The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking |
| |
作者单位: | YAN BangLiang CMSR,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China |
| |
基金项目: | Supported by the National Key Programme of China for Developing Basic Science(Grant No. 2004CB418300) and the Prediction of the Variability of Ocean Climate and Prediction of Global Sea Waves (Grant No. 2006BAC03B03) |
| |
摘 要: | The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking is ex-amined by using a mixed-mode model. The results show that the positive feedback process of the ef-fects of the seasonal variation of the upwelling mean on the Kelvin wave is the mechanism of the locking of the event mature phase to the end of the calendar year. The memory of the Rossby waves for the sign-shifting of the sea surface temperature anomaly from positive to negative 6 months before the cold peak time is the other mechanism of the locking of the La Nia event mature phase to the end of the calendar year. The results here are different from previous ones which suggest that the balance between cold and warm trends of sea surface temperature anomaly is the mechanism involved. The cold trend is caused by the upwelling Kelvin wave from upwelling Rossby wave reflected at the western boundary, excited by the westerly anomaly stress over the central Pacific and amplified by the seasonal variation of the coupled strength in its way propagating westward. The warm trend is caused by the Kelvin wave forced by the western wind stress over the middle and eastern equatorial Pacific. The cause of the differences is due to the opposite phase of the seasonal variation of the upwelling mean to that in the observation and an improper parameterization scheme for the effects of the seasonal varia-tion of the upwelling mean on the ENSO cycle in previous studies.
|
收稿时间: | 1 December 2006 |
修稿时间: | 19 March 2007 |
The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking |
| |
Authors: | Yan BangLiang |
| |
Institution: | CMSR, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China |
| |
Abstract: | The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking is examined by using a mixed-mode model. The results show that the positive feedback process of the effects of the seasonal variation of the upwelling mean on the Kelvin wave is the mechanism of the locking of the event mature phase to the end of the calendar year. The memory of the Rossby waves for the sign-shifting of the sea surface temperature anomaly from positive to negative 6 months before the cold peak time is the other mechanism of the locking of the La Niña event mature phase to the end of the calendar year. The results here are different from previous ones which suggest that the balance between cold and warm trends of sea surface temperature anomaly is the mechanism involved. The cold trend is caused by the upwelling Kelvin wave from upwelling Rossby wave reflected at the western boundary, excited by the westerly anomaly stress over the central Pacific and amplified by the seasonal variation of the coupled strength in its way propagating westward. The warm trend is caused by the Kelvin wave forced by the western wind stress over the middle and eastern equatorial Pacific. The cause of the differences is due to the opposite phase of the seasonal variation of the upwelling mean to that in the observation and an improper parameterization scheme for the effects of the seasonal variation of the upwelling mean on the ENSO cycle in previous studies. |
| |
Keywords: | Kelvin wave Rossby wave interaction between atmosphere and sea positive feedback |
本文献已被 CNKI 万方数据 SpringerLink 等数据库收录! |