitude of the glacier, in decimal degrees East. Western longitudes are negative.

Coordinates:

Local coordinates in UTM or other nationally determined format, for instance, the coordinates for U.S. glaciers are entered as words.

Number of basins:

Number of drainage basins.

Topographic year:

The year of the topographic map used for measurements of glacier parameters.

Topographic scale:

The scale of the topographic map used for measurements of glacier parameters.

Photo year:

The year of the photograph used for measurements of glacier parameters.

Total area:

The total area of the glacier, in square kilometers.

Area accuracy:

The accuracy of the area measurements on a percentile basis.

Area in state:

The total area in a particular political state.

Area exposed:

The area of open ice, in square kilometers.

Mean width:

The mean width of the glacier, in kilometers.

Mean length:

The mean glacier length, in kilometers.

Max length:

The maximum glacier length, in kilometers.

Max length exposed:

The maximum length of exposed ice, in kilometers.

Max length ablation:

The maximum length of ablation area, in kilometers.

Orientation of the accumulation:

The aspect of the accumulation area in degrees. The value -360 indicates an ice cap.

Orientation of the ablation:

The aspect of the ablation area in degrees. The value -360 indicates an ice cap.

Max altitude:

The highest glacier altitude, in meters a.s.l.

Mean altitude:

The mean glacier altitude, in meters a.s.l.

Min altitude:

The lowest glacier altitude, in meters a.s.l.

Min altitude exposed:

The lowest altitude of exposed ice, in meters a.s.l.

Mean altitude accumulation:

The mean altitude of the accumulation area, in meters a.s.l.

Mean altitude ablation:

The mean altitude of the ablation area, in meters a.s.l.

Primary classification

0 Uncertain or miscellaneous

1 Continental ice sheet

2 Ice field

3 Ice cap

4 Outlet glacier

5 Valley glacier

6 Mountain glacier

7 Glacieret and snowfield

8 Ice shelf

9 Rock glacier

Form

0 Uncertain or miscellaneous

1 Compound basins

2 Compound basin

3 Simple basin

4 Cirque

5 Niche

6 Crater

7 Ice apron

8 Group

9 Remnant

Frontal characteristic

0 Normal or Miscellaneous

1 Piedmont: Ice field formed on a lowland by lateral expansion of one, or coalescence of several, glaciers.

2 Expanded foot: Lobe or fan formed where the lower portion of the glacier leaves the confining wall of a valley and extends onto a less restricted and more level surface.

3 Lobed: Part of an ice sheet or ice cap, disqualified as an outlet or valley glacier.

4 Calving: Terminus of a glacier sufficiently extending into sea or lake water to produce icebergs.

5 Confluent: Coalescing, non-contributing.

6 Irregular, mainly clean ice (mountain or valley glaciers).

7 Irregular, debris-covered ice (mountain or valley glaciers).

8 Single lobe, mainly clean ice (mountain or valley glaciers).

9 Single lobe, debris-covered ice (mountain or valley glaciers).

Longitudinal profile

0 Uncertain or miscellaneous

1 Even, regular

2 Hanging

3 Cascading

4 Ice fall

5 Interrupted

Major source of nourishment

0 unknown

1 Snow

2 Avalanches

3 Superimposed ice

Activity of tongue

0 uncertain

1 Marked retreat

2 Slight retreat

3 Stationary

4 Slight advance

5 Marked advance

6 Possible surge

7 Known surge

8 Oscillating

Moraine code:

First digit refers to moraines in contact with present-day glacier

Second digit refers to moraines farther downstream

Both of the digits described above use the following coding system:

0 no moraines

1 terminal moraines

2 lateral and/or medial moraine

3 push moraine

4 combination of 1 and 2

5 combination of 1 and 3

6 combination of 2 and 3

7 combination of 1, 2, and 3

8 debris, uncertain if morainic

9 moraines, type uncertain or not listed

Period of observed activity:

Period of activity for which the tongue activity was assessed

Snow line elevation:

The observed or calculated location of the snow line. In meters above sea level

Snow line accuracy:

The snow line accuracy rating

Snow line date:

The date of observation of the snow line or the method of calculation of the snow line. The date of observation can range from a precise day (e.g. 1/1/54) to an individual year (e.g. 1967).

