TITLE:
Regional Analysis of NASA Satellite Greenness Trends for Ecosystems of Arctic Alaska
AUTHORS:
Christopher Potter
KEYWORDS:
MODIS EVI, Arctic, Tundra, Wetlands, Wildfire, Alaska
JOURNAL NAME:
International Journal of Geosciences,
Vol.5 No.9,
August
27,
2014
ABSTRACT:
Trends in
the growing season MODerate resolution Imaging Spectroradiometer (MODIS)
Enhanced Vegetation Index (EVI) time-series were analyzed for the period from
2000 to 2010 to understand landscape-level patterns of vegetation change in
ecosystems of arctic Alaska. We compared datasets for vegetation cover types,
wetland cover classes, wildfire boundaries since the 1940s, permafrost type,
and elevation to identify the most likely combination of factors driving
regional changes in habitat quality and ecosystem productivity. Approximately
57% of all arctic ecosystem areas in Alaska were detected with significant (p 2) were detected with
significant positive growing season EVI trends. The vast majority of the arctic
Alaska region detected with significant positive growing season EVI trends was
classified as upland tundra cover, although non-forested wetlands (marshes,
bogs, fens, and floodplains) were co-located on 8% of that area. Herbaceous
wetlands were co-located on 55% of the total area detected with significant
negative growing season EVI trends, mostly on the arctic coastal plain and
foothills. This evidence supports the hypothesis that temperature (warming) has
markedly enhanced the rates of upland tundra vegetation growth across most of
arctic Alaska over recent years.