Plants use CO2 to make sugars. I think. If CO2 levels increase, won't the plants just use it up?

Answer 1

Some plants (but not all) will grow faster but no where near fast enough to offset our output. The carbon we are releasing at a very fast pace was originally built up over millions of years of plants that died and were buried. We have released in just 100 years or so many millions of years worth of carbon accumulations. Also, as several others have pointed out we are cutting trees faster than they are growing all over the world, which is clearly not helping. The most important carbon sinks are the oceans and plankton, which does absorb a big fraction of what we release every year. If we stop releasing CO2 these natural sinks will eventually absorb all the extra CO2 floating around in the atmosphere but it will take a few hundred years to come back down to historically normal values.

Answer 2

Studies have shown that with increased CO2 levels in the atmosphere that crop yield could be reduced by as much as 40%. This is because the plants will be getting less Nitrogen.

Answer 3

Plants don't just use an infinite amount of CO2, and if they did, then they could create an over-abundance of O2, which could be just as bad. At any rate, CO2 isn't the only threatening gas that we put into the atmosphere, so the question is moot.

Answer 4

There are only a limited number of plants and they can only process as much as they need to survive... More CO2 doesn't mean that there'll be more plants to use it. (Although I have heard that many weedy species tend to grow faster with more CO2 as compared to common agricultural/food crops, which means more herbicides...)

And then you have the problems of urban sprawl (more plants being paved over) and deforestation in senstive areas (such as CO2 draining rainforests) meaning fewer plants to process the increasing CO2 levels...

Answer 5

Not if we keep cutting down the plants. And, the plants can't use the CO2 as fast as it can trap in heat and cause a green-house effect.

Answer 6

No. Since the concentration is increasing, it is a sign plants are not using it up as fast as it is added. Plants seem to use up about