Structural changes in the shallow and transition branch of the Brewer–Dobson circulation induced by El Niño

Diallo, Mohamadou; Konopka, Paul; Santee, Michelle L.; Müller, Rolf; Tao, Mengchu; Walker, Kaley A.; Legras, Bernard; Riese, Martin; Ern, Manfred; Ploeger, Felix

doi:https://doi.org/10.5194/acp-19-425-2019

Articles | Volume 19, issue 1

https://doi.org/10.5194/acp-19-425-2019

© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Special issue:

The SPARC Reanalysis Intercomparison Project (S-RIP) (ACP/ESSD...

https://doi.org/10.5194/acp-19-425-2019

© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 19, issue 1

Research article

| Highlight paper

|

11 Jan 2019

Research article | Highlight paper |

| 11 Jan 2019

Structural changes in the shallow and transition branch of the Brewer–Dobson circulation induced by El Niño

Mohamadou Diallo, Paul Konopka, Michelle L. Santee, Rolf Müller, Mengchu Tao, Kaley A. Walker, Bernard Legras, Martin Riese, Manfred Ern, and Felix Ploeger

Data sets

Aura Microwave Limb Sounder (MLS) Version 4.2x Level 2 data quality and description document N. J. Livesey, W. G. Read, P. A. Wagner, L. Froidevaux, A. Lambert, G. L. Manney, L. F. Millán Valle, H. C. Pumphrey, M. L. Santee, M. J. Schwartz, S. Wang, R. A. Fuller, R. F. Jarnot, B. W. Knosp, and E. Martinez https://doi.org/10.5194/acp-15-9945-2015

A comprehensive overview of the climatological composition of the Asian summer monsoon anticyclone based on 10 years of Aura Microwave Limb Sounder measurements M. L. Santee, G. L. Manney, N. J. Livesey, M. J. Schwartz, J. L. Neu, and W. G. Read https://doi.org/10.1002/2016JD026408

The ERA-Interim reanalysis: configuration and performance of the data assimilation system D. P. Dee, S. M. Uppala, A. J. Simmons, P. Berrisford, P. Poli, S. Kobayashi, U. Andrae, M. A. Balmaseda, G. Balsamo, Bauer, P. Bechtold, A. C. M. Beljaars, L. van de Berg, J. Bidlot, N. Bormann, C. Delsol, R. Dragani, M. Fuentes, A. J. Geer, L. Haimberger, S. B. Healy, H. Hersbach, E. V. Hólm, L. Isaksen, P. Kållberg, M. Köhler, M. Matricardi, A. P. McNally, B. M. Monge-Sanz,J.-J. Morcrette, B.-K. Park, C. Peubey, P. de Rosnay, C. Tavolato, J.-N. Thépaut, and F. Vitart https://doi.org/10.1002/qj.828

Short summary

This paper assesses the structural changes in the shallow and transition branches of the BDC induced by El Nino using the Lagrangian model simulations driven by ERAi and JRA-55 combined with MLS observations. We found a clear evidence of a weakening of the transition branch due to an upward shift in the dissipation height of the planetary and gravity waves and a strengthening of the shallow branch due to enhanced GW breaking in the tropics–subtropics and PW breaking at high latitudes.