HR: 17:50h
AN: GC54B-10 [Abstracts]
TI: Impact of volcanic forcing on tropical temperatures over the last four centuries
AU: * Wilson, R
EM: rob.wilson@ed.ac.uk
AF: University of Edinburgh, School of GeoSciences,
Grant Institute,
Edinburgh University,
West Mains Road, Edinburgh, EH9 3JW, United Kingdom
AU: * Wilson, R
EM: rob.wilson@ed.ac.uk
AF: Tree-Ring Laboratory, Lamont-Doherty Earth Observatory
Palisades, New York, 10964, United States
AU: D'Arrigo, R
EM: rdd@ldeo.columbia.edu
AF: Tree-Ring Laboratory, Lamont-Doherty Earth Observatory
Palisades, New York, 10964, United States
AB:
Current knowledge of the impact of volcanism and other radiative forcings on the past climate of the tropics is
limited, yet critically important for understanding abrupt climatic change over this region and the globe. Here we
combine 19 high-resolution, well-dated records from tree rings, corals and ice cores into an annual composite
time series that provides a view of volcanism's impact on tropical sea surface temperatures (SSTs) during the
past four centuries. We find an association between explosive tropical volcanic eruptions and cold reconstructed
temperatures, although the cooling is spatially variable across the tropics. Severe conditions following the
unknown and Tambora, Indonesia eruptions of the early 1800s indicate that this was the coldest sustained
period of the Little Ice Age in the tropics. The tropical impact of the 1600 Huaynaputina, Peru event appears much
weaker than at higher latitudes, but the number of tropical proxies for this period is very low. The most severely
cold reconstructed year is 1731 and may be related to several eruptions at this time, or to an unknown event. Our
results have important implications for understanding the sensitivity of the tropics to natural and anthropogenic
forcing.
DE: 1605 Abrupt/rapid climate change (4901, 8408)
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 3305 Climate change and variability (1616, 1635, 3309, 4215, 4513)
DE: 3344 Paleoclimatology (0473, 4900)
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting