Ozone layer recovery 'pauses' jet stream climate change

March 26, 2020 9:37 AM

The effort to limit the effects of climate change may have already bourne fruit: The Guardian has reported on a paper that claims that the effects of the Montreal Protocol has slowed changes to the southern mid-latitude jet stream. (Nature SharedIt link, requires javascript)

This unintended effect of the effort to halt the growth of the hole in the ozone layer appears to be slowing decades of trends in weather changes, and may have deeper effects on ocean salinity and the patterns of ocean currents. Quoting the paper:

"we demonstrate that stratospheric ozone recovery, resulting from the Montreal Protocol, is the key driver of the pause. Because pre-2000 circulation trends have affected precipitation, and potentially ocean circulation and salinity, we anticipate that a pause in these trends will have wider impacts on the Earth system. Signatures of the effects of the Montreal Protocol and the associated stratospheric ozone recovery might therefore manifest, or have already manifested, in other aspects of the Earth system."

In the Guardian link, the lead author Antara Banerjee cautions though while this is a victory for the Montreal Protocol, the effect may be temporary in the face of increasing CO2 levels:

“There is a tug of war between ozone recovery and increasing CO2. That’s why we are seeing a pause. In the near future, the ozone factor could dominate and the jet stream will move back towards equator. But once the recovery is complete, CO2 could push it southwards again,”

Further reading:
"It's not like there is a Montreal Protocol police." by Cash4Lead
Pyramids puncture pungent ply; perpetrators pinpointed by Jpfed

posted by Eleven (3 comments total)

What really saddens me is that we will likely never see a Montreal protocol again. The machinery of lobbying has become so much more successful and sophisticated since the eighties (witness, Paris climate committments).
posted by smoke at 4:45 PM on March 26, 2020 [2 favorites]

This is really cool! In trying to give my students some tiny bit of hope, I always talk about the Montreal Protocols, about how all the countries of the world came together to solve the problem, and then when our first attempt didn't do enough, they did it again, about how, even today, when new CFC releases are spotted they are tracked down and stopped.

I do it to give them hope. Not because I have that much hope myself, but because I don't want them to give in to despair.
posted by hydropsyche at 4:59 AM on March 27, 2020 [4 favorites]

I just hope that Mangolini's attention never alights upon the Montreal Protocol.
posted by Philofacts at 8:44 AM on March 29, 2020