It's also closely correlated with this not very happy decision put in place in 2020 [1]:

> On 1 January 2020, a new limit on the sulphur content in the fuel oil used on board ships came into force, marking a significant milestone to improve air quality, preserve the environment and protect human health.

well we can stick planes in the upper atmosphere and sprinkle sulfur around to get some cooling, but it'll get worse before then. gonna be interesting.