If You Don’t Like The New England
Weather, Wait A Hundred Years
UNH Scientist’s Unique Climate Model Predicts Big Changes
for the Region’s Weather and Plant Life
Contact: David Sims
Institute for the Study of Earth, Oceans, and Space
Jan. 26, 2006
DURHAM, N.H. -- New England’s weather is so mercurial that,
it has often been noted, if you don’t like it, wait a minute.
These days, in the era of climate change and global warming, waiting
a bit longer – like a few score decades – will bring
not only a modest shift in the region’s weather but a wholesale
redefinition of New England’s signature climate and vegetation.
Think American dogwood trees, balmy winters, and periods of torrential
rain followed by drought conditions.
University of New Hampshire research scientist Ming Chen has developed
a one-of-a-kind regional climate model that predicts a progressive
migration of current, indigenous vegetation types northward during
the 21st century, as well as an increase in heavy precipitation
events – with increased periods of drying and flooding across
not just New England but most of the U.S. These predictions assume
that levels of carbon dioxide in the Earth’s atmosphere will
be double those of today as projected from current trends.
Chen, from the Climate Change Research Center at UNH’s Institute
for the Study of Earth, Oceans, and Space, presented her findings
at last month’s 12,000-strong annual meeting of the American
Geophysical Union in San Francisco. Her work is funded by the National
Oceanic and Atmospheric Administration and the U.S. Environmental
Explains Chen, “We know that climate is the most important
driving force for vegetation growth and distribution. With more
and more greenhouse gases in the atmosphere interwoven with natural
climate variability, they’ll work together to change climate
in the future, and this will affect vegetation.”
What’s more, as vegetation changes so will the natural “biogenic” emissions
from trees and other plants creating a feedback that will force
further changes in regional climate and air quality.
Chen adds, “Our model results show that with the climate
change scenario where CO2 will be doubled, higher latitude areas,
northern parts of the hemisphere, become warmer and wetter. Mid-
and lower-latitude areas will experience more precipitation and
vegetation will migrate systematically northward.”
For example, under this climate scenario, today’s largely
treeless expanse around Hudson Bay, Canada will be forested with
Unlike global-scale climate models, which give big-picture views,
Chen’s regional model uses a much finer spatial scale and
takes into account more physical and biological details that play
into the complex atmospheric processes leading to climate change.
Says Robert Talbot, director of the Climate Change Research Center, “This
is one of the very few regional models that has a coupled feedback
between atmospheric processes, land surface physics, and biospheric
interactions. Ming’s model not only predicts physical climate – temperature,
precipitation, and circulation patterns, for example – but
includes the evolving land surfaces and changing vegetation-plant
After putting in the necessary parameters, for example, soil physics,
land use/land cover type, carbon dioxide, and large-scale forcing,
etc., Chen’s model simulated present and future climate.
The present-day results were compared to actual data and agreed
very well. Says Chen, “This gives us confidence in the ability
of the model to simulate complex processes and provides a basis
for believable future predictions.”
Is a model a sure thing, confident in its results or not? No,
“We can’t use a model to precisely regenerate what
really is going on in the atmosphere, and that’s why people
always ask how high a level of confidence you have in your model.
There are lots of uncertainties in a model system, which is caused
by the complex interactions and feedbacks that we don’t understand
completely – but we are working on it."