Extended Abstract (140K)16.7
Trends and variations in South Pacific island and ocean surface temperatures
Chris K. Folland, Hadley Centre, Met Office, Bracknell, Berkshire, United Kingdom; and M. J. Salinger, N. Jiang, and N. A. Rayner
We analyse temperature variability and trends in the South Pacific using data from 40 island stations and optimally interpolated sea surface (SST) and night marine air temperature (NMAT) data. The latter data set contains improved corrections for changes in the height of thermometer screens as ships have become larger. We analyse island and collocated SST and NMAT time series for four large regions which have been corrected for artificial changes in variance due to changes in the availability of constituent island stations. We also provide objective estimates of uncertainty in the SST data. It is shown that annual and seasonal surface ocean and island air temperatures have increased in the South Pacific in geographically-varying ways. The South Pacific Convergence Zone (SPCZ) is also shown to play a pivotal role in both the variability and trends in all three data sets. Trends in the island and marine data show reasonable consistency, with distinctly different patterns of multidecadal change in the four regions examined. However, a notable inconsistency is a lack of warming in NMAT relative to SST in one of the tropical regions since about 1990, echoing a recently published result that shows this effect in some other tropical oceanic regions. Finally these regional trends are compared to worldwide temperature changes.
Session 16, Interdecadal and Longer Term Climate Variability II
Friday, 28 March 2003, 8:30 AM-11:45 AM
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