The glacier data from the former Soviet Union often uses an estimation technique to locate the snow line. The type of technique used is noted within the snow line date column.

They are as follows:

HESS: Snow line estimated from an analysis of a topographic map. Snow line is designated as the elevation where concave contour lines are replaced by convex contour lines in the accumulation area

KUROWS: The Kurowski method estimates snow line as the elevation which puts equal glacier areas above and below this line

HEFER: The snowline is estimated as the mean of the glacier terminus elevation and the peaks surrounding the accumulation area

SHEGLOV: The snowline is estimated as the elevation where the peak occurs on the curve of distribution of area by elevation

Mean depth:

The physical depth of the glacier, in meters

Depth accuracy:

The accuracy of the depth measurement on a percentile basis

Morphologic type:

This field was added in August, 2007, to correspond to morphologic types for Former Soviet Union data provided by Chernova.

4. Data Access and Related Collections

Downloading the Entire Database

You may pull the entire database from the ftp site (ftp://sidads.colorado.edu/pub/DATASETS/NOAA/G01130/).

Using the Search Interface

To search the entire glacier inventory, enter a word or words in the String Search box, enter latitude/longitude in the Geographic search, or select one or more inventory parameters. You can also choose to do a completely separate search by geographic region.

The default output format includes Glacier Name/Location, Extent, Elevation/Orientation, Dates, Classification and Accuracy. You can choose to include everything from each parameter by selecting "ALL" or you can display only a selection of available fields. Selecting the "ALL" option for any parameter overrides any other selections for that parameter.

The results are displayed in your Web browser as comma-delimited ASCII text. A blank space between commas or "-9999" indicates a missing value.

Search Tips

• You must select at least one input parameter, or the form will not query the database.
• Results for queries are based on glacier numbers, not glacier names, since all the glaciers are numbered, but not all are named.
• Defaults for the numerical input fields are 0.
• The database uses the WGMS field names and definitions.
• Queries for glaciers in Caucasus will return only those glaciers in the Caucasus that drain to the Black Sea or to the Caspian Sea.
• In the query result, missing data may be by indicated by either "-99" or by a blank space between commas.
• When you choose a continent, the top of the output format form tells you what continent you selected, but when you choose a region, the top of the output form lists the subregions within that region.
• Queries on the glacier number or glacier name are not case sensitive. Wild-cards are not allowed in searches. Searches return anything that contains the string entered into the search box. For a specific example, see the next tip on String Searches.
• For the String Search, the search will return anything that contains the characters entered into the search box. For instance, if you type "ice" the search will return records containing "ice," but it will also return such terms as Monticello, Price, Erpice, Icefall, and Carnicero.
• To extract all the information about glaciers for a specific country, enter the country code and continent code in the glacier number search box. For instance, the string "CH4" will return all the records for Switzerland.
• For United States glaciers, the coordinates are words that may help users determine a glacier's location, for instance, Mt. Whitney, Devils Postpile, Lone Pine, Arctic.
• Note that the output form shows the database query that was generated from your input and may not exactly match the terms that you entered.
• If you are building your query using the "Extract Data for Select Regions" form, you can select more than one region. The largest geographic region selected in each area takes precedence over any subregions selected from the same area.
• For the following glaciers, the database uses 0,0 for the latitude and longitude measurements instead of the actual coordinates:

