Development of Kyushu University Atmosphere-Ocean General Circulation Model and Research of Climate

九州大学大气-海洋环流模型的开发与气候研究

• 批准号: 63460045
• 负责人: MIYAHARA Saburo
• 金额: $ 3.84万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-63460045/
• 关键词: ENSO; coupled ocean-atmosphere disturbance; El Nino; La Nina; oceanic heat content in western Pacific; intraseasonal oscillation; 西風バ-スト; エル・ニ-ニョ; 大気海洋結合優乱; 季節内擾乱; 西太平洋暖水; エル・ニーニョ; 南方振動; 西風バースト; 大気海洋結合モデル; 海洋熱容量

The objective of this project is to develop the Kyushu University Atmosphere-Ocean general circulation model, and to investigate the short term climatic changes such as El nino and ENSO. The research of this project has been done by two different methods.At first, in order to understand the theoretical background of the coupled ocean-atmosphere dynamics, a simplified atmosphere-ocean coupled model is constructed by using Anderson-McCreary type ocean model and Gill type atmosphere model. Several numerical simulations have been done to investigate the necessary condition for generating the Elnino. It is found that the high oceanic heat content in the westem Pacific and the westerly burst over the western Pacific are the necessary condition for the generation of the El nino. Some numerical integrations have also been done to simulate the ENSO cycle. The model used in these integrations consists of a limited ocean surrounded by lands imitating the Pacific Ocean. An external land heating we … More st of the Pacific is added to simulate the land heating associated with the monsoon. The repetitious generation of the coupled disturbance has nothing to do with the linear model of Hirst (1988) as well as off-equatorial Rossby waves. It is perfectly determined by the amplitude of the external land heating. The mass budget analysis demonstrates that the change of zonal wind direction in the western Pacific, which is due to relative importance between the external land heating and the heating associated with the previous coupled disturbance, modulates the oceanic heat content relevant to the origin of the following coupled disturbance. This mechanism gives the oscillation between two stable equilibria (La Nina and El Nino), which are very different from those described in Battisti (1988), Schopf and Suarez (1987), and Zebiak and Cane (1987). Despite lots of model limitations, the present results seem to be compatible with the recent analyses of the air-sea-land system in the western Pacific.A numerical experiment has been performed using a coupled ocean-atmosphere model in order to examine possible relationships between the atmospheric intraseasonal oscillation and the air-sea coupled interannual disturbance. The model is composed of a T21 atmospheric general circulation model and a simple ocean model. When the ocean is kept motionless with a fixed SST, intraseasonal oscillation is reproduced in the atmosphere. When the ocean is replaced by the active one, the intraseasonal oscillation becomes rather sporadic both in space and time over the warm ocean region produced by the ocean-atmosphere interaction. The mean structure of this warm SST region is very similar to that obtained by the simple coupled ocean-atmosphere model. However, The coupled disturbance in this model has a multi-scale structure having both intraseasonal and interannual modes. Less

本项目的目标是开发九州大学大气-海洋环流模式，并研究厄尔尼诺和ENSO等短期气候变化。本课题的研究主要采用了两种不同的方法：首先，为了了解海气耦合动力学的理论背景，利用Anderson-McCreary型海洋模式和Gill型大气模式建立了一个简化的海气耦合模式。为了研究厄尔尼诺现象产生的必要条件，进行了几次数值模拟。结果表明，西太平洋海洋热含量高和西太平洋西风爆发是厄尔尼诺产生的必要条件。一些数值积分也被用来模拟ENSO循环。在这些整合中使用的模型包括一个有限的海洋，周围环绕着模仿太平洋的陆地。一种外置式地面供暖系统， ...更多信息 太平洋的ST被添加来模拟与季风相关的陆地加热。耦合扰动的反复产生与Hirst（1988）的线性模式以及离赤道Rossby波无关。它完全由外部陆地加热的幅度决定。质量收支分析表明，西太平洋纬向风向的变化，是由于外部陆地加热和前一次耦合扰动加热的相对重要性，调制了与下一次耦合扰动起源有关的海洋热含量。这一机制在两个稳定平衡（拉尼娜和厄尔尼诺）之间产生振荡，这与Battisti（1988）、Schopf和苏亚雷斯（1987）以及Zebiak和Cane（1987）所描述的非常不同。尽管存在许多模式的局限性，但本文的结果似乎与最近对西太平洋海气陆系统的分析是一致的。为了研究大气季节内振荡与海气耦合年际扰动之间的可能关系，利用一个海气耦合模式进行了数值试验。该模式由T21大气环流模式和简单海洋模式组成。当海表温度保持不变时，大气中会产生季节内振荡。当海洋被活跃的海洋所取代时，海洋-大气相互作用所产生的暖海洋区的季节内振荡在空间和时间上都变得相当零星。这一暖SST区的平均结构与简单海气耦合模式的结果非常相似。然而，该模式中的耦合扰动具有多尺度结构，既有季节内模态，也有年际模态。少

项目成果

Y.Masumoto and T.Yamagata: "On the origin of a warm ENSO in the western Pacific" Jour.Meteorol.Soc.Japan. in press. (1991)

Y.Masumoto 和 T.Yamagata：“西太平洋温暖 ENSO 的起源”Jour.Meteorol.Soc.Japan。

升本 順夫: "季節変動と考慮したENSOシミュレ-ション" 月刊海洋. 21. 497-501 (1989)

Juno Masumoto：“考虑季节性波动的 ENSO 模拟”月刊 Kaiyo。21. 497-501 (1989)

T.Yamagata and Y.Masumoto: "A simple ocean-atmosphere coupled model of the origin of a wam ENSO event" Phil.Trans.R.Soc.Lond.A329. 225-236 (1989)

T.Yamagata 和 Y.Masumoto：“wam ENSO 事件起源的简单海洋-大气耦合模型”Phil.Trans.R.Soc.Lond.A329。

T.Yamagata;Y.Masumoto: Philosophical Transactions of Royal Society of London. (1989)

T.Yamagata；Y.Masumoto：伦敦皇家学会哲学汇刊。

Y.Masumoto and T.Yamagata: "On the origin of a warm ENSO in the western Pacific" Jour.Meteorol.Soc.Japan. (1991)

Y.Masumoto 和 T.Yamagata：“西太平洋温暖 ENSO 的起源”Jour.Meteorol.Soc.Japan。