axel heiberg

Axel Heiberg Island

Axel Heiberg Island is the 31st largest island in the world and Canada's 7th largest island. According to Statistics Canada , it has an area of 43 178 km² (16,671 square miles). One of the larger members of the Canadian Arctic Archipelago, the island is known for its unusual fossil forests, which date from the Eocene period. Owing to the lack of mineralization in many of the forest specimens, the traditional characterization of "fossilisation" fails for these forests and "mummification" may be a clearer description. It is clear that the Axel Heiberg forest was a high latitude wetland forest.

History of Axel Heiberg Island

Axel Heiberg Island has been inhabited in the past by Inuit people, but was uninhabited by the time it was named by Otto Sverdrup, who explored it around 1900. He named it after Axel Heiberg, manager of the Norwegian Ringnes brewery which sponsored the expedition. Other explorers visited the island during the early 20th century, during which time it was claimed by Norway until 1930. It is now part of Nunavut Territory, Canada. It wasn't until the late 1940s that the island was aerially photographed by the United States Army Air Forces' Operation Polaris. In 1955 two geologists of the Geological Survey of Canada, N.J. McMillan and Souther, traversed the interior as part of Operation Franklin. McMillan's observations of Bunde Glacier, in northwest Axel Heiberg Island, are the earliest glaciological observations on the ground to have found their way into a scientific publication.

In 1959, scientists from McGill University explored Expedition Fiord (previously Sør Fjord or South Fiord) in central Axel Heiberg Island. This resulted in the establishment of the McGill Arctic Research Station constructed 8 km inland from Expedition Fjord in 1960. It consists of a small research hut, a cookhouse and 2 temporary structures that can comfortably accommodate 8-12 persons. The station was busiest during the early 1960s, during which a population of 20 was present. The station is now only used for specific studies during the summer months.

During the summer of 1986, a Canadian expedition headed by Dr James Basinger set out to investigate this very unusual fossil forest. The findings of the expeditions and research have since been popularly reported in Canada

As late as 1999, the preservation of this unique site has been endangered. The unique mummified wood was being used for campfires by unknown persons or taken away by tourists on luxury liners cruising the Arctic Ocean. Every August, passengers from cruise ships arrive to tour the site. Canadian military helicopters have been landing on the most sensitive areas.

American plans have also been in progress to excavate the fossil forest. The issue is not whether research should be carried out, but which country should be principally involved in this pursuit.

The fossil forest, which lies outside the borders of the new Quttinirpaaq National Park(formerly Ellesmere Island National Park) on Ellesmere Island, is unprotected from the damage that visitors can inflict. The future protection of the unique fossil forest on Axel Heiberg Island appears to lie in the hands of the Nunavut government. It is an issue of territorial jurisdiction.

White Glacier is a valley glacier occupying 38.7 km2 in the Expedition Fiord area of Axel Heiberg Island, Nunavut, Canada (longitude -90°50', latitude 79°30'). It extends in elevation from 56 m to 1782 m above sea level, a range which, as noted by Dyurgerov (2002), is exceeded only by Devon Ice Cap in the world list of glaciers with measured mass balance. Sea-level temperature in the Expedition Fiord area averages about -20°C, but the glacier is known to have a bed which is partly unfrozen, at least beneath the valley tongue; ice thickness reaches or exceeds 400 m. Annual precipitation at sea level is very low, about 100 mm a-1. However annual accumulation at higher altitudes is greater, reaching 370 mm a-1 at 2000 m on Müller Ice Cap to the north of White Glacier. Annual ablation at the terminus of the glacier is typically 2000-4000 mm a-1. The equilibrium-line altitude averages 970 m, with a range from 470 m to 1400 m, and mass balance is well correlated with equilibrium-line altitude.

In the photograph, note the irregular terrain in front of the glacier terminus. This is White Glacier's terminal and recessional moraine. Its maximum extension, marking the advance of the glacier in response to the cooling of the Little Ice Age, was reached not earlier than the late 18th century, and more probably at the beginning of the 20th century. The amount of retreat to the date of the photograph, 1980, is about 400 m, and since then there has been another 100 m of recession. There is now evidence that the retreat of the terminus, previously at about 5 m a-1, is decelerating (Cogley et al. 1996a; Cogley and Adams 2000). However, the advance of the adjoining Thompson Glacier continues; the two terminuses have been in contact since at least the time of the earliest photographs in 1948, but, although they remain distinguishable, White Glacier has become a tributary of Thompson Glacier.

Photo credit: Rob Hember The mass-balance record of White Glacier has most recently been reassessed by Cogley et al. (1995, 1996b). The mass-balance "normal", for 29 years of record from 1960 to 1991, was -100±48 mm a-1, with extreme annual values of -780 mm a-1 and 350 mm a-1. No statistically significant trend can be found in the mass-balance series, but a principal finding of the reassessment is that physically plausible values of trend would not be detectable with current stake-based methods of measurement: errors in estimates of annual mass balance are of the order of 200-250 mm a-1. However the average balance during the 1990s, -278±126 mm a-1, was the most negative of the four decadal averages now available.

On the other hand, in 1998, White Glacier's mass balance was -229 mm a-1, slightly above the decadal average. This year, globally, was the warmest since weather records began and very probably the warmest of the last millennium (Houghton et al. 2001). It was also the year of most negative mass balance in the much shorter global glaciological record (see Global Glaciology) - but evidently not on Axel Heiberg Island.