  Glacier Number  Glacier Name     Lat  Lon
  F4N01154C15     NEVE              0    0
  F4N01154C16     NEVE              0    0
  F4N01154C17     GROS JEAN         0    0
  F4N01154C18     AIGUILLES D'ARV   0    0
  F4N01154C19     GROUPE            0    0
  F4N01154D01     NEVE              0    0
  F4N01154D02     GLACIER ROCHEUX   0    0
  F4N01154D03     ST SORLIN EST     0    0
  F4N01154E01     ARGENTIERE EST    0    0
  F4N01154E02     ARGENTIERE OUES   0    0
  F4N01154E03     NEVE              0    0
  F4N01154E04     NEVE              0    0
  F4N01154E05     NEVE              0    0
  F4N01154E06     COMBEROUSSE       0    0
  F4N01154E07     CLARANT           0    0
  F4N01221A01     NEVES DU CHABLAI  0    0
  RB1D22182882                      0    0
  RB1D22182884                      0    0
  RB1D22182885                      0    0
  RB1D22182890                      0    0
  RB1D22182897                      0    0
  RB1D22182899                      0    0
  RB1D22182911                      0    0
  RB1D22182918                      0    0
  RB1D22183224                      0    0
  US2M10091001    PARADISE          0    0
  US2M10091003    INGRAHAM          0    0
  US2M10091004    WHITMAN           0    0
  

• In Longitude/Latitude Searches, "0" is not a valid input.

Related NSIDC Data Collections

• Dyurgerov, Mark. 2002, updated 2005. Glacier Mass Balance and Regime: Data of Measurements and Analysis. INSTAAR Occasional Paper No. 55, ed. M. Meier and R. Armstrong. Boulder, CO: Institute of Arctic and Alpine Research, University of Colorado. Distributed by National Snow and Ice Data Center, Boulder, CO
• Echelmeyer, K.A., V.B. Valentine, and S.L. Zirnheld. 2002, updated 2004. Airborne Surface Profiling of Alaskan Glaciers. Boulder, CO: National Snow and Ice Data Center. Digital Media.
• William O. Field, compiler. 1978. Glacier Photograph Collection.Boulder, CO: National Snow and Ice Data Center.
• Weidick, A., Boeggild, C. E., and Knudsen, N. T. 1992: Glacier Inventory of West Greenland, Digital data available from the National Snow and Ice Data Center (nsidc@nsidc.org). University of Colorado, Boulder, Colorado.
• Weidick, A., Boeggild, C. E., and Knudsen, N. T. 1992. Glacier Inventory of West Greenland. Boulder, CO: National Snow and Ice Data Center. Digital media.
• Global Land Ice Measurements from Space (GLIMS)
• To view GIS maps of WGI glaciers, see the WGI Map Viewer, made available by the NOAA National Geophysical Data Center.

Please search our data catalog for other NSIDC glacier data sets.

Other Related Data Collections

A number of glacier inventory and mass balance data sets are available from the World Glacier Monitoring Service based in Zurich, Switzerland. description

5. Quality Assessment and History of Updates

Data obtained from WGMS were subjected to plausibility checks at WGMS while they were being loaded into the database in Zurich. Errors uncovered during the plausibility check were printed out and sent to the data collectors for review. The final accuracy of the data is the responsibility of the data collectors in the individual countries (Hoelzle and Trindler, 1998).

Data received at NSIDC from X. Chen (China) and V. Kotlyakov (former Soviet Union) were checked at NSIDC for impossible values that might indicate digitizing errors. Therefore, data values may exist that are irregular but not impossible. For example glacier CN5Y812B0008 has a frontal characteristic value that indicates calving. Though the glacier's high altitude might indicate an error in the classification, calving into a small lake is not impossible so the data remain unchanged.

Checks on the data were both general and field-specific. General checks were applied to all fields and included ensuring that data were recorded in a consistent manner. Field-specific checks included ensuring that maximum, minimum, and lengths were accurate in relation to each other (that is, maximum exceeds mean which exceeds minimum), maximum and minimum elevations of glaciers and snowlines were appropriate for their location, and total and ablation areas were accurate in relation to each other (ablation area cannot exceed total area). NSIDC asked the data contributor about "impossible" data values. Data that were corrected on recommendation from data contributors are indicated in the glacier quality field. After these checks took place, data from glaciers in China and the former Soviet Union were sent to WGMS for incorporation in later versions of the WGMS database.

