EGU2020-5899
https://doi.org/10.5194/egusphere-egu2020-5899
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Enhanced transport and mixing of Arctic ozone during SSWs

Alvaro de la Camara1, Marta Abalos1, Peter Hitchcock2, Natalia Calvo1, and Rolando Garcia3
Alvaro de la Camara et al.
  • 1Universidad Complutense de Madrid, Earth Physics and Astrophysics, Madrid, Spain (acamarai@ucm.es)
  • 2Department of Earth and Atmospheric Sciences, Cornell University, Ithaca NY, USA
  • 3National Center for Atmospheric Research, Boulder CO, USA

The extreme disruptions of the wintertime stratospheric circulation during sudden stratospheric warmings (SSW) have important effects on tracer concentrations through alterations in transport and mixing properties. In this presentation we will examine the dynamics that control changes of Arctic ozone during the life cycle of SSWs, providing a quantitative analysis of both advective transport and mixing of Arctic ozone. We use output from four ensemble members (60 years each) of the Whole Atmospheric Community Climate Model, and also use reanalysis and satellite data for validation purposes. The composite evolution of ozone displays positive mixing ratio anomalies up to 0.5 – 0.6 ppmv above 550 K (∼50 hPa) around the central warming date and negative anomalies below (-0.2 to -0.3 ppmv), consistently in observations, reanalysis and model.

Our analysis shows a clear temporal offset between ozone eddy transport and diffusive ozone fluxes. The initial changes in ozone are mainly driven by isentropic eddy fluxes linked to enhanced wave drag responsible for the SSW. The recovery of climatological values in the aftermath of SSWs is slower in the lower than in the upper stratosphere, and is driven by the competing effects of cross-isentropic motions (which work towards the recovery) and isentropic mixing (which delays the recovery). These features are enhanced in strength and duration during sufficiently deep SSWs, particularly those also labeled as Polar-night Jet Oscillation (PJO) events. It is found that SSW-induced ozone concentration anomalies below 600 K (∼40 hPa), as well as total column estimates, persist around one month longer in PJO than in non-PJO warmings.

How to cite: de la Camara, A., Abalos, M., Hitchcock, P., Calvo, N., and Garcia, R.: Enhanced transport and mixing of Arctic ozone during SSWs, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5899, https://doi.org/10.5194/egusphere-egu2020-5899, 2020

Display materials

Display file

Comments on the display material

AC: Author Comment | CC: Community Comment | Report abuse

Display material version 2 – uploaded on 05 May 2020, no comments
I have added a slide showing results on the behavior of Arctic ozone anomalies during PJO SSWs
Display material version 1 – uploaded on 30 Apr 2020, no comments