Antarctic ozone loss in 1979-2010: first sign of ozone recovery

• Published in: Atmospheric Chemistry and Physics
• Main Authors: Kuttippurath, Jayanarayanan, Lefèvre, Franck, Pommereau, Jean-Pierre, Roscoe, H. K., Goutail, Florence, Pazmino, Andrea, Shanklin, J. D.
• Other Authors: STRATO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), British Antarctic Survey (BAS), Natural Environment Research Council (NERC)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; Antarctic; The Antarctic; Antarc*; Antarctica
• Online Access: https://hal.science/hal-00691957; https://hal.science/hal-00691957/document; https://hal.science/hal-00691957/file/acp-13-1625-2013.pdf; https://doi.org/10.5194/acp-13-1625-2013

A long-term ozone loss time series is necessary to understand the evolution of ozone in Antarctica. Therefore, we construct the time series using ground-based, satellite and bias-corrected multi-sensor reanalysis (MSR) data sets for the period 1989-2010. The trends in ozone over 1979-2010 are also estimated to further elucidate its evolution in the wake of decreasing halogen levels in the stratosphere. Our analysis with ground-based observations shows that the average ozone loss in the Antarctic is about −33 to −50% (−90 to −155 DU (Dobson Unit)) in 1989-1992, and then stayed at around −48% (−160 DU). The ozone loss in the warmer winters (e.g. 2002 and 2004) is lower (−37 to −46%), and in the very cold winters (e.g. 2003 and 2006) it is higher (−52 to −55%). These loss estimates are in good agreement with those estimated from satellite observations, where the differences are less than ±3%. The ozone trends based on the equivalent effective Antarctic stratospheric chlorine (EEASC) and piecewise linear trend (PWLT) functions for the vortex averaged ground-based, Total Ozone Mapping Spectrometer/Ozone Monitoring Instrument (TOMS/OMI), and MSR data averaged over September-November exhibit about −4.6 DU yr−1 over 1979-1999, corroborating the role of halogens in the ozone decrease during the period. The ozone trends computed for the 2000-2010 period are about +1 DU yr−1 for EEASC and +2.6 DU yr−1 for the PWLT functions. The larger positive PWLT trends for the 2000-2010 period indicate the influence of dynamics and other basis functions on the increase of ozone. The trends in both periods are significant at 95% confidence intervals for all analyses. Therefore, our study suggests that Antarctic ozone shows a significant positive trend toward its recovery, and hence, leaves a clear signature of the successful implementation of the Montreal Protocol.