Using a combination of tree ring estimates of drought variably of the
last thousands years along with the state of art climate models simulations
of the next hundred years. We've been studying drought try to understand
what affect global warming and climate change will have on drought
in the western United States, over the next hundred years. If you
think about the current on going droughts, such as the drought in California
the drought in the southwest, the, even the historical dust bowl drought of the
1930s. these are natural occurring droughts that lasted on the order of
or will last on the order of several years and some cases even
a decade. What our projections shows is that these, in the future we can
expect droughts that will last 20, 30, 40 years, even exceeding
the duration of the long term intense mega droughts that characterized
the really arid time period known as the mid-evil climate anomaly
These droughts are likely to have major implications and major stresses
on water resource use in the United States. Because
there longer droughts than really anybody has experienced in the entire history of the United States.
An while much of the work are based on computer model simulations
these computer models really represent the best, our best
understanding of how the climate system works. They are tested very extensively
against observations. An at the end of the day, they are the only tool we really have
to investigate future climate change.
We expect that these droughts are going to begin sometime in the middle of the 21st century.
They are going to present potently a very large management challenge
for agricultural, eco-systems and
people in western north America.