講演情報
[U02-07]Fingerprinting the recovery of Antarctic ozone★Invited Papers
*Peidong Wang1,9、Susan Solomon1、Benjamin D. Santer2,3、Douglas E. Kinnison4、Qiang Fu5、Kane A. Stone1、Jun Zhang4、Gloria L. Manney6,7、Luis F. Millán8 (1.Massachusetts Institute of Technology、2.Woods Hole Oceanographic Institution、3.University of California, Los Angeles、4.National Center for Atmospheric Research、5.University of Washington、6.NorthWest Research Associates、7.New Mexico Institute of Mining and Technology、8.Jet Propulsion Laboratory、9.Stanford University)
キーワード：
Antarctic ozone、Optimal fingerprinting、Internal variability、Detection and attribution
The Antarctic ozone “hole” was discovered in 1985 and is primarily caused by man-made ozone-depleting substances (ODSs). Following reductions of ODSs under the Montreal Protocol, signs of ozone recovery have been reported, based largely on observations and broad yet compelling model-data comparisons. Although such approaches are highly valuable, they do not provide rigorous statistical detection of the temporal and spatial structure of Antarctic ozone recovery in the presence of internal climate variability. Initial-condition large ensembles from fully coupled climate models provide a powerful framework for capturing both natural internal variability and the distinct spatial and temporal patterns of climate responses to external forcings. Such ensembles, though widely used in climate change detection, have rarely been applied to stratospheric ozone studies, which typically rely on multiple linear regression to isolate forced trends. Here we apply a pattern-based detection and attribution method to identify the “fingerprint” of Antarctic ozone recovery as a function of month and height. Using satellite observations together with single-model and multi-model large ensembles, we demonstrate strong pattern similarity between data and model-simulated ozone responses to decreasing ODSs since 2005. This provides robust statistical and physical evidence that ODS reductions under the Montreal Protocol are indeed resulting in the beginning of Antarctic ozone recovery. We also show that present-day ODS forcing has significantly enhanced ozone internal variability during the austral spring compared to preindustrial time, affecting signal detectability and suggesting a potential pathway for external forcing to modulate specific modes of internal climate variability.