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” … the freeze killed … in an area encompassing Nebraska, Maryland,
South Carolina, and Texas. Subsequent drought limited regrowth.”
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 Public release date: 3-Mar-2008
American Institute of Biological Sciences
Contact: Holly Menninger
hmenninger@aibs.org
202-628-1500
Will global warming increase plant frost damage?
Widespread damage from 2007 Eastern US spring
freeze attributed to earlier warming
Widespread damage to plants from a sudden freeze
that occurred across the Eastern United States
from 5 April to 9 April 2007 was made worse
because it had been preceded by two weeks of
unusual warmth, according to an analysis
published in the March 2008 issue of BioScience.
The authors of the report, Lianhong Gu and his
colleagues at the Oak Ridge National Laboratory
and collaborators at NASA, the University of
Missouri, and the National Oceanic and
Atmospheric Administration, found that the freeze
killed new leaves, shoots, flowers, and fruit of
natural vegetation, caused crown dieback of
trees, and led to severe damage to crops in an
area encompassing Nebraska, Maryland, South
Carolina, and Texas. Subsequent drought limited
regrowth.
Rising levels of atmospheric carbon dioxide are
believed to reduce the ability of some plants to
withstand freezing, and the authors of the
BioScience study suggest that global warming
could lead to more freeze and thaw fluctuations
in future winters. This pattern is potentially
dangerous for plants because many species must
acclimate to cold over a sustained period.
Acclimation enables them to better withstand
freezes, but unusual warmth early in the year
prevents the process. A cold spring in 1996, in
contrast to the 2007 event, caused little
enduring damage because it was not preceded by
unusual warmth.
The 2007 freeze is likely to have lasting effects
on carbon balance in the region. Plants cannot
resorb nutrients from dead tissue that would
normally be remobilized within the plants during
autumnal senescence, so many nutrients became
less available for plants in 2008. Wildlife is
expected to have suffered harm from lack of food,
and changes to plant architecture could have
long-term implications.
Gu and his colleagues propose that the 2007
spring freeze should not be viewed as an isolated
event, but as a realistic climate-change
scenario. Further study of its long-term
consequences could help refine scenarios for
ecosystem changes as carbon dioxide levels
increase and the climate warms.
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After noon EST on March 3, the full text of the
article will be available for free download
through the copy of this Press Release available
at http://www.aibs.org/bioscience-press-releases/
BioScience is the monthly journal of the American
Institute of Biological Sciences (AIBS).
BioScience publishes commentary and peer-reviewed
articles covering a wide range of biological
fields, with a focus on “Organisms from Molecules
to the Environment.” The journal has been
published since 1964. AIBS is an umbrella
organization for professional scientific
societies and organizations that are involved
with biology. It represents some 200 member
societies and organizations with a combined
membership of about 250,000.
The complete list of research articles in the
March 2008 issue of BioScience is as follows:
Landscape Genetics.
Rolf Holderegger and Helene H. Wagner
Woody Species as Landscape Modulators annd Their
Effect on Biodiversity Patterns.
Moshe Shachak, Bertrand Boeken, Elli Groner,
Ronen Kadmon, Yael Lubin, Ehud Meron, Gidi
Ne’eman, Avi Perevolotsky, Yehoshua Shkedy, and
Eugene Ungar
Adaptive Growth Decisions in Butterflies.
Karl Gotthard
Hope for Threatened Tropical Biodiversity: Lessons from the Philippines.
Mary Rose C. Posa, Arvin C. Diesmos, Navjot S. Sodhi, and Thomas M. Brooks
Using Surrogate Species and Groups for Conservation Planning and Management.
John A. Wiens, Gregory D. Hayward, Richard S. Holthausen, and Michael J. Wisdom
The 2007 Eastern US Spring Freeze: Increased Cold Damage in a Warming World.
Lianhong Gu, Paul J. Hanson, W. Mac Post, Dale P.
Kaiser, Bai Yang, Ramakrishna Nemani, Stephen G.
Pallardy, and Tilden Meyers
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