Oceanography The Official Magazine of
The Oceanography Society
Volume 32 Issue 02

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Volume 32, No. 2
Pages 42 - 49

Observations of Large-Scale Rainfall, Wind, and Sea Surface Salinity Variability in the Eastern Tropical Pacific

Stephen C. Riser Jie YangRobert Drucker
Article Abstract

We examine profiling float-based measurements of rainfall, wind speed, and near-surface salinity in the eastern tropical Pacific Ocean collected during the SPURS-2 field program. The data show large-scale meridional and zonal variability in these quantities, with considerable variability near the Intertropical Convergence Zone (ITCZ). The eastern tropical Pacific data show strong, intermittent, near-surface, low-salinity events driven by rainfall along the ITCZ that generally do not occur elsewhere in the tropical Pacific. The float salinity data suggest that low-salinity surface water can be entrained 50 m or more into the mixed layer from mid-summer to early in the following calendar year, although the annual periods of strong wind and high precipitation do not coincide. Many of the low-salinity anomalies observed during the SPURS-2 program appear to result from strong, transient storms generated by atmospheric convection along the ITCZ that move across the region.


Riser, S.C., J. Yang, and R. Drucker. 2019. Observations of large-scale rainfall, wind, and sea surface salinity variability in the eastern tropical Pacific. Oceanography 32(2):42–49, https://doi.org/10.5670/oceanog.2019.211.


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