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Active Layer Monitoring, Arctic and Subarctic Canada

Summary

This project involves measuring regional and site variability in maximum annual active layer development and vertical surface movement over permafrost, and monitoring sites over time in order to observe trends. The project records maximum thaw penetration, maximum heave and subsidence, late season snow depths, current depth of thaw, elevation, and soil properties. Some sites are twinned with soil- and air-temperature recording equipment.

The project includes about 60 monitoring stations extending from Fort Simpson, Canada, in the upper Mackenzie River valley to the Beaufort Sea coast at North Head, Richards Island, Canada. Ten of the sites are part of the International Permafrost Association's (IPA's) Circumpolar Active Layer Monitoring (CALM) Program. CALM site numbers are in parentheses after the site names: North Head (C3), Taglu (C4), Lousy Point (C5), Reindeer Depot (C7), Rengleng River (C8), Mountain River (C9), Norman Wells (C11), Ochre River (C13), Willowlake River (C14), and Fort Simpson (C15). See the CALM entry for geographic coordinates and site history for all CALM sites.

These data are the property of the people of Canada and the responsibility of the Geological Survey of Canada. If published, adequate acknowledgment is expected. Please contact F.M. Nixon regarding use of the data set or access to the extended data.

Citing These Data:

We kindly request that you cite the use of this data set in a publication using the following citation example. For more information, see our Use and Copyright Web page.

Nixon, Mark F. 1998, updated 2009. Active layer monitoring, arctic and subarctic Canada. Boulder, Colorado USA: National Snow and Ice Data Center. Digital media.

Overview Table

Category Description
Data format Rich Text Format (RTF)
Spatial coverage and resolution Arctic and Subarctic Canada, including 10 Canadian CALM sites. Geographic extent is as follows:

Northernmost latitude: 69° 43' N
Westernmost longitude: 135° 20' W
Southernmost latitude: 61° 53' N
Easternmost longitude: 121° 36' W

Depth < 2 meters. Sites about 15 minutes apart in delta, every 0.5 degree of latitude in valley, clusters of sites a few hundred meters apart.
Temporal coverage and resolution 1991 to 2007
File size 865 KB
Procedures for obtaining data Available via FTP

Table of Contents

1. Contacts and Acknowledgments
2. Detailed Data Description
3. References and Related Publications
4. Document Information

1. Contacts and Acknowledgments:

Investigator(s) Name and Title:

Mark F. Nixon
Geological Survey of Canada
191-601 Booth Street
Ottawa, ON, Canada, K1A 0E8

Technical Contact:

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

2. Detailed Data Description:

Format:

Data are in Rich Text Format (RTF). Data are presented by study site, with the following information for each site:

Site: site name and CALM number (if appropriate)
Responsibility: person responsible for data at this site
Location: latitude and longitude
Elevation: in meters
Slope: e.g., flat
Landform: e.g., glaciolacustrine plain, alluvial plain
Soil:: description of soil (e.g., well drained silty sand)
Vegetation: description of vegetation
Installations: description of instruments and methods

The maximum annual active layer is reported for each year in integer centimeters, with a precision of ±1 cm. Data are reported as maximum values when the value of maximum subsidence was not available. The ground surface height measured during mid-summer in the year following the record was used as a minimum subsidence at the time of maximum thaw. Minimum values usually result from thaw progressing below the measuring range of the instrument. Missing values at the beginning of records result from a variable start of record for different sites.

Description of Data Files:

The data set consists of one RTF file (ggd353data_v5.rtf) that contains all the data.

Version History

The latest release of these data is Version 6, current as of 1 January 2009. Previously released copies of files with names that do not include "_v6" are obsolete and should be replaced with the Version 6 copy. Changes since Version 5 are highlighted in red in the Version 6 RTF document. Version 6 contains additional data from 2006 and 2007, more Mean Annual Air Temperatures and Mean Annual Ground Temperatuures for the sites and updated station data plus a few minor edits.

Version 5 contained one year of additional data and data corrections since Version 4. Version 5 was only available as a single RTF file.

