Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Oral

A (Atmospheric and Hydrospheric Sciences) » A-AS Atmospheric Sciences, Meteorology & Atmospheric Environment

[A-AS07] Stratosphere-troposphere Processes And their Role in Climate

Wed. May 23, 2018 9:00 AM - 10:30 AM A07 (Tokyo Bay Makuhari Hall)

convener:Shingo Watanabe(Japan Agency for Marine-Earth Science and Technology), Yoshio Kawatani(Japan Agency for Marine-Earth Science and Technology), Takashi Sekiya(国立研究開発法人 海洋研究開発機構, 共同), Kaoru Sato(Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo), Chairperson:Kawatani Yoshio

9:00 AM - 9:15 AM

[AAS07-01] Hindcasts of the 2016 Disruption of the Stratospheric Quasi-biennial Oscillation

*Shingo Watanabe1, Kevin Hamilton2, Scott Osprey3, Yoshio Kawatani1, Eriko Nishimoto1 (1.Japan Agency for Marine-Earth Science and Technology, 2.International Pacific Research Center, Univ. of Hawaii, 3.NCAS-Climate, Univ. of Oxford)

Keywords:disruption of quasi-biennial oscillation, hindcast, high-vertical resolution global climate model

In early 2016 the quasi-biennial oscillation in tropical stratospheric winds was disrupted by an anomalous easterly jet centered at ~40 hPa, a development that was completely missed by all operational extended range weather forecast systems. This event and its predictability are investigated through ensemble hindcasts using a global model notable for its sophisticated representation of the upper atmosphere. Key to prediction of this event is simulating the slowly evolving mean winds in the winter subtropics that provide a waveguide for Rossby waves propagating from the winter hemisphere. Its association to the strong El Nino condition in 2015 is also investigated by changing sea surface temperatures.