Impact of the quasi-biennial oscillation on predictability of the Madden–Julian oscillation
Impact of the quasi-biennial oscillation on predictability of the Madden–Julian oscillation
复制标题
准两年一次的振荡对马登-朱利安振荡的可预测性的影响
DOI：
10.1007/s00382-016-3392-0
复制
发表时间：
2017
期刊：
影响因子：
4.6
通讯作者：
Y. Lim
中科院分区：
文献类型：
--
作者：
A. Marshall;H. Hendon;S. Son;Y. Lim
在准两年振荡（QBO）的东风相期间，北半球冬季的Madden-Julian振荡（MJO）比西风相期间强，50 hPa的QBO纬向风导致MJO活动增强约1个月。使用30年的POAMA耦合模型预测系统的回顾性预测，我们表明，这加强了MJO活动在东风QBO阶段转化为改善预测的MJO及其对流异常在整个热带印度洋-太平洋地区约8天的提前时间相对于西风QBO阶段。这些改进的预测技巧的结果不仅从这样一个事实，即预测初始化与较强的MJO事件，如发生在QBO东风阶段，有更大的技能，但也从更持久的行为的MJO类似的初始振幅在QBO东风阶段相比，QBO西风阶段。因此，QBO是一个尚未开发的亚季节可预测性来源，可以为改善全球气候预测提供机会。
The Madden–Julian oscillation (MJO) during boreal winter is observed to be stronger during the easterly phase of the quasi-biennial oscillation (QBO) than during the westerly phase, with the QBO zonal wind at 50 hPa leading enhanced MJO activity by about 1 month. Using 30 years of retrospective forecasts from the POAMA coupled model forecast system, we show that this strengthened MJO activity during the easterly QBO phase translates to improved prediction of the MJO and its convective anomalies across the tropical Indo-Pacific region by about 8 days lead time relative to that during westerly QBO phases. These improvements in forecast skill result not just from the fact that forecasts initialized with stronger MJO events, such as occurs during QBO easterly phases, have greater skill, but also from the more persistent behaviour of the MJO for a similar initial amplitude during QBO easterly phases as compared to QBO westerly phases. The QBO is thus an untapped source of subseasonal predictability that can provide a window of opportunity for improved prediction of global climate.