Version 4 contained two years of additional data and data corrections since Version 3. Version 4 was only available as a single RTF file, while Version 3 also included ASCII versions of the data.

Version 3 data contained two years of additional data and data corrections since Version 2, released on the Circumpolar Active-Layer Permafrost System Version 2.0. Version 1 only included data from the CALM sites and used a different file naming convention.

Spatial Coverage:

The active-layer monitoring system extends from Fort Simpson, Canada, in the upper Mackenzie River valley to the Beaufort Sea coast at North Head, Richards Island, Canada. The study area includes 10 Canadian CALM sites. Geographic extent is as follows:

Northernmost latitude: 69° 43' N
Westernmost longitude: 135° 20' W
Southernmost latitude: 61° 53' N
Easternmost longitude: 121° 36' W

A site location table lists individual site locations and corresponding CALM numbers.

Temporal Coverage:

Data begin in 1991 and continue to 2008. Data collection is ongoing and is added as it becomes available.

Data Acquisition Methods:

Maximum annual thaw penetration and maximum heave and subsidence of the ground surface are measured using a modified version of a frost tube developed by Mackay (1973) and Nixon et al. (1995). The device is a removable water-filled, clear plastic observation tube, 2 cm in diameter, approximately 2.5 m long inside a 2.5-cm diameter, heave-resistant access tube (Tarnocai et al 2004), which is long enough (approximately 4 m) to be anchored in permafrost upon installation. See Figure 3 in Nixon and Taylor (1994).

The ice-water interface in the observation tube corresponds to the frost table in the surrounding ground. A 3-mm diameter colored marker, which is dropped into the tube each year prior to time of maximum thaw, rests on the ice surface. It descends during the thaw season to be trapped at the maximum depth on freeze in late summer or fall. Maximum heave and subsidence are recorded between observations by a scriber attached to a weighted sleeve around the outside of the access tube that scratches a painted surface on either side of a reference mark (renewed at each visit). Tubes were installed using a lightweight pump that is approximately 10 kg with a maximum discharge of 100 liters/min. The active layer is defined as the thaw recorded in the thaw tube minus the height of the tube above ground at maximum surface subsidence, which is assumed to occur about the time of maximum thaw.

Many of the thaw tube sites are also instrumented with automatic air and ground temperature loggers (Tarnocai et al, 2004). At 40 sites, a 6-plate, 12-cm diameter radiation shield (R.M. Young, model 41301-5) was mounted 1.5 m above the ground surface. Air temperatures are measured by a thermistor in the shield that is connected to a single-channel, miniature data logger in the lower part of the mast (see Figure 5 in Nixon et al. (1995). A similar miniature data logger with an internal sensor is buried near the base of the air temperature mast at a nominal depth of 3 to 7 cm to measure near-surface ground temperatures. Two types of miniature data loggers are used: HOBO loggers (Onset Computer Corp, USA.), range -37 to 46° C, resolution 0.25° C; and Minilog loggers (Vemco Ltd., Canada), -50 to 40° C, resolution 0.3° C. Temperatures are recorded every two to six hours for a year or more before servicing.

The snow pack observations was observed during March or April and reported as a range of values from all the observations at the site.

3. References and Related Publications:

Aylsworth, J.M., and P.A. Egginton. 1994. Sensitivity of slopes to climate change. Mackenzie Basin Impact Study, Interim report #2, Proceedings of the sixth biennial AES/DIAND meeting on northern climate & mid study workshop of the Mackenzie basin impact study. Environment Canada.

Dyke, L.D., 2000. Stability of permafrost slopes in the Mackenzie Valley; In The Physical Environment of the Mackenzie Valley, Northwest Territories: A Base Line for the Assessment of Environmental Change, Dyke LD, Brooks GR (eds). Bulletin 547, Geological Survey of Canada, p. 161–169.

Edlund, S.A., B.T. Alt, and K.L. Young. 1989. Interaction of climate, vegetation, and soil hydrology at Hot Weather Creek, Fosheim Peninsula, Ellesmere Island, Northwest Territories. In Current Research 1989-D. Ottawa: Geological Survey of Canada.