In 2001, former Soviet Union data were found to contain corrupted geodetic coordinate data as a result of a mistake in processing that took place at NSIDC. We corrected these data as of 4 May 2001. If you retrieved data from this region prior to this date and are using the latitude/longitude data, you should download the data again.

In detail, data were corrupted when the latitude/longitude coordinates for the glaciers between +33.00 and +181.17 degrees longitude and between +33.00 and +81.85 degrees latitude were converted twice from degrees-minutes format to decimal degree format in the process of putting the data in the database. The version of the text (ASCII) file of the whole database, available at (ftp://sidads.colorado.edu/pub/DATASETS/NOAA/G01130/), contained uncorrupted data in decimal degree format for these particular glaciers, while the coordinates for the rest of the glaciers were in degrees-minutes format. Both the ASCII file of the entire database, and the data in the Web-accessible database, have now been fixed. They contain only decimal degree formatted latitude/longitude data.

In March, 2003, NSIDC discovered discrepancies between glacier locations in the online WGI database and glaciers in the WGMS database. The locations for the glaciers in the WGI at NSIDC had errors with a magnitude of 0.005 degrees or approximately 500 m. We hypothesize that the differences were due to a rounding error that occurred during a database migration in September 2001. The glacier locations have been corrected and the data have been reloaded as of March 15, 2003.

In January 2004, a user notified NSIDC about probable errors in the WGI orientation fields. It was found that the Soviet Union Glacier Inventory and data from China had errors in the Orientation Ablation and Orientation Accumulation fields of the database. Specifically, for glaciers with a country code of CN (for China) and SU (for Russia) had east and west reversed. We corrected these fields by swapping E and W, NE and NW, and SE and SW. The glacier Orientation Ablation and Orientation Accumulation fields have been corrected and the data have been reloaded as of 5 May 2005. We thank Dr. Ian S. Evans for bringing this to our attention.

In February 2007, a user informed NSIDC that a glacier with an area of 5360 squared kilometers does not exist in the Pamirs. The "total area" field for glacier number SU5X14319097 was changed from 5360 to -9999 (the default value).

In August 2007, the database was updated with data from Lyudmila Chernova. Between 2002 and 2004, NSIDC corresponded with L. Chernova concerning errors in glacier IDs that she had identified in glaciers from Volume 13 of the approximately 80 volume set Catalog of USSR Glaciers. These glaciers had the drainage basin incorrect, with "A" where "X" should have been. She provided corrected glacier IDs, which were fixed in the database in August 2007. A complete list of the 368 corrected glacier IDs is available as a text file. A map provided by Chernova provides data users with a view of the different regions. The map visually shows how regions "5A" and "5X" differ geographically.

Chernova also noted that glaciers from Vol. 15 Issue 1 Chapters 5, 6, 7 and 8, and Vol. 15 Issue 2 Chapter 1 were missing from the WGI as well as glaciers from Vol. 14 Issue 3 Chapter 9; Vol. 13 Issue 2 Chapter 5; and Vol. 16 Issue 2 Chapter 2. Chernova provided NSIDC with the missing data, which were added to the database in August 2007.

The data files from Chernova included a six-digit "Classification Code" field (e.g. 650100). These codes relate to four one-digit WGI fields and to one newly added two-digit "Morphologic Type" field. This field was added to the database (August 2007) and only contains values for data provided by Chernova. Using the six-digit example above, the first two-digit value corresponds to the "Morphologic Type" (65) and the following four fields correspond to Frontal Characteristic (0), Longitudinal Profile (1), Major Source of Nourishment (0) and Tongue Activity (0). Below is table showing the relationship between Morphological Types and their description.

Some of the records supplied by Chernova have a glacier name with one, two or three digits that correspond to the last digits of the glacier ID.

Chernova followed the descriptions in this document for the "orientation of the accumulation" and "orientation of the ablation" fields. These values are provided in degree rather than direction (e.g. 360 versus N). Other data contributors provide values for these two fields using direction rather than degree. To convert between degrees and direction (per Chernova's description): 360 = N, 90 = E, 180 = S, 270 = W, 45 = NE, and so forth.

