- 著者
- Yanjie Li Jin Feng Jianping Li Sen Zhao
- 出版者
- Meteorological Society of Japan
- 雑誌
- SOLA (ISSN:13496476)
- 巻号頁・発行日
- vol.14, pp.121-125, 2018 (Released:2018-09-04)
- 参考文献数
- 25
- 被引用文献数
- 1
Rossby wave propagation theory is reviewed under two kinds of non-uniform basic flows: the zonal mean (ZM) and horizontally non-uniform (HN) flows in this study. The diagrams in the wavenumber domain for stationary and non-stationary waves embedded in the ZM flow are given and discussed in comparison with previous studies. Then a circle diagram in the group velocity domain for waves embedded in the HN flow is derived from the formulas in forms of three vectors: the wavenumber, background wind and gradient of basic-state absolute velocity. Given the basic state, we can identify the maximum and minimum magnitude of group velocity and its departure from the background wind. These results provide insights into Rossby wave propagation behaviors in the real atmosphere.
- 著者
- Baosheng Li Ruiqiang Ding Jianping Li Yidan Xu Jiao Li
- 出版者
- Meteorological Society of Japan
- 雑誌
- SOLA (ISSN:13496476)
- 巻号頁・発行日
- vol.14, pp.52-56, 2018 (Released:2018-04-26)
- 参考文献数
- 33
- 被引用文献数
- 5
The connection between the predictability of the East Asian summer monsoon (EASM) and El Niño-Southern Oscillation (ENSO) has recently attracted widespread attention. Of particular importance is the effect of El Niño and La Niña on EASM predictability. In this paper, the signal-to-noise ratio (SNR) method is used to analyze reanalysis data, and the results show that the EASM potential predictability intensity is much stronger under El Niño forcing than that under La Niña forcing. Meanwhile, the asymmetric response of EASM predictability remains within the Community Atmosphere Model (CAM) simulations. The EASM predictability is quantitatively determined using the nonlinear local Lyapunov exponent (NLLE) method. The EASM predictability limit under El Niño forcing is longer than that for La Niña forcing. Two monsoon indices are used to measure the EASM, the predictability limits of which perform differently because of their particular definitions. However, the asymmetric response of EASM predictability to El Niño and La Niña can be verified using observational data and model experiments.