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TitrePermafrost thermal state in the polar northern hemisphere during the International Polar Year 2007 - 2009: a Synthesis
AuteurRomanovsky, V E; Smith, S L; Christiansen, H H
SourcePermafrost and Periglacial Processes vol. 21, no. 2, 2010 p. 106-116, https://doi.org/10.1002/ppp.689
Année2010
Séries alt.Secteur des sciences de la Terre, Contribution externe 20100028
Documentpublication en série
Lang.anglais
DOIhttps://doi.org/10.1002/ppp.689
Mediapapier; en ligne; numérique
Formatspdf
ProvinceQuébec; Territoires du Nord-Ouest; Yukon; Nunavut
SNRC15; 16; 25; 26; 27; 28; 29; 35; 36; 37; 38; 39; 45; 46; 47; 48; 49; 55; 56; 57; 58; 59; 65; 66; 67; 68; 69; 75; 76; 77; 78; 79; 85; 86; 87; 88; 89; 95; 96; 97; 98; 99; 105; 106; 107; 115; 116; 117; 120; 340; 560
Lat/Long OENS-180.0000 180.0000 90.0000 60.0000
Sujetspergélisol; congélation du sol; glace fossile; températures au sol; analyses thermiques; temperature; géologie des dépôts meubles/géomorphologie; géologie de l'environnement
Illustrationslocation maps; plots
ProgrammeLes sciences de la Terre à l'appui de la caractérisation, à l'échelle nationale, des impacts des changements climatiques sur la masse continentale canadienne, Géosciences de changements climatiques
Résumé(disponible en anglais seulement)
The permafrost monitoring network in the polar regions of the Northern Hemisphere was enhanced during the International Polar Year (IPY), and new information on permafrost thermal state was collected for regions where there was little available. This augmented monitoring network is an important legacy of the IPY, as is the updated baseline of current permafrost conditions against which future changes may be measured. Within the Northern Hemisphere polar region, ground temperatures are currently being measured in about 575 boreholes in North America, the Nordic region and Russia. These show that in the discontinuous permafrost zone, permafrost temperatures fall within a narrow range, with the mean annual ground temperature (MAGT) at most sites being higher than -2°C. A greater range in MAGT is present within the continuous permafrost zone, from above -1°C at some locations to as low as -15°C. The latest results indicate that the permafrost warming which started two to three decades ago has generally continued into the IPY period. Warming rates are much smaller for permafrost already at temperatures close to 0°C compared with colder permafrost, especially for ice-rich permafrost where latent heat effects dominate the ground thermal regime. Colder permafrost sites are warming more rapidly. This improved knowledge about the permafrost thermal state and its dynamics is important for multidisciplinary polar research, but also for many of the 4 million people living in the Arctic. In particular, this knowledge is required for designing effective adaptation strategies for the local communities under warmer climatic conditions.
GEOSCAN ID263372