GLOBE-Net, August 14, 2012 - Researchers at
Oregon State University have found that the chronic drought that
struck western North America from 2000 to 2004 was the strongest in
800 years, but predict that such drought conditions may become the
"new normal" in coming decades.
In a
study published in Nature Geoscience, a group of ten
researchers found that the prolonged drought cut carbon
sequestration by 51 percent in a huge tract of western North
America. The drought caused vegetation to whither, releasing carbon
dioxide into the atmosphere and accelerating global warming as a
result.
The multi-year drought from 2000 to 2004 was unlike any drought
in centuries, according to tree-ring data. However, climate models
suggest that the precipitation patterns that led to this severe
drought are likely to persist far into the future.
In a somber conclusion, the scientists suggest that "towards the
latter half of the 21st century the precipitation regime associated
with the turn of the century drought will represent an outlier of
extreme wetness."
Permanent shifts in precipitation patterns pose a threat to BC's
forests. Forests act as a carbon sink, storing carbon above and
below ground, so climate-induced tree mortality has the potential
to release huge volumes of stored carbon.
In their study, the Oregon State University researchers estimate
that "the present mid-latitude carbon sink in western North America
could disappear by the end of the century."
Scientists and policymakers are aware of the threat, and are
acting accordingly. In BC, researchers are looking
to develop drought-resilient forests by identifying trees that are
genetically predisposed to drought-hardiness. (See related
GLOBE-Net article:
Weather shifts have strong implications on forest management and
carbon in BC: UBC.)
Forest managers are considering future climate conditions and
are planting
trees that can survive the climate of fifty or a hundred years
from now. When forests are managed for carbon, the uncertainty of
climate change is addressed by placing generous buffers on forest
carbon credits.
The risk of climate change to forests is severe. But through
modelling, planning, and adaptive management, BC's forests can
hopefully be a part of a climate change solution.
From PICS Climate News Scan - August 14, 2012 - produced
by ISIS at the Sauder School of Business and
the Pacific
Institute for Climate Solutions (PICS). Authors:
Justin Bull, Liz Ferris, James Noble, Tim Shah, Kristina Welch;
Editors: Neil Salmond (ISIS), Joanna Buczkowska (ISIS), James
Tansey (ISIS), Jessica Worsley (PICS), Tom Pedersen (PICS)