JpGU-AGU Joint Meeting 2017

講演情報

[EE] ポスター発表

セッション記号 A (大気水圏科学) » A-OS 海洋科学・海洋環境

[A-OS17] [EE] Climate variations in the Atlantic Ocean and their representation in climate models

2017年5月24日(水) 15:30 〜 17:00 ポスター会場 (国際展示場 7ホール)

コンビーナ:Ingo Richter(JAMSTEC Japan Agency for Marine-Earth Science and Technology)、Noel S Keenlyside(Geophysical Institute Bergen)、Thomas Spengler(University of Bergen)、Carlos R Mechoso(University of California Los Angeles)

[AOS17-P01] Impact of NTA SST on ENSO in a seasonal prediction model

*Woo-Hyun Yang1Jong-Seong Kug1 (1.Pohang University of Science and Technology)

キーワード:North Tropical Atlantic, CFS, ENSO, Seasonal prediction model

Recent studies researched that North Tropical Atlantic (NTA) sea surface temperature (SST) play a role in trigger of ENSO events. In this study, we investigate the impact of SST on ENSO events in seasonal prediction model. NCEP Climate Forecast System (CFS) is a seasonal forecasting model which has reforecasts data for 9 months from initial data. We use 20 ensembles for 27 years (1982 ~ 2008yr) and February initial data which integrate prediction from March to November (9 months). Before analyzing CFS data, we eliminate trend, seasonal cycle and ensemble mean. Same as preceding research, in CFS, there are positive anomalies during boreal spring (March-May, MAM) over the NTA and it brings Gill-type Rossby-wave response over the subtropical eastern Pacific which causes northerly flows with cold anomalous SST. Following month, easterly is over the western Pacific and westerly is over the eastern Pacific during boreal summer (the JJA season). From these, cold SST anomalies develop over the central Pacific like La Nina pattern. As mentioned above, CFS perform about ENSO prediction from NTA well. Even when CFS works well, there are NTA SST difference comparing with observation data. From NTA SST error, we calculate corrected NTA SST and verify that it is improved over the central Pacific on ENSO prediction.