scholarly journals Recent Changes in the Ventilation of the Southern Oceans

Science ◽  
2013 ◽  
Vol 339 (6119) ◽  
pp. 568-570 ◽  
Author(s):  
Darryn W. Waugh ◽  
Francois Primeau ◽  
Tim DeVries ◽  
Mark Holzer
Keyword(s):  
Large Scale ◽  
Ozone Hole ◽  
Atmospheric Gases ◽  
Mode Waters ◽  
Deep Waters ◽  
Antarctic Ozone ◽  
The Antarctic ◽  
The Impact ◽  
Antarctic Ozone Hole ◽  
Southern Oceans

Surface westerly winds in the Southern Hemisphere have intensified over the past few decades, primarily in response to the formation of the Antarctic ozone hole, and there is intense debate on the impact of this on the ocean's circulation and uptake and redistribution of atmospheric gases. We used measurements of chlorofluorocarbon-12 (CFC-12) made in the southern oceans in the early 1990s and mid- to late 2000s to examine changes in ocean ventilation. Our analysis of the CFC-12 data reveals a decrease in the age of subtropical subantarctic mode waters and an increase in the age of circumpolar deep waters, suggesting that the formation of the Antarctic ozone hole has caused large-scale coherent changes in the ventilation of the southern oceans.

scholarly journals Delay in recovery of the Antarctic ozone hole from unexpected CFC-11 emissions

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
S. S. Dhomse ◽  
W. Feng ◽  
S. A. Montzka ◽  
R. Hossaini ◽  
J. Keeble ◽  
...  
Keyword(s):  
Montreal Protocol ◽  
Ozone Hole ◽  
Atmospheric Variability ◽  
Gas Emissions ◽  
Model Simulations ◽  
The Future ◽  
Antarctic Ozone ◽  
The Antarctic ◽  
The Impact ◽  
Antarctic Ozone Hole

AbstractThe Antarctic ozone hole is decreasing in size but this recovery will be affected by atmospheric variability and any unexpected changes in chlorinated source gas emissions. Here, using model simulations, we show that the ozone hole will largely cease to occur by 2065 given compliance with the Montreal Protocol. If the unusual meteorology of 2002 is repeated, an ozone-hole-free-year could occur as soon as the early 2020s by some metrics. The recently discovered increase in CFC-11 emissions of ~ 13 Gg yr−1 may delay recovery. So far the impact on ozone is small, but if these emissions indicate production for foam use much more CFC-11 may be leaked in the future. Assuming such production over 10 years, disappearance of the ozone hole will be delayed by a few years, although there are significant uncertainties. Continued, substantial future CFC-11 emissions of 67 Gg yr−1 would delay Antarctic ozone recovery by well over a decade.

scholarly journals Impact of biogenic very short-lived bromine on the Antarctic ozone hole during the 21<sup>st</sup> century

2016 ◽  
Author(s):  
Rafael P. Fernandez ◽  
Douglas E. Kinnison ◽  
Jean-Francois Lamarque ◽  
Simone Tilmes ◽  
Alfonso Saiz-Lopez
Keyword(s):  
Stratospheric Ozone ◽  
Montreal Protocol ◽  
Ozone Hole ◽  
Hole Area ◽  
Climate Simulations ◽  
Photochemical Decomposition ◽  
Antarctic Ozone ◽  
The Antarctic ◽  
The Impact ◽  
Antarctic Ozone Hole

Abstract. Active bromine released from the photochemical decomposition of biogenic very short-lived bromocarbons (VSLBr) enhances stratospheric ozone depletion. Based on a dual set of 1960–2100 coupled chemistry-climate simulations (i.e. with and without VSLBr), we show that the maximum Antarctic ozone hole depletion increases by up to 14 % when natural VSLBr are considered, in better agreement with ozone observations. The impact of the additional 5 pptv VSLBr on Antarctic ozone is most evident in the periphery of the ozone hole, producing an expansion of the ozone hole area of ~5 million km2, which is equivalent in magnitude to the recently estimated Antarctic ozone healing due to the implementation of the Montreal Protocol. We find that the inclusion of VSLBr in CAM-Chem does not introduce a significant delay of the modelled ozone return date to 1980 October levels, but instead affect the depth and duration of the simulated ozone hole. Our analysis further shows that total bromine-catalysed ozone destruction in the lower stratosphere surpasses that of chlorine by year 2070, and indicates that natural VSLBr chemistry would dominate Antarctic ozone seasonality before the end of the 21st century. This work suggests a large influence of biogenic bromine on the future Antarctic ozone layer.

