Spring Ozone Hole detected on 2020-04-04

In the news today in Finland is told that a Spring ozone hole similar to that usual over Antarctica has been detected today for the first time over the Arctic. Data is from sounding in the north of Finland. News says: 90% of stratospheric ozone reduction at an altitude of 18 km. Current ozone column of 271 DU compared to the usual 416 DU at this location and time of the year. I found the news only in Finnish, published a bit over an hour ago. Anyway, current UV-Index and 2-days forecast is available at https://en.ilmatieteenlaitos.fi/uv-index. This page covers the whole planet and has links to detailed maps for different regions.    

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CFCs, the ozone layer and global change

Most people reading this blog are likely to be aware of the role of CFCs in the thinning of the ozone layer and its extreme manifestation the “ozone hole”. (If not you will find explanations here and here and ozone depletion maps here, and information on the Montreal protocol here and here.) An article by Prof. Nigel Paul published in the The Conversation highlights the success of the protocol. However, what fewer people know is that CFCs are potent “greenhouse gases”, and a recent article discusses why of all measures taken up to day, what has most significantly contributed to slowing-down global warming is the Montreal protocol. In my view, to a large extent this just shows how little progress has been achieved in reducing emissions of other “greenhouse gases” like carbon dioxide. A recent article in The Economist highlights this.

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