1. The signal of La Niña in wave transport
- Author
-
Baonan Sun, Y.F. Shi, Kejian Wu, and Yongzeng Yang
- Subjects
Global and Planetary Change ,Water transport ,Future studies ,010504 meteorology & atmospheric sciences ,Anomaly (natural sciences) ,Westerlies ,Management, Monitoring, Policy and Law ,010502 geochemistry & geophysics ,01 natural sciences ,Swell ,Extreme weather ,La Niña ,Sea surface temperature ,Climatology ,Computers in Earth Sciences ,Geology ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
La Nina phenomena have significant impact on extreme weather and marine disasters in China. Large-scale water transport is one of the primary factors affecting the development of La Nina events; however, the contribution of swell transport from the Southern Ocean to the sea surface temperature anomaly (SSTA) in the eastern equatorial Pacific (EEP) has been ignored in previous studies. Through various statistical techniques, this study used seven sets of satellite altimeter and reanalysis data to reveal the relationship between swell transport and La Nina. Based on the characteristics of significant SSTA changes in the Nino 3 region (5°S–5°N, 90°–150°W) following an El Nino event, two cases of La Nina and non-La-Nina were defined. Wave transport in the first case presents an anomaly to the north of the 30°S section, i.e., cold water carried by swell transport to the EEP increases prior to the onset of a La Nina event. However, the characteristics of swell transport in the non-La-Nina scenario are contrary to the first case. Wave transport anomalies in the two considered cases produce sufficient and necessary conditions for the development of La Nina and non-La-Nina events. In addition, the impact of swell transport from the westerlies on La Nina events is confirmed further based on heat flux calculations. Wave transport has considerable effect on SSTA variability in the EEP; therefore, it should not be neglected in future studies.
- Published
- 2018