The paper ( https://www.nature.com/articles/s41586-023-06321-z.pdf https://www.nature.com/articles/s41586-023-06321-z.pdf ) seems to be written in "whistling in

The paper ( https://www.nature.com/articles/s41586-023-06321-z.pdf https://www.nature.com/articles/s41586-023-06321-z.pdf ) seems to be written in "whistling in the dark" mode where coastal pollution and algae blooms, which covered ~8.6% of the ocean surface in 2020 ( https://www.worldatlas.com/oceans/study-reveals-why-coastal-algae-blooms-now-cover-over-8-6-of-total-ocean-surface-area.html https://www.worldatlas.com/oceans/study-reveals-why-coastal-... )... are studiously unmentioned. They have to tie it all instead somehow to 'warming' and more distantly to CO2 in atmosphere and be professionally 'mystified' by any other causes, to unlock the funding achievement to use the term Climate Change in their paper and make it citeable. If they don't know what may be causing it, they might browse the lines of their own computer model that predicted it and see what they say.