HR: 09:20h
AN: U31A-05 [Abstracts]
TI: Atmospheric Amplification of Pacific Decadal Variability
AU: * Clement, A
EM: aclement@rsmas.miami.edu
AF: RSMAS, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, United
States
AU: Burgman, R
EM: rburgman@rsmas.miami.edu
AF: RSMAS, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, United
States
AU: Chen, J
EM: jchen@gmao.gsfc.nasa.gov
AF: ESSIC, UMD, NASA/GSFC Code 610.1, Greenbelt, MD 20771-0001, United States
AB:
The patterns of Pacific Decadal Variability (PDV) are now well-documented in sea surface temperature and sea
level pressure. However, the mechanisms that give rise to these patterns are not well-understood. Much of the
focus of previous studies has been on oceanic mechanisms, or ocean coupling to the lower atmosphere. Here
we present evidence that atmospheric feedbacks involving clouds, water vapor and radiation also contribute to
the pattern of PDV. First, a multi-variate index for PDV is constructed from reanalysis datasets. Then, this
timeseries is used to extract the spatial pattern of PDV in several satellite-based observational datasets as well
as surface-based cloud data. These multiple, independent datasets all show physically consistent signals of
atmospheric feedbacks operating in the subtropical Pacific which would amplify the SST and SLP signals. We
hypothesize that these atmospheric feedbacks are initiated as a remote response to changes in convection in the
western tropical Pacific.
DE: 1610 Atmosphere (0315, 0325)
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 3360 Remote sensing
SC: Union [U]
MN: 2007 Joint Assembly