| Title | Response of permafrost in Canada to a changing climate |
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| Author | Lewkowicz, A G; Smith, S L ; Burn, C R |
| Source | Proceedings, Our Warming Planet, IAMAS-IAPSO-IACS Joint Assembly MOCA-09/Processus, Le réchauffement de notre planète, AIMSA-AISPO-AISC assemblée conjointe, MOCA-09; by MOCA-09 Committee; 2009. |
| Links | MOCA-09 website
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| Year | 2009 |
| Alt Series | Earth Sciences Sector, Contribution Series 20080649 |
| Meeting | IAMAS-IAPSO-IACS Joint Assembly MOCA-09; Montreal; CA; July 19-29, 2009 |
| Document | book |
| Lang. | English |
| Media | paper |
| Subjects | environmental geology; Nature and Environment; permafrost; climatic fluctuations |
| Program | Climate Change Geoscience |
| Released | 2009 01 01 |
| Abstract | The impacts of climate change on permafrost, a key component of the cryosphere in Canada, are not always obvious or direct. However, results from a network of permafrost monitoring sites, largely
developed by the Geological Survey of Canada and enlarged with university researchers and other partners during the International Polar Year, show that warming of permafrost has occurred. In the Yukon, new boreholes in mountainous terrain indicate
that ground temperatures are affected by both elevation and local topography. These observations are linked to results from a network of about 90 air and ground surface temperature measurement sites across the Territory which demonstrate
the
importance and strength of air temperature inversions in reversing lapse rates in the winter months, and reducing them to very low values on an annual basis. In the southern part of the Yukon, a resurvey of sites along the Alaska Highway that were
examined in 1964 shows that substantial loss of permafrost has occurred over the past 45 years, but
that thin permafrost has persisted at some sites. On Herschel Island in the Beaufort Sea, measurements and modeling suggest that permafrost
temperatures have increased substantially since the end of the nineteenth century. In the Mackenzie Valley, significant warming has been observed along the Norman Wells pipeline route over the past 25
years. These results illustrate that
permafrost response to past and future climate change are complex and depend upon antecedent ground temperatures, ice contents and vegetation, as well as on the magnitude of the climatic change. |
| GEOSCAN ID | 226361 |
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