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NEISA Publications and Reports
NEISA Publications
Bradbury, J.A., Keim, B.D., Wake, C.P. (2003)
The influence of regional storm tracking and teleconnections on winter precipitation in the northeastern United States.
Annals of the American Association of Geographers, 93(3), 544-556.
Abstract
Secular changes in regional storm tracking are examined as physical mechanisms for observed teleconnections
between the New England hydroclimate and four predictor variables: the Southern Oscillation Index, the North
Atlantic Oscillation, the Pacific Decadal Oscillation, and regional sea-surface temperatures. The main modes of
New England winter precipitation, snowfall, and cyclone variability are resolved using varimax rotated principal
component analysis. The first rotated principal component of regional cyclone variability defines an out-of-phase
relationship between marine versus continental cyclone activity and is statistically linked with the Southern
Oscillation, the Pacific Decadal Oscillation, and precipitation in northern New England. Also, El Nino winters
generally accompany a slight increase in southern New England precipitation. The second cyclone rotated principal
component, defining an inverse relationship between cyclone occurrences along the East Coast and cyclone
occurrences along the northern boundary of the Gulf Stream, is well correlated with regional precipitation
and snowfall, demonstrating the significance of marine storm tracking as a control on New England winter hydroclimatic
variability.
Extreme North Atlantic Oscillation conditions are linked with distinct regional storm tracking patterns such that
northwestern New England experiences fewer cyclones during negative NorthAtlantic Oscillation winter months.
Statistical relationships between sea-surface temperatures and principal modes of regional cyclone occurrences are
also noteworthy; however, more work is needed to assess the utility of sea-surface temperatures in the development
of future seasonal forecasts. Also, confirming earlier findings, cool sea-surface temperature conditions are shown
to accompany both drier conditions inland and greater winter snowfall totals in southern coastal regions.
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