edu.ucar.opensky::articles:22699 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-25T15:33:21.722972 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7tm7cpz Large impacts, past and future, of ozone-depleting substances on Brewer-Dobson circulation trends: A multi-model assessment 2019-05-30T00:00:00Z publication https://n2t.org/ark:/85065/d7tm7cpz https://doi.org/10.1029/2018JD029516 Polvani, Lorenzo author Wang, L. author Abalos, M. author Butchart, N. author Chipperfield, M. author Dameris, M. author Deushi, M. author Dhomse, S. author Jöckel, P. author Kinnison, Douglas E. author Michou, M. author Morgenstern, O. author Oman, L. author Plummer, D. author Stone, K. author UCAR/NCAR - Library publisher Substantial increases in the atmospheric concentration of well-mixed greenhouse gases (notably CO2 ), such as those projected to occur by the end of the 21st century under large radiative forcing scenarios, have long been known to cause an acceleration of the Brewer-Dobson circulation (BDC) in climate models. More recently, however, several single-model studies have proposed that ozone-depleting substances might also be important drivers of BDC trends. As these studies were conducted with different forcings over different periods, it is difficult to combine them to obtain a robust quantitative picture of the relative importance of ozone-depleting substances as drivers of BDC trends. To this end, we here analyze—over identical past and future periods—the output from 20 similarly forced models, gathered from two recent chemistry-climate modeling intercomparison projects. Our multimodel analysis reveals that ozone-depleting substances are responsible for more than half of the modeled BDC trends in the two decades 1980–2000. We also find that, as a consequence of the Montreal Protocol, decreasing concentrations of ozone-depleting substances in coming decades will strongly decelerate the BDC until the year 2080, reducing the age-of-air trends by more than half, and will thus substantially mitigate the impact of increasing CO2 . As ozone-depleting substances impact BDC trends, primarily, via the depletion/recovery of stratospheric ozone over the South Pole, they impart seasonal and hemispheric asymmetries to the trends which may offer opportunities for detection in coming decades. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright 2019 Author(s). This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivative 4.0 International license. None eng geoscientificInformation