This ratchet. I should buy myself one when I decide to retire. They are on isle 7 at work.
The thing about ratchets is that direction lever on top only lets them turn one way. That is the way CO2 works too. Oceans take up some of what is in the atmosphere but that is slow compared to what is released. Oceans take up about 29% of human CO₂ emissions. One ton is absorbed by oceans for every 3.4 tons that humans emit.
To break even humans have to reduce CO2 emissions by 71%, otherwise concentration only increases. The ratchet only turns one way and the level of fubar is permanent. 71% is not going to happen. Even with Trump's help.
No rest for the wicked. Go to the main page and look at the upper right corner. Click the upper-right globe, and then look above the globe on top of the Doomscroll.
The way I watch monthly CO2 shows how much it has changed in a year. Seasonal variation is filtered out. That gold ratchet has 90 clicks to turn a circle. The current annual global warming climate click is at 0.29% and that is the lowest I have seen. The climate ratchet only turns one way. Half a percent of click is more typical.
So a bad harvest this year means a bad harvest next year. There is no backing up.