This data set contains air and soil temperatures collected from eight sites in Alaska between 1986 and 2001. The data were obtained by remote, battery-powered, computer-controlled automatic temperature loggers. Temperatures recorded were usually in the air, at the ground surface, in the active layer, at the permafrost table, and in the permafrost.
The research project was funded by the Arctic System Sciences (ARCSS) Program, grant number OPP-9531220.
Osterkamp, T. 1999, updated 2001. Daily air and active layer temperatures from permafrost observatories in Alaska, 1986-2001.. Boulder, CO: National Center for Atmospheric Research, ARCSS Data Archive. Digital media.
|Data format||Tab-delimited text files|
|Spatial coverage||Data were collected in Alaska, USA, located between 62.0º N and 71.0º N, and 154.0º W and 146.0º W|
|Temporal coverage and resolution||Dates of collection were between 1986-01-01 and 2002-01-01; measurements were collected daily, every 4 hours|
|File size||File sizes range between 77 and 303 KB|
|Parameter(s)||Air, ground surface, upper permafrost, and active layer temperatures|
1. Contacts and Acknowledgments
2. Detailed Data Description
3. Data Acquisition and Processing
4. References and Related Publications
5. Document Information
Thomas E. Osterkamp
University of Alaska Fairbanks
Fairbanks, AK 99775-7320
Data are available as tab-delimited text files (.txt extension). For some files, a header occupies the first row, and indicates either the actual depth (in meters, except for the GI487-95.txt file which is in centimeters), or the layer represented by each measurement. In other files, mean or instantaneous temperatures (in degrees C) for each day are shown for the air, ground surface, active layer at three levels (Al1, Al2, Al3), permafrost table at three levels (Pt1, Pt2, Pt3) and permafrost at three levels (Pf1, Pf2, Pf3).
Note: the first one to three columns may not be labeled, but typically contain date information in either MM/DD/YY or DD-MMM-YY format, and as a running total of the number of days from the beginning of the year of record, or the beginning of the 20th century.
File names are *YY-YY.txt, where * is the site, and YY-YY represents the years contained in the file. For example, wd86-96.txt contains data for the West Dock site starting in the fall of 1986 and continuing through the summer of 1996.
File sizes range between 77 and 303 KB.
Data were collected in Alaska, United States of America, at the following coordinates:
Southernmost latitude: 62º N
Northernmost latitude: 71º N
Westernmost longitude: 154º W
Easternmost longitude: 146º W
The depth at which data were collected ranged from 0 to approximately 1 m.
Data were collected between 1986-01-01 and 2002-01-01.
A logging interval of four hours was used with the logger recording the daily maximum, mean, and minimum air temperatures and the instantaneous and daily mean active layer and permafrost temperatures.
The parameters measured in this data set are air, ground surface, upper permafrost, and active layer temperatures.
The unit of measurement is degrees Celsius.
University Farm, 1996-2001
The loggers were Omnidata Easy Loggers model EL 824-GP. Thermistor rods were constructed by installing thermistors in a plastic rod at fixed intervals noted in the files. Calibration of the thermistors and loggers as a unit was checked in an ice bath with adjustments made where necessary so that the loggers recorded 0º C to within a few hundredths of a degree. Thus, the data are most accurate near the freezing point of pure water.
Power for the loggers was supplied by two 26 amp-hour Gel-Cell batteries with a blocking diode in the circuit. These supply enough power for at least three years of continuous operation if the internal batteries (D cells) in the logger are changed each year. Batteries and loggers were placed in military ammunition containers which were buried in the ground with the lids remaining above ground. The containers were covered by a box insulated with two inches of blue foam.
The thermistor rods were installed in the ground with their bottoms terminating in the permafrost. A large metal washer was bolted to the bottom of the rods, which were frozen in place, to prevent frost heave of the rods.
Temperatures in the air (1.5 m height in a radiation shelter), at the ground surface (using a thermistor in a small metal tube), three temperatures in the active layer, three temperatures at the permafrost table and three temperatures in the permafrost were usually recorded. A logging interval of four hours was used with the logger recording the daily maximum, mean, and minimum air temperatures and the instantaneous and daily mean active layer and permafrost temperatures.
The user is forewarned that some of the thermistors are failing. In most cases, these are indicated by obviously erroneous values, but in some cases the changes are subtle.
Osterkamp, T. E., Temperature measurements in permafrost, Report No. FHWA-AK-RD-85-11, Alaska DOTPF, Fairbanks, AK, 87 pp., January, 1985.
Osterkamp, T. E., Permafrost temperatures in the Arctic National Wildlife Range, Cold Regions Science and Technology, 15 (2), 191-193, 1988.
Osterkamp, T. E., Zhang, T., and Romanovsky, V. E., Evidence for a cyclic variation of permafrost temperatures in Northern Alaska, Permafrost and Periglacial Processes, 5,137-144, 1994.
Osterkamp, T.E., and V.E. Romanovsky, Freezing of the active layer on the Coastal Plain of the Alaskan Arctic, Permafrost and Periglacial Processes, 8(1), 23-44, 1997.
Osterkamp, T. E., and V. E. Romanovsky, Evidence for warming and thawing of discontinuous permafrost in Alaska, Permafrost and Periglacial Processes, 10, 17-37, 1999.
Paetzold, R.F., Hinkel, K.M., Nelson, F.E., Osterkamp, T.E., Ping, C.L., and V.E. Romanovsky. 2000. Temperature and Thermal Properties of Alaska Soils. Global Climate Change and Cold Regions Ecosystems. In, Advances in Soil Science. Edited by Lal.R., Kimble J.M., and B.A. Stewart. CRC Press, Boca Raton, Florida.
Romanovsky, V.E. and T.E. Osterkamp, Interannual variations of the thermal regime of the active layer and near-surface permafrost in Northern Alaska, Permafrost and Periglacial Processes, 6, 313-335, 1995.
Romanovsky, V.E., and T.E. Osterkamp, Thawing of the active layer on the coastal plain of the Alaskan Arctic, Permafrost and Periglacial Processes, 8(1), 1-22, 1997.
Serreze, M., Walsh, J.E., Chapin, F.S. III, Osterkamp, T.E., Dyurgerov, M., Romanovsky, V., Oechel, W.C., Morison, J., Zhang, T., and Barry, R.G.. Observational evidence of recent change in the northern high-latitude environment, Climate Change, 46, 159-207, 2000.
Zhang, T., T.E. Osterkamp, and K. Stamnes, Influence of the depth hoar layer of the seasonal snow cover on the ground thermal regime, Water Resour. Res. 32(7), 2075- 2086, 1996.
Zhang, T., T.E. Osterkamp, and K. Stamnes, Some characteristics of the climate in northern Alaska, Arctic and Alpine Res., 28(4), 509-518, 1996.
Zhang, T., T.E. Osterkamp, and K. Stamnes, Effects of climate on the active layer and permafrost in Alaska north of the Brooks Range, Permafrost and Periglacial Processes, 8(1), 45-68, 1997.