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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.
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.
National Snow and Ice Data Center. 1999, updated 2009. World glacier inventory. World Glacier Monitoring Service and National Snow and Ice Data Center/World Data Center for Glaciology. Boulder, CO. Digital media.
Martin Hoelzle and Wilfried Haeberli
World Glacier Monitoring Service
Zurich, Switzerland
http://www.geo.unizh.ch/wgms/
See Data Sources for other data contributors.
NSIDC User Services
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
Boulder, CO 80309-0449 USA
phone: +1 303.492.6199
fax: +1 303.492.2468
form: Contact NSIDC User Services
e-mail: nsidc@nsidc.org
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.
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. Glacier data for Chile were provided by the Centro de Estudios Avanzados en Zonas Aridas (CEAZA). All other data were compiled by and received from M. Hoelzle, World Glacier Monitoring Service (WGMS), Zurich, Switzerland.
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 in Table 1 in the Data Field Descriptions section of this document.
The World Glacier Inventory contains the following data fields. Note: Not all glaciers have entries in every field.
| Field Name | Description | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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:
The six continent codes used in the database are as follows:
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. |
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| 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. |
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| Longitude | The longitude of the glacier, in decimal degrees East. Western longitudes
are negative. |
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| Coordinates | Local coordinates in UTM or other nationally determined format, for instance,
the coordinates for U.S. glaciers are entered as words. |
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| Number of basins | Number of drainage basins | ||||||||||||
| Topographic year | The year of the topographic map used for measurements of glacier parameters. |
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| Topographic scale | The scale of the topographic map used for measurements of glacier parameters. |
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| Photo year | The year of the photograph used for measurements of glacier parameters. |
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| Total area | The total area of the glacier, in square kilometers. |
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| Area accuracy | The accuracy of the area measurements on a percentile basis.
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| Area in state | The total area in a particular political state. |
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| Area exposed | The area of open ice, in square kilometers. |
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| Mean width | The mean width of the glacier, in kilometers. |
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| Mean length | The mean glacier length, in kilometers. |
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| Max length: | The maximum glacier length, in kilometers. |
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| Max length exposed | The maximum length of exposed ice, in kilometers. |
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| Max length ablation | The maximum length of ablation area, in kilometers. |
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| Orientation of the accumulation | The aspect of the accumulation area in degrees. The value -360 indicates
an ice cap. |
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| Orientation of the ablation | The aspect of the ablation area in degrees. The value -360 indicates an
ice cap. |
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| Max altitude | The highest glacier altitude, in meters a.s.l. |
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| Mean altitude | The mean glacier altitude, in meters a.s.l. |
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| Min altitude | The lowest glacier altitude, in meters a.s.l. |
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| Min altitude exposed: | The lowest altitude of exposed ice, in meters a.s.l. |
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| Mean altitude accumulation | The mean altitude of the accumulation area, in meters a.s.l. |
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| Mean altitude ablation | The mean altitude of the ablation area, in meters a.s.l. |
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| Primary classification |
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| Form |
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| Frontal characteristic |
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| Longitudinal profile |
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| Major source of nourishment |
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| Activity of tongue |
|
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| Moraine code: |
First digit refers to moraines in contact with present-day glacier.
Second digit refers to moraines farther downstream Both of the digits 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 |
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| Period of observed activity | Period of activity for which the tongue activity was assessed | ||||||||||||
| snowline elevation | The observed or calculated location of the snowline. In meters above sea
level |
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| snowline accuracy | The snowline accuracy rating.
Note: snowline elevation concerns the altitude of the transient snowline at the end of the ablation season or, in most cases and for practical reasons, at the time of photography. |
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| snowline date |
The date of observation of the snowline or the method of calculation of
the snowline. 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 snowline. The type of technique used is noted within the snow line date column. They are as follows: HESS: snowline 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 snowline 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 |
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| Mean depth | The physical depth of the glacier, in meters. Note: Mean depth is given only if actually measured (for instance by drilling or radio-echo soundings). |
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| Depth accuracy | The accuracy of the depth measurement on a percentile basis.
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| Morphologic type | This field was added in August 2007 to correspond to morphologic types for Former Soviet Union data provided by Chernova |
You may pull the entire database from the ftp site (ftp://sidads.colorado.edu/pub/DATASETS/NOAA/G01130/).
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.
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
Please search our data catalog for other NSIDC glacier data sets.
A number of glacier inventory and mass balance data sets are available from the World Glacier Monitoring Service based in Zurich, Switzerland. description
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 July 2010, some errant lat/lon values were discovered. The values that formerly appeared as -10165.6500 and 10165.6500 were determined to be missing data values. They are now displayed in the ASCII search interface output as blank spaces between commas in the lat and lon columns. Approximately 24,000 values were affected.
In December 2009, NSIDC changed all of the -9999 values (which indicate a missing value) in the ASCII search interface output to a blank space between commas. Before making the change, the NOAA@NSIDC team discussed it with a scientist at NSIDC and also with a scientist at the World Glacier Monitoring Service to ensure that the change would have a minimal impact (if any at all) on users who have already downloaded the data. The original WGMS database did not contain -9999 values, so NSIDC has decided to make this change.
Also in December, incorrect values for the Topographic Scale were noticed in the database. Occasionally, these values were listed as "1:-99990". After some investigation, it was determined that these values indicate missing data, so they are also now displayed as a blank space between commas in the ASCII search interface output.
In June of 2009, 157 glaciers from the Huasco Catchment in Chile were added to the database. These were provided by CEAZA. The elevation ranges were obtained from Chilean topographical maps (1955 aerophotogrammetrical restitution). The glacier areas and lengths were taken from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data.
In March of 2008, the World Glacier Inventory Extract Select Regions interface and maps were updated.
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:
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 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.
| Morphologic Type | Morphological Description |
|---|---|
|
36
|
slope glacier
|
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37
|
flat summit glacier
|
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51
|
dendritic
|
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52
|
compound
|
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53
|
valley
|
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63
|
corrie valley
|
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64
|
corrie
|
|
65
|
hanging
|
|
75
|
niche
|
|
76
|
crater
|
|
77
|
ice apron
|
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 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 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 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 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.
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.
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, K. Webster, and A. Windnagel.
July 2010: A. Windnagel added a note to the update history section.
June 2010: A. Windnagel added the schemas for accuracy ratings for area accuracy, snowline accuracy, and depth accuracy to Table 1.
December 2009: A. Windnagel changed the missing data value from -9999 to NULL. Also, reformatted the Data Field Descriptions section (put text into a table) and reversed the order of the Update History section so the newest updates are listed first.
June 2009: L. Ballagh added the Chilean glacier updates from CEAZA. Updates were made to the Data Sources, Data Format, Quality Assessment and History of Updates, and Revision Date sections of this document.
March 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.
November 200:- 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.
November 2007: L. Ballagh updated the Quality Assessment section.
August 2007: F. Fetterer and L. Ballagh made an addition to the section on Quality Assessment and History of Updates
February 2007: L. Ballagh made an addition to the section on Quality Assessment and History of Updates
May 2005: F. Fetterer revised the format and added to the section on Quality Assessment and History of Updates
http://nsidc.org/data/docs/noaa/g01130_glacier_inventory/