Spectral measures and mixed models as valuable tools for investigating controls on land surface phenology in high arctic Greenland
Abstract Background Changes in land surface phenology are of major importance to the understanding of the impact of recent and future climate changes in the Arctic. This paper presents an extensive study from Zackenberg Ecological Research Operations (ZERO) where snow melt, climate and growing seaso...
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ftbiomed:oai:biomedcentral.com:1472-6785-7-9 2023-05-15T14:38:16+02:00 Spectral measures and mixed models as valuable tools for investigating controls on land surface phenology in high arctic Greenland Tamstorf, Mikkel P Illeris, Lotte Hansen, Birger U Wisz, Mary 2007-09-19 http://www.biomedcentral.com/1472-6785/7/9 en eng BioMed Central Ltd. http://www.biomedcentral.com/1472-6785/7/9 Copyright 2007 Tamstorf et al; licensee BioMed Central Ltd. Research article 2007 ftbiomed 2008-01-26T00:11:04Z Abstract Background Changes in land surface phenology are of major importance to the understanding of the impact of recent and future climate changes in the Arctic. This paper presents an extensive study from Zackenberg Ecological Research Operations (ZERO) where snow melt, climate and growing season characteristics of six major high arctic vegetation types has been monitored during 1999 to 2005. We investigate the growth dynamics for dry, mesic and wet types using hand held measurements of far red normalised difference vegetation index (NDVI-FR) and generalized additive mixed models (GAMM). Results Snow melt and temperature are of major importance for the timing of the maximum growth as well as for the seasonal growth. More than 85% of the variance in timing of the maximum growth is explained by the models and similar for the seasonal growth of mesic and wet vegetation types. We find several non-linear growth responses to the environmental variables. Conclusion We conclude that the uses of GAMMs are valuable for investigating growth dynamics in the Arctic. Contrary to several other studies in the Arctic we found a significant decreasing trend of the seasonally integrated NDVI-FR (SINDVI) in some vegetation types. This indicates that although greening might occur wide-spread in the Arctic there are variations on the local scale that might influence the regional trends on the longer term. Article in Journal/Newspaper Arctic Greenland Zackenberg BioMed Central Arctic Greenland |
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Open Polar |
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BioMed Central |
op_collection_id |
ftbiomed |
language |
English |
description |
Abstract Background Changes in land surface phenology are of major importance to the understanding of the impact of recent and future climate changes in the Arctic. This paper presents an extensive study from Zackenberg Ecological Research Operations (ZERO) where snow melt, climate and growing season characteristics of six major high arctic vegetation types has been monitored during 1999 to 2005. We investigate the growth dynamics for dry, mesic and wet types using hand held measurements of far red normalised difference vegetation index (NDVI-FR) and generalized additive mixed models (GAMM). Results Snow melt and temperature are of major importance for the timing of the maximum growth as well as for the seasonal growth. More than 85% of the variance in timing of the maximum growth is explained by the models and similar for the seasonal growth of mesic and wet vegetation types. We find several non-linear growth responses to the environmental variables. Conclusion We conclude that the uses of GAMMs are valuable for investigating growth dynamics in the Arctic. Contrary to several other studies in the Arctic we found a significant decreasing trend of the seasonally integrated NDVI-FR (SINDVI) in some vegetation types. This indicates that although greening might occur wide-spread in the Arctic there are variations on the local scale that might influence the regional trends on the longer term. |
format |
Article in Journal/Newspaper |
author |
Tamstorf, Mikkel P Illeris, Lotte Hansen, Birger U Wisz, Mary |
spellingShingle |
Tamstorf, Mikkel P Illeris, Lotte Hansen, Birger U Wisz, Mary Spectral measures and mixed models as valuable tools for investigating controls on land surface phenology in high arctic Greenland |
author_facet |
Tamstorf, Mikkel P Illeris, Lotte Hansen, Birger U Wisz, Mary |
author_sort |
Tamstorf, Mikkel P |
title |
Spectral measures and mixed models as valuable tools for investigating controls on land surface phenology in high arctic Greenland |
title_short |
Spectral measures and mixed models as valuable tools for investigating controls on land surface phenology in high arctic Greenland |
title_full |
Spectral measures and mixed models as valuable tools for investigating controls on land surface phenology in high arctic Greenland |
title_fullStr |
Spectral measures and mixed models as valuable tools for investigating controls on land surface phenology in high arctic Greenland |
title_full_unstemmed |
Spectral measures and mixed models as valuable tools for investigating controls on land surface phenology in high arctic Greenland |
title_sort |
spectral measures and mixed models as valuable tools for investigating controls on land surface phenology in high arctic greenland |
publisher |
BioMed Central Ltd. |
publishDate |
2007 |
url |
http://www.biomedcentral.com/1472-6785/7/9 |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
Arctic Greenland Zackenberg |
genre_facet |
Arctic Greenland Zackenberg |
op_relation |
http://www.biomedcentral.com/1472-6785/7/9 |
op_rights |
Copyright 2007 Tamstorf et al; licensee BioMed Central Ltd. |
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