Records from Chernova listed area accuracy as a range (e.g. 10%-20%). Since the area accuracy field is generally a single number in the WGI database, we converted this to a single value by taking the median (e.g 12.5, based on the 10%-15% range). A precision in estimating area accuracy is not implied by the precision of this statistic. We thank Ian Evans for reformatting the data files provided by Chernova.

In November 2007, 46,394 glaciers from the Chinese glacier inventory were supplied to NSIDC by Dr. Tao Che. Many contributed to the data collection, including Dr. Xin Li and Mr. Lizong Wu, among others. The data were retrieved from the book titled "Chinese Glacier Information System" (in Chinese). T. Che provided a file listing the regions covered by this update. These regions include: Ertix He (Kara Irtysh), Yellow River, Yangtze River, Lancang Jiang, Nu Jiang, Ganga River, Indus River, Central Asian Drainage Basin, Eastern Asian Drainage Basin, and the Tibet Drainage Basin. To see the direct mapping between codes in the Glacier ID and the regions they represent, click here to view the five files (first.txt to fifth.txt).

Of the 46,394 glaciers that T. Che provided to NSIDC, 34,254 glaciers were added to the World Glacier Inventory and the other 12,140 glaciers replaced existing glaciers in the database. Many corrections were applied to the data. Here is a list of Glacier IDs that were replaced. There are now 43 glaciers in the WGI remaining from the original Chinese glacier inventory (data provider, Chen). To access the data from this update, go to the WGI Search interface and select "CAREERI, Lanzhou, China. Che" from the Data Contributor Search pull-down menu.

NSIDC performed a basic quality check on the new Chinese glacier inventory. B. Raup identified and corrected five coordinates that were incorrect, wrote a script to convert the coordinates from degrees and minutes to decimal degrees, and identified inconsistencies with certain coordinates based on a visual assessment on a map. For example, the Glacier ID CN5O282A0448 contains latitude (20.228) and longitude (95.83017) coordinates that are most likely too far south to be in the Chinese glacier inventory. The bulleted list below shows changes made at NSIDC to the original data given to us by T. Che:

• For a list of changes we made at NSIDC per recommendations by B. Raup, click here.
• For the "snow_line_date" column, we changed two digit values to four digit values, but we kept "0" values. For example, "80" was changed to "1980".
• L. Ballagh reformatted the data to facilitate input to the database and separated the six-digit "GLA_CLASS" field into these six corresponding fields: primary classification, form, frontal characteristic, longitudinal profile, major source of nourishment and tongue activity.
• The data contained a two-digit field for "moraines". L. Ballagh separated the two-digit field into a one-digit "moraines1" field and a one-digit "moraines2" field.
• Blank fields were converted to -9999 by I. Wang (NSIDC) in the database.

Users will notice that some columns contain multiple values. For example, there may be one, two or three years listed in the "topographic year" field. According to Mr. Wu, "There are only one reference data in a five level glacier catchment, and if a glacier catchment uses different (two or more) reference data, there will be multiple values." We interpret this to mean that there is a many to many relationship between glaciers and the reference data (maps).

Note that some fields given to us by T. Che were not added to the WGI database because they are not valid WGI fields. For example, "Ice Volume" is not a valid WGI field. In addition to the WGI update, glacier outlines were also provided and these outlines are now available through the Global Land Ice Measurements from Space (GLIMS) Glacier Database interface.

In March of 2008, the World Glacier Inventory Extract Select Regions interface and maps were updated.

