Recent research has pointed to the existence of
natural, generation-scale (15-40 year) climate phases, or regimes,
related to the influence of the Atlantic and Pacific Oceans
[1-9]. These
decadal-to-multidecadal (D2M) swings in ocean temperatures have had
significant impacts on air temperature, rainfall and severe storms in
North America, Europe and Africa [10-16].
Most importantly, D2M climate
regimes have impacted the frequency of extreme events, such as droughts
[12], floods, hurricanes
[16] and environmentally linked health
problems. In Florida, D2M climate regimes are associated with a 40%
change in the water supply for Lake Okeechobee, which is the main
reservoir for South Florida
(Figure 1). The natural D2M climate regimes
have alternately camouflaged and exaggerated the effects of
anthropogenic climate change
[10], and are being studied, among other
things, in order to reduce the uncertainty in the magnitude of the
anthropogenic influence. Modern computer models used for D2M studies -
unlike those used for the more short-lived El Niño - are not yet capable
of predicting future shifts in the D2M climate regimes. However, thanks
to recent tree-ring reconstructions of past D2M regime shifts over a
half-millennium or more [17,18],
we now have the ability to project the
probability of future regime shifts with useful accuracy. With further
collaboration between climate scientists and risk managers, such as
water management engineers, we hope this new area of study will lead to
the development of an increasingly useful suite of decision support
tools for water, health, agriculture and disaster mitigation. In this
project we aim to develop such tools for a specific area of high
priority for NOAA and the nation: water supply management.
