Office of Biological and
Environmental Research Weekly Report
March 30, 2009
China Cloud and Aerosol Data Available from DOE ARM Mobile Facility. Data collected by the Atmospheric Radiation Measurement
(ARM) Mobile Facility (AMF) in Shouxian,
China, during the Aerosol
Indirect Effects Study in China
from May through December 2008 are now in the ARM Data Archive. This experiment
was anchored by the AMF in Shouxian and included an
additional instrumented site to the east at Lake Taihu
and two instrumented sites to the north. Data from the two northern sites are
being processed and will be available in the next week. These extensive
measurements of clouds, aerosols, radiation, and precipitation will help
scientists to examine the role of aerosols in affecting the regional climate
and atmospheric circulation across the Pacific Rim. These data are also important for improving
and evaluating the global climate models.
Media Interest: No.
Contact: Wanda Ferrell,
SC-23.1, (301) 903- 3281
What Caused the mid-1970s
Climate Anomaly? Evaluating the Role of Humans Versus
Nature. Observations indicate there
was a significant shift in the mid-1970s from cooler to warmer tropical Pacific
sea surface temperatures (SSTs). The
cause of these basin-wide SST anomalies with global impacts has been a topic of
scientific debate. In a recent paper, DOE-funded scientists at the National Center
for Atmospheric Research in Boulder,
Colorado and the Program for
Climate Model Diagnosis and Intercomparison at
Lawrence Livermore National Laboratory analyzed observations and climate model
simulations to investigate the 1970s climate anomaly. Results show the 1970s climate shift in the
Pacific SST was a combination of warming due to human-produced greenhouse gases
superimposed on what was likely a natural decadal fluctuation of the Pacific
climate system. Determining the relative
roles of human influence versus naturally-occurring internal variability is
important for understanding climate fluctuations that have already been
observed. This knowledge is also
important for the new field of decadal climate prediction with the challenge of
estimating regional climate anomalies over the next several decades with
contributions from both inherent climate variability and external forcing from
human activities.
Reference: Meehl, G. A., A. Hu, and B.D. Santer, 2009: The mid-1970s climate shift in the Pacific
and the relative roles of forced versus inherent decadal variability, J. Climate, 22, 780--792.
Media
Interest: No
Contact: Anjuli Bamzai, SC-23.1, (301) 903-0294