6. References and Related Publications

• Bedford, D. and C. Haggerty. 1996. New digitized glacier inventory for the former Soviet Union and China. Earth System Monitor, ISSN 1068-2678, NOAA Environmental Information Services Office, 6(3), 8-10.
• Evans, I.S. 2005. Global variations of local asymmetry in glacier altitude: separation of north-south and east-west components, J. Glaciology 51(174), 469-482.
• Evans, I.S. 2006. Glacier distribution in the Alps: statistical modelling of altitude and aspect. Geogr. Ann., 88 A (2),115-133.
• Evans, I.S. 2006. Local aspect asymmetry of mountain glaciation: A global survey of consistency of favoured directions for glacier numbers and altitudes, Geomorphology 73, 166-184.
• Haeberli, W. 1998. Historical evolution and operation aspects of worldwide glacier monitoring. in Into the second century of worldwide glacier monitoring: prospects and strategies. Studies and reports in hydrology, No. 56. edited by W. Haeberli, M. Hoelzle, and S. Suter. UNESCO Publishing, Paris. pp 36-52.
• Haeberli, W. and M. Hoelzle. 1995. Application of inventory data for estimating characteristics for and regional climate change effects on mountain glaciers: a pilot study with the European Alps. Annals of Glaciology, 21, 206-212.
• Haeberli and Wallen. 1992. Glaciers and the Environment UNEP GEMS Environment Library No. 9, 24 pp.
• Hoelzle, M., M. Trindler. 1998. Data Management and Application. in Into the second century of worldwide glacier monitoring: prospects and strategies. Studies and reports in hydrology, No. 56. edited by W. Haeberli, M. Hoelzle, and S. Suter. UNESCO Publishing, Paris. pp 53-72.
• World Glacier Monitoring Service, compiler. 1989. World Glacier Inventory Status 1988. Wallingford, Oxfordshire, UK: International Association of Hydrological Sciences; Nairobi, Kenya: Global Environment Monitoring System of the United Nations Environment Programme; Paris, France: United Nations Educational, Scientific, and Cultural Organization.
• WMO. 1998. The Global Climate System Review, December 1993-May 1996 J.M. Nicholls, ed., World Climate Data and Monitoring Programme, WMO-No. 856, 95 pp.

7. Acknowledgments

This data set was originally made available as the result of an informal collaboration between Martin Hoelzle of the World Glacier Monitoring Service (WGMS) in Zurich, Switzerland, and Christopher Haggerty, formerly of the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado, under the guidance of Wilfried Haeberli, WGMS director, and Roger Barry, NSIDC director. The NOAA Environmental Services Data and Information Management (ESDIM) program funded acquisition of glacier data from China and the former Soviet Union, and funded the development of the interface to the data.

Data were first made available online from NSIDC in 1999. In August, 2001, a number of errors were corrected (see Quality Assessment and History of Updates), online subsectioning capabilities were improved, data were migrated to a Sybase database, and the documentation was revised. Bruce Raup, Alejandro Machado, I-Pin Wang, Robin Welsh, and Michon Scott, all of NSIDC, performed this work.

We are grateful to Dr. Ian S. Evans, Department of Geography at Durham University, for bringing errors in the WGI to our attention. His generous contribution of time and expertise has resulted in an improved data product.

The NOAA team (F. Fetterer, L. Ballagh, and J. Kovarik) maintains this product at NSIDC. This work was supported by funding from NOAA’s National Environmental Satellite, Data, and Information Service and the National Geophysical Data Center.

8. Document Information

Document Authors

This document was originally prepared by C. Haggerty and published in 1999. It has been updated by F. Fetterer and L. Ballagh and by NSIDC's team of writers including R. Welsh and K. Webster.

Revision Date

May 2005 - F. Fetterer revised the format and added to the section on Quality Assessment and History of Updates

Feb 2007 - L. Ballagh made an addition to the section on Quality Assessment and History of Updates

Aug 2007 - F. Fetterer and L. Ballagh made an addition to the section on Quality Assessment and History of Updates

Nov 2007 - L. Ballagh updated the Quality Assessment section.

Nov 2007 - L. Ballagh added updates for the Chinese glacier inventory. Updates were made to the Quality Assessment and History of Updates, the Summary, Citing These Data and Data Sources sections of this document.

Mar 2008 - L. Ballagh added a comment in the Quality Assessment section about the updates to the Select Extract Regions section of the World Glacier Inventory interface.

Document URL

http://nsidc.org/data/docs/noaa/g01130_glacier_inventory/