Coupling between leading modes in the troposphere-stratosphere interaction

对流层-平流层相互作用中主模之间的耦合

基本信息

批准号：
16540400
负责人：
ITOH Hisanori
金额：
$ 2.37万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2006
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16540400/
关键词：
interaction between the troposphere and stratosphere North Atlantic Oscillation Pacific-North American Oscillation annular mode non-uniform zonal field sudden warming independent component predictability 気象学気候変動非帯状基本場プラネタリー波太平洋

项目摘要

Studies about the stratosphere have been performed from the framework of the zonal mean and deviations from it, and their interaction. However, there are many cases that cannot be explained from this framework, and thereby a new framework is needed. It is the framework of time mean (non-uniform zonal field) and deviations from it. The present study is the first comprehensive research from this framework. In particular, no numerical study from this standpoint has been done, therefore this research is the first in the world.Data analyses about the coupling between the troposphere and stratosphere show the followings : The Pacific-North American pettern (PNA) in the troposphere vertically propagates into the stratosphere, causing the wavenumber 1 (W1) pattern. The dominance of the PNA in the troposphere via the excitation of the W1 mode amplifies the annular mode in the stratosphere. In some cases, this coupling causes sudden warmings. These sequences are clearly different from the AO.Next, by using numerical models, we successfully simulate phenomena in which dominant wavenumbers are different between the troposphere and stratosphere. For this success, a non-uniform zonal field is indispensable. Furthermore, the coupling from the PNA in the troposphere via W1 to the AM in the stratosphere can be simulated by a time integration model.We further proceed to the study about the reality of dominant modes in the troposphere. The conclusion is that although the North Atlantic Oscillation (NAO) and PNA are independent, dominant oscillations in the troposphere, the AO apparently appears due to the spatial correlation of the NAO and PNA. This conclusion verifies our approach that the PNA and NAO are treated in the troposphere.The predictability of the sudden warming is also studied. As a result, we show that sudden warmings caused by wavenumbers 2 or 3 are more difficult in their prediction than those caused by wavenumber 1.

关于平流层的研究是从区域平均值及其偏差及其相互作用的框架中进行的。但是，有很多情况无法从该框架中解释，因此需要一个新的框架。它是时间平均值（不均匀的纬向场）及其偏差的框架。本研究是该框架的首次全面研究。特别是，从这个角度完成的数值研究尚未完成，因此这项研究是世界上的首次研究。数据分析对流层和平流层之间的耦合显示了以下内容：对流层中太平洋 - 北美宠物（PNA）在对流层中垂直倾向在平流层中倾斜，从而导致WaveMumber 1（W1（W1）模式。通过W1模式的激发，PNA在对流层中的优势会放大平流层的环形模式。在某些情况下，这种耦合会导致突然的变暖。这些序列与AO.NEXT显然不同，通过使用数值模型，我们成功地模拟了对流层和平流层之间主要波数不同的现象。为了获得这一成功，一个不均匀的区域场是必不可少的。此外，可以通过时间整合模型来模拟对流层通过W1到AM的耦合。我们进一步研究对流层中主要模式的现实。结论是，尽管北大西洋振荡（NAO）和PNA是独立的，在对流层中占主导地位，但AO显然是由于NAO和PNA的空间相关性而出现的。这个结论验证了我们在对流层中处理PNA和NAO的方法。还研究了突然变暖的可预测性。结果，我们表明，波数2或3引起的突然的升温在预测中比波数1所引起的更难。