CLIMATE WATCH - Where are we headed?

Where are we headed, climate-wise?

It's now a choice of difficult outcomes or very very difficult (or add even more "verys" if the response is totally inadequate)

Temperatures would stabilise "over a human lifetime" if CO2 levels stop rising. They don't decline quickly, but there is a very slow downward drift over a very long time. However, all IPCC scenarios show 1.5 being overtaken at some point between around 2030 and 2040 - we've wasted too much time to do better than that - the "Denial Decades".

Note that the stabilising of temperature implies EITHER all burning of fossil fuel stops, OR if some is still burned, every bit of CO2 produced is accounted for in a real process of sequestration.




Stopping the rise in CO2 also begins to stabilise the water cycle, so rain etc doesn't get a lot worse (it'll be pretty bad by then)

As for coastal areas - the Earth's ice masses are not even in equilibrium with the temperature we have now, and certainly not with whatever temperature we might stop at - sea level will continue to rise in any scenario, long after any point at which we level the CO2 graph, for centuries at least. This means eg that most of the biggest cities on Earth have to defend or retreat over time. We have triggered what geologists call a marine transgression.

My source is this article by Professor Peter Thorne, one of the hundreds of scientists who produced the IPCC report published in August 2021 (IPCC AR6 WG1):

https://www.rte.ie/brainstorm/2021/0809/1239772-ipcc-report-2021-key-takeaways/

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