Previous research has identified links between tropical
cyclone activity and sea surface temperatures in the tropical
cyclogenesis regions of the North Atlantic and Western
North Pacific. Other work has demonstrated that warming in
these regions is inconsistent with simulated internal
variability. After evaluating the variability of a suite of
climate models on a range of timescales, we use detection
and attribution methods and a suite of 20th century
simulations including anthropogenic and natural forcing to
identify a significant response to external forcing in both
regions during the June–November hurricane season over
the 20th century. We then use separate simulations of the
response to natural and anthropogenic forcing to identify
anthropogenic influence independently of natural influence
in both the Atlantic and Pacific Cyclogenesis Regions.

Last Updated: 2008-08-25