Premium
Observational evidence of an intensifying hydrological cycle in northern Canada
Author(s) -
Déry Stephen J.,
HernándezHenríquez Marco A.,
Burford Jason E.,
Wood Eric F.
Publication year - 2009
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2009gl038852
Subject(s) - bay , climatology , streamflow , arctic , annual cycle , period (music) , environmental science , water cycle , discharge , physical geography , oceanography , geology , geography , drainage basin , ecology , physics , cartography , acoustics , biology
Trends and variability in the 1964–2007 annual streamflow for 45 rivers spanning 5.2 × 10 6 km 2 of northern Canada are investigated. Discharge averages 1153 km 3 yr −1 with a standard deviation of 71.4 km 3 yr −1 and coefficient of variation (CV Q ) of 6.2% over the 44‐year period. A trend analysis reveals a recent (1989–2007) 15.5% increase in the annual flows owing to much‐above average values recorded over the past decade. Trends in CV Q computed from 11‐year moving windows of annual streamflows exhibit spatially coherent signals with increasing variability across most of northern Canada, excluding some rivers with outlets to the Labrador Sea and eastern James Bay. For the period of interest, 46% and 30% of the available gauged area and river discharge, respectively, experienced detectable increases in variability. This provides observational evidence of an intensifying hydrological cycle in northern Canada, consistent with other regions of the pan‐Arctic domain.