Centre de documentation
scientifique

Modelling flow routing in permafrost landscapes with TWI: an evaluation against site-specific wetness measurements / A. Persson in Transactions in GIS, vol 16 n° 5 (October 2012)  

Public [article]  inTransactions in GIS > vol 16 n° 5 (October 2012) . - pp 701 - 713 Titre : Modelling flow routing in permafrost landscapes with TWI: an evaluation against site-specific wetness measurements Type de document : Article/Communication Auteurs : A. Persson, Auteur ; A. Hasan, Auteur ; J. Tang, Auteur ; Petter Pilesjö, Auteur Année de publication : 2012 Article en page(s) : pp 701 - 713 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie [Termes IGN] changement climatique [Termes IGN] dégel [Termes IGN] données lidar [Termes IGN] données localisées 3D [Termes IGN] humidité du sol [Termes IGN] modèle numérique de surface [Termes IGN] pergélisol [Termes IGN] Suède [Termes IGN] tourbe Résumé : (Auteur) In northern peatlands the thawing of permafrost increasing the active layer depth and changing the hydrology may lead to feedbacks in the climate system through changes in the biogeochemistry of carbon. We are examining this association on the Stordalen peatland complex in subarctic Sweden by analyzing a DEM derived from LiDAR-data and the calculated TWI [Topographical Wetness Index]. The DEM, with a spatial resolution of 1 m, and the TWI are evaluated against two seasons of water level measurements from 30 sites in the peatland. The TWI is calculated with a form-based flow routing algorithm which produces a natural flow routing pattern. In permafrost wetlands the topography is the major driver and is very important even though its magnitude is low. Site-specific wetness (SSW) measurements from the sites were compared with the different peatland types that occur in the study area, i.e. fen, internal fen and palsa. The results showed a strong correlation between the TWI and the palsa. The TWI was better at describing general patterns than site-specific hydrology. The evaluation of spatial patterns of TWI against SSW reveal the resolution required to develop the technique to be useful for climate change studies. Numéro de notice : A2012-520 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/j.1467-9671.2012.01338.x Date de publication en ligne : 22/08/2012 En ligne : https://doi.org/10.1111/j.1467-9671.2012.01338.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31966 [article]