Relationships of inter-American rainfall to tropical Atlantic and Pacific SST variability

• Main Author: David B. Enfield
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1996
• Subjects: Pacific; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.469.7628; http://nml.yonsei.ac.kr/front/bbs/paper/obs-1/CLM-OBS_1996-1_Enfield.pdf

tropical Abstract. Area-averaged anomalies of sea surface temperature (SSTA) and rainfall, developed from large scale data sets, have been used to explore the relative importance of Pacific versus Atlantic SST variability for inter-American (50øS- 50øN) cli-mate variability at interannual time scales. SSTA in the tropi-cal Pacific and tropical North Atlantic are comparably related to rainfall north of 15øS, with clear associations distributed be-tween the southeastern United States (US)in the north and northern South America in the south. Although NINO3 ex-plains 25 % of the variance of the North Atlantic SSTA index, the rainfall correlations with North Atlantic SSTA are for the most part opposite in sign to those with NINO3. Hence, a sig-nificant part of the Atlantic SSTA probably has a direct asso-ciation with rainfall, rather than being merely an indirect proxy for Pacific ENSO linkages. In contrast to the North At-lantic, South Atlantic SSTA appear to be only related to rain-fall in northeast (NE) Brazil. The entire region between Vene-zuela and NE Brazil appears to be sensitive to both the ITCZ and to antisymmetric configurations of SSTA across the ITCZ, in a manner consistent with the relationships between SST, surface wind and surface wind divergence fields, and with previ-ous studies.