Hinzman, L.D., and D.L. Kane. 1992. Potential response of an arctic watershed during a period of global warming. Journal of Geophysical Research 97(D3): 2811-2820.

Kokelj S.V. and C.R. Burn, 2005. Geochemistry of the active layer and near-surface permafrost, Mackenzie delta region, Northwest Territories, Canada; Canadian Journal of Earth Sciences, 42(1), p. 37-48.

Mackay, J.R. 1976. Ice-wedges as indicators of recent climatic change, western Arctic coast. In Current Research 1976-A. Ottawa: Geological Survey of Canada.

Mackay, J.R. 1975. The stability of permafrost and recent climatic change in the Mackenzie Valley, N.W.T. In Report of Activities, Part B, Geological Survey of Canada, Paper 75-1B. Ottawa: Geological Survey of Canada.

Mackay, J.R. 1973. A frost tube for the determination of freezing in the active layer above permafrost. Canadian Geotechnical Journal 10: 392-396.

Nixon, F.M. 2000. Thaw-depth monitoring. In Physical Environment of the Mackenzie Valley, Northwest Territories: a Base Line for the Assessment of Environmental Change, L.D. Dyke and G.R. Brooks, eds. Geological Survey of Canada Bulletin 547: 119-126.

Nixon, F.M., and A.E. Taylor. 1998. Regional active layer monitoring across the sporadic, discontinuous and continuous permafrost zones, Mackenzie Valley, northwestern Canada. Proceedings of the 7th International Conference on Permafrost, Yellowknife.

Nixon, F.M., A.E. Taylor, V.S. Allen, and F. Wright. 1995. Active layer monitoring in natural environments, lower Mackenzie Valley, Northwest Territories. In Current Research 1995-B. Ottawa: Geological Survey of Canada.

Nixon, F.M., and A.E. Taylor. 1994. Active layer monitoring in natural environments, Mackenzie Valley, Northwest Territories. In Current Research 1994-B. Ottawa: Geological Survey of Canada.

Nixon, F.M., C. Tarnocai, and L. Kutny. 2003. Long-term active layer monitoring: Mackenzie Valley, northwest Canada. In Permafrost, Vol. 2, M. Philips, S. Springman, and L.U. Arenson, eds. Lisse, The Netherlands: A.A. Balkema Publishers, Swets & Zeitlinger.

Smith, S.L., M.M. Burgess, and F.M. Nixon. 2001. Response of active-layer and permafrost temperatures to warming during 1998 in the Mackenzie Delta, Northwest Territories and at Canadian Forces Station Alert and Baker Lake, Nunavut. In Current Research 2001-E5. Ottawa: Geological Survey of Canada.

Tarnocai C., F.M. Nixon, and L. Kutny. 2004. Circumpolar Active-Layer Monitoring (CALM) sites in the Mackenzie Valley, northwestern Canada. Permafrost and Periglacial Processes 15(2): 141-153.

Quinton WL, Shirazi T, Carey SK, Pomeroy JW., 2005. Soil water storage and active-layer development in a sub-alpine tundra hillslope, southern Yukon Territory, Canada; Permafrost and Periglacial Processes, 16: p. 369–382.

Waelbroeck, C., P. Monfray, W.C. Oechel, S. Hastings, and G. Vourlitis. 1997. The impact of permafrost thawing on the carbon dynamics of tundra. Geophysical Research Letters 24: 229-232.

Wolfe, S.A., E. Kotler, and F.M. Nixon. 2000. Recent warming impacts in the Mackenzie Delta, Northwest Territories, and northern Yukon Territory coastal areas. In Current Research 2000-B1. Ottawa: Geological Survey of Canada. Document is available online at:
http://gsc.nrcan.gc.ca/bookstore/.

4. Document Information:

Document Creation Date:

January 2003

Document Revision Dates:

January 2009
September 2007
January 2007
April 2005

Document URL:

http://nsidc.org/data/docs/fgdc/ggd353_activelayer_canada/index.html