White Glacier has been the subject of many papers in the glaciological literature since 1960 (Ommanney 1987; Cogley 1999a). A recent example is Cogley (1999b). Notable earlier studies include those of Blatter (1987) and Müller (1962). The latter was the source of a now-classical diagram elaborating and illustrating the concept of "glacier facies".

References

  • Blatter, H., 1987, "On the thermal regime of an arctic valley glacier: a study of White Glacier, Axel Heiberg Island, N.W.T., Canada", Journal of Glaciology, 33, 200-211.
  • Cogley, J.G., 1999a, "Axel Heiberg Island: Selected References on Glaciology", Trent Technical Note 99-2, Department of Geography, Trent University, Peterborough. 9p.
  • Cogley, J.G., 1999b, "Effective sample size for glacier mass balance", Geografiska Annaler, 81A(4), 497-507.
  • Cogley, J.G., W.P. Adams, M.A. Ecclestone, F. Jung-Rothenhäusler and C.S.L. Ommanney, 1995, Mass Balance of Axel Heiberg Island Glaciers, 1960-1991 -- A Reassessment and Discussion, Science Report 6, National Hydrology Research Institute, Environment Canada, Saskatoon. 178p.
  • Cogley, J.G., M.A. Ecclestone and W.P. Adams, 1996a, Fluctuations of the terminuses of White and Thompson Glaciers, Axel Heiberg Island, Eastern Snow Conference Proceedings, 53, 83-94.
  • Cogley, J.G., W.P. Adams, M.A. Ecclestone, F. Jung-Rothenhäusler and C.S.L. Ommanney, 1996b, "Mass balance of White Glacier, Axel Heiberg Island, N.W.T., Canada, 1960-91", Journal of Glaciology, 42, 548-563.
  • Cogley, J.G., and W.P. Adams, 2000, "Photographic resources for monitoring glacier fluctuations on Axel Heiberg Island", Arctic, 53(3), 248-259.
  • Dyurgerov, M.B., 2002, Glacier Mass Balance and Regime: Data of Measurements and Analysis, Occasional Paper 55, Institute of Arctic and Alpine Research, University of Colorado. 268p. Boulder, Colorado.
  • Houghton, J.T., and 7 others, 2001, Climate Change 2001: The Scientific Basis. Cambridge University Press, Cambridge. 881p.
  • Müller, F., 1962, "Zonation of the accumulation area of the glaciers of Axel Heiberg Island, N.W.T.", Journal of Glaciology, 4, 302-310.
  • Ommanney, C.S.L., 1987, Axel Heiberg Island bibliography. In Occasional Paper 12, 5-55, Department of Geography, Trent University, Peterborough, Canada. (Also Miscellaneous Paper 2, Axel Heiberg Island Research Reports, McGill University, Montreal.)

Population

The island is uninhabited except for one small seasonal research station operated by McGill University.

References

Further reading

  • Adams, Peter. Field Research on Axel Heiberg Island, N.W.T., Canada Bibliographies and Data Reports ; with Appendices of Data from the McGill Subarctic Research Station, Shefferville, P.Q. Sherbrooke, Québec: Centre for Northern Studies and Research, McGill University, 1987.
  • Jackson, M P A, and J C Harrison. 2006. "An Allochthonous Salt Canopy on Axel Heiberg Island, Sverdrup Basin, Arctic Canada". Geology. 34, no. 12: 1045.
  • Kuc, M. Bryogeography of Expedition Area, Axel Heiberg Island, N.W.T., Canada. Bryophytorum bibliotheca, Bd. 2. Lehre: Cramer, 1973. ISBN 3768209121
  • LePage, B. A. 2001. "New Species of Picea A. Dietrich (Pinaceae) from the Middle Eocene of Axel Heiberg Island, Arctic Canada". Botanical Journal of the Linnean Society. 135: 137-167.
  • Liptzin, Daniel. 2006. "A Banded Vegetation Pattern in a High Arctic Community on Axel Heiberg Island, Nunavut, Canada". Arctic, Antarctic, and Alpine Research. 38, no. 2: 216.
  • Maag, Hans Ulrich. Ice Dammed Lakes and Marginal Glacial Drainage on Axel Heiberg Island, Canadian Arctic Archipelago. Montreal: McGill University, 1969.
  • Redpath, Bruce B. Seismic Investigations of Glaciers on Axel Heiberg Island. 1964.
  • Ricketts, Brian David. Delta Evolution in the Eureka Sound Group, Western Axel Heiberg Island The Transition from Wave-Dominated to Fluvial-Dominated Deltas. Ottawa: Energy, Mines, and Resources Canada, 1991. ISBN 0660138441
  • Vandermark, D., J. A. Tarduno, and D. B. Brinkman. 2006. "Late Cretaceous Plesiosaur Teeth from Axel Heiberg Island, Nunavut, Canada". Arctic. 59, no. 1: 79-82.
  • Yang, H., Huang, Y., Leng, Q, LePage, B.A. and Williams C.J. 2005. "Biomolecular preservation of Tertiary Metasequoia fossil Lagerstatten revealed by comparative pyrolysis analysis". Review of Palaeobotany and Palynology, 134: 237-256.

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