Olsen said that, contrary to the Instagram post, scientists"have never claimed that reaching 350 will lead to a detrimental loss in global food production."
"The current atmospheric CO2 concentration is 419 ppm. It is rising by 2 ppm each year, so if emissions continue unabated, the levels mentioned in the post is easily reached -- at least for 600 ppm," he said, noting that is the level at which such effects will begin., a research scientist in Canada studying carbon-climate interactions, told AFP about 50 percent of human-caused emissions have stayed in the atmosphere.
"The rest have been absorbed by the land and the ocean. Had land and ocean not provided us with this ecosystem service, the current concentration of CO2 would have been much higher," he said August 1, describing the Instagram post as"cherry-picking information." Higher CO2 levels help plants photosynthesize more, Arora said. But if plants face extreme conditions -- such as water shortage, heat and drought -- they cannot absorb the gas in the same capacity, regardless of how much is in the atmosphere.
, a lead author of an IPCC chapter on food and ecosystem products, told AFP that"elevated CO2 cannot be dissociated from changes in temperatures and precipitation extremes and variability."