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The Ozone layer is on the mend!

Antarctic ozone hole on its way to full recovery! - latest Montreal Protocol scientific assessment confirms the continued recovery of stratospheric ozone.

As indicated in the latest Scientific Assessment of Ozone Depletion: 2018, stratospheric ozone recovery increases are largely ascribed to decreasing atmospheric ozone depleting substances production and consumption levels thanks to global actions taken under the Montreal Protocol. The international agreement has, to date, been signed by 197 countries and continues to guide worldwide efforts to mitigate the health and ecosystem related effects of the issue, as well as monitoring stratospheric ozone recovery measures.


All measures are based on scientific, environmental, and economic information that is provided by the Protocol’s technical panels and scientific assessments. Information given in these reports and those of other global initiatives with similar objectives, such as the IUCN Red List of Ecosystems (RLE), aims to inform governments and other stakeholders in their decision-making progress towards achieving international, pro-ozone layer environmental targets.  

Effects of Ozone depletion on Ecosystems

Depletion of the stratospheric ozone over the Southern Hemisphere has shifted atmospheric circulation patterns, leading to change in regional climate characteristics. It has been reported that these changes have a significant influence during the austral summer and the impacts documented so far for both regional climate and ecosystems key processes include:

Climate shifts

  • A poleward shift in Southern Hemisphere tropospheric circulation (wind patterns), with associated impacts on surface temperature and precipitation.
  • The subtropical edge of the tropical circulation has expanded poleward due to wind circulation, leading to reduced precipitation in mid-latitudes and enhanced precipitation in the subtropics.

Ecosystem impacts

  • Recent occurrences of droughts, floods, and associated ecological disturbances.
  • Changes to growth rates of South American and New Zealand trees, decreased growth of Antarctic mosses and changing biodiversity in Antarctic lakes. 

How can decision-makers benefit from Montreal Protocol and RLE data?

Given the intricate connection that exists between the state of the ozone layer and what happens in Earth’s ecosystems (depending, for example, on an ecosystem’s proximity to the ozone layer´s affected area), stakeholders would benefit from taking into account data made available by both the Montreal Protocol reports and IUCN-RLE’s ecosystem risk assessments when drawing management plans.

The Montreal Protocol can aid decision-makers in figuring out an area’s ozone layer current state, while RLE can contribute by painting a more holistic picture through ecosystem collapse risk assessments that focus on measuring reductions in geographical distribution and degradation of key processes. This will provide a baseline to support better resource use and management decisions.

Looking ahead…

When the Scientific Assessment of Ozone Depletion: 2018 was first presented last week during the 30th Meeting of the Parties to the Montreal Protocol in Quito, Ecuador, authors provided evidence of the Montreal Protocol international treaty’s effectiveness and success since 1987. According to the report, it's estimated that the northern hemisphere and the mid-latitude ozone will recover completely by the 2030s. This followed closely by the southern hemisphere in the 2050s and the polar regions by 2060.

The continued success of the Montreal Protocol depends on the world’s nations continued compliance with its measures. As this and other successful initiatives are progressively embedded in the existing policy mix, it is clear that considering a synergy between data provided by the Montreal Protocol and other initiatives with similar objectives, such as the IUCN Red List of Ecosystems, might also prove to be a useful strategy for decision-makers.



Written by: Lila García and Clara Gómez

Style and format: Lila García and Clara Gómez

Provita Nov 15, 2018


IUCN Red List of Ecosystems


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