Role of equatorial waves and convective gravity waves  in the 2015/16 quasi-biennial oscillation disruption

Kang, Min-Jee; Chun, Hye-Yeong; Garcia, Rolando R.

doi:https://doi.org/10.5194/acp-20-14669-2020

Articles | Volume 20, issue 23

https://doi.org/10.5194/acp-20-14669-2020

© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/acp-20-14669-2020

© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 20, issue 23

Research article

|

02 Dec 2020

Research article |

| 02 Dec 2020

Role of equatorial waves and convective gravity waves in the 2015/16 quasi-biennial oscillation disruption

Min-Jee Kang, Hye-Yeong Chun, and Rolando R. Garcia

Supplement

https://doi.org/10.5194/acp-20-14669-2020-supplement

Data sets

MERRA-2 inst3_3d_asm_Nv: 3D, 3-hourly, instantaneous, model-level, assimilation, assimilated meteorological fields, version 5.12.4 GMAO - Global Modeling and Assimilation Office https://doi.org/10.5067/WWQSXQ8IVFW8

ERA-Interim, 6-hourly, instantaneous, model-level, analysis ECMWF - European Centre for Medium-Range Weather Forecasts https://doi.org/10.1002/qj.828

GPM DPR (Gridded Convective Stratiform Heating) L3 1.5 hours 0.5 degree x 0.5 degree V06 GPM - Global Precipitation Measurement Science Team https://doi.org/10.5067/GPM/DPRGMI/CSH/3G/06

TRMM (TMPA) Precipitation L3 1 day 0.25 degree x 0.25 degree V7 GES DISC - Goddard Earth Sciences Data and Information Services Center https://doi.org/10.5067/TRMM/TMPA/DAY/7

Short summary

In winter 2015/16, the descent of the westerly quasi-biennial oscillation (QBO) jet was interrupted by easterly winds. We find that Rossby–gravity and inertia–gravity waves weaken the jet core in early stages, and small-scale convective gravity waves, as well as horizontal and vertical components of Rossby waves, reverse the wind sign in later stages. The strong negative wave forcing in the tropics results from the enhanced convection, an anomalous wind profile, and barotropic instability.