Multiple symptoms of total ozone recovery inside the Antarctic vortex during austral spring

• Published in: Atmospheric Chemistry and Physics
• Main Authors: Pazmino, Andrea, Godin-Beekmann, Sophie, Hauchecorne, Alain, Claud, Chantal, Khaykin, Sergey, Goutail, Florence, Wolfram, Elian, Salvador, Jacobo, Quel, Eduardo
• Other Authors: STRATO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL), Centro de Investigaciones en Láseres y Aplicaciones Buenos Aires (CEILAP), Consejo Nacional de Investigaciones Científicas y Técnicas Buenos Aires (CONICET)-Instituto de Investigaciones Científicas y Técnicas para la Defensa (CITEDEF), Universidad Nacional de San Martin (UNSAM)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2018
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; Antarc*; Antarctic
• Online Access: https://hal.science/hal-02344066; https://hal.science/hal-02344066/document; https://hal.science/hal-02344066/file/2018_Pazmino_acp-18-7557-2018.pdf; https://doi.org/10.5194/acp-18-7557-2018

International audience The long-term evolution of total ozone column inside the Antarctic polar vortex is investigated over the 1980-2017 period. Trend analyses are performed using a multilinear regression (MLR) model based on various proxies for the evaluation of ozone interannual variability (heat flux, quasi-biennial oscillation, solar flux, Antarctic oscillation and aerosols). Annual total ozone column measurements corresponding to the mean monthly values inside the vor-tex in September and during the period of maximum ozone depletion from 15 September to 15 October are used. Total ozone columns from the Multi-Sensor Reanalysis version 2 (MSR-2) dataset and from a combined record based on TOMS and OMI satellite datasets with gaps filled by MSR-2 (1993-1995) are considered in the study. Ozone trends are computed by a piece-wise trend (PWT) proxy that includes two linear functions before and after the turnaround year in 2001 and a parabolic function to account for the saturation of the polar ozone destruction. In order to evaluate average total ozone within the vortex, two classification methods are used, based on the potential vorticity gradient as a function of equivalent latitude. The first standard one considers this gradient at a single isentropic level (475 or 550 K), while the second one uses a range of isentropic levels between 400 and 600 K. The regression model includes a new proxy (GRAD) linked to the gradient of potential vorticity as a function of equivalent latitude and representing the stability of the vor-tex during the studied month. The determination coefficient (R 2) between observations and modelled values increases by ∼ 0.05 when this proxy is included in the MLR model. Highest R 2 (0.92-0.95) and minimum residuals are obtained for the second classification method for both datasets and months.