The discovery of the Antarctic ozone hole

Nature ◽  
2019 ◽  
Vol 575 (7781) ◽  
pp. 46-47 ◽  
Author(s):  
Susan Solomon
Keyword(s):  
Ozone Hole ◽  
Antarctic Ozone ◽  
The Antarctic ◽  
Antarctic Ozone Hole

Ozone loss in Antarctica: the implications for global change

1992 ◽  
Vol 338 (1285) ◽  
pp. 219-226 ◽  
Keyword(s):  
Large Scale ◽  
Stratospheric Ozone ◽  
Field Measurements ◽  
Careful Analysis ◽  
Data Sets ◽  
Ozone Loss ◽  
New Ideas ◽  
Antarctic Ozone ◽  
The Antarctic ◽  
Antarctic Ozone Hole

Although stratospheric ozone loss had been predicted for m any years, the discovery of the Antarctic ozone hole was a surprise which necessitated a major rethink in theories of stratospheric chemistry. The new ideas advanced are discussed here. Global ozone loss has now also been reported after careful analysis of satellite and groundbased data sets. The possible causes of this loss are considered. Further advances require a careful coordination of field measurements and large-scale numerical modelling.

scholarly journals Impact of biogenic very short-lived bromine on the Antarctic ozone hole during the 21st century

2017 ◽  
Vol 17 (3) ◽  
pp. 1673-1688 ◽  
Author(s):  
Rafael P. Fernandez ◽  
Douglas E. Kinnison ◽  
Jean-Francois Lamarque ◽  
Simone Tilmes ◽  
Alfonso Saiz-Lopez
Keyword(s):  
21St Century ◽  
Stratospheric Ozone ◽  
Montreal Protocol ◽  
Ozone Hole ◽  
Community Atmosphere Model ◽  
Hole Area ◽  
Photochemical Decomposition ◽  
Antarctic Ozone ◽  
The Impact ◽  
Antarctic Ozone Hole

Abstract. Active bromine released from the photochemical decomposition of biogenic very short-lived bromocarbons (VSLBr) enhances stratospheric ozone depletion. Based on a dual set of 1960–2100 coupled chemistry–climate simulations (i.e. with and without VSLBr), we show that the maximum Antarctic ozone hole depletion increases by up to 14 % when natural VSLBr are considered, which is in better agreement with ozone observations. The impact of the additional 5 pptv VSLBr on Antarctic ozone is most evident in the periphery of the ozone hole, producing an expansion of the ozone hole area of ∼ 5 million km2, which is equivalent in magnitude to the recently estimated Antarctic ozone healing due to the implementation of the Montreal Protocol. We find that the inclusion of VSLBr in CAM-Chem (Community Atmosphere Model with Chemistry, version 4.0) does not introduce a significant delay of the modelled ozone return date to 1980 October levels, but instead affects the depth and duration of the simulated ozone hole. Our analysis further shows that total bromine-catalysed ozone destruction in the lower stratosphere surpasses that of chlorine by the year 2070 and indicates that natural VSLBr chemistry would dominate Antarctic ozone seasonality before the end of the 21st century. This work suggests a large influence of biogenic bromine on the future Antarctic ozone layer.

scholarly journals On the size of the Antarctic ozone hole

2004 ◽  
Vol 31 (21) ◽  
pp. n/a-n/a ◽  
Author(s):  
Paul A. Newman ◽  
S. Randolph Kawa ◽  
Eric R. Nash
Keyword(s):  
Ozone Hole ◽  
Antarctic Ozone ◽  
The Antarctic ◽  
Antarctic Ozone Hole
Sign in / Sign up

Export Citation Format

Share Document