Because of rising carbon dioxide concentrations in the atmosphere

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plants behave differently when they are exposed to higher atmospheric CO2 levels because CO2 influences the behavior of stomata, the microscopic holes in leaves that allow a leaf to take up CO2. These holes also allow water to evaporate from the leaf, which must be replenished by water supplied to the roots to avoid drying out. With more CO2 in the atmosphere, a plant can afford to have smaller or fewer stomata, thus allowing more photosynthesis for the same amount of water.

The Anti-Humans has been 'raising awareness' (bitching and bellyaching) for decades about two things.

There won't be enough food in the future to feed the increasing global population..
There won't be enough water in the future to meet the needs of the increasing population.

Increasing CO2 concentrations in the air fixes BOTH of those problems very nicely. More food can be grown with less water.

It's a WIN/WIN.

So what do the Anti-Humans propose?

You guessed it..they want to cut back on the amount of CO2 in the air. They want everyone to lower their Carbon Foot Print

In other News
The carbon dioxide level is dangerously low
Atmospheric CO2 Concentrations At 400 PPM Are Still Dangerously Low For Life On Earth

Insane.

The Anti-Humans (the so called Environmentalists, The Democrats, The Progressives, The Socialists, but I repeat myself) are trying to KILL US ALL

If we do what they want us to do, all life on earth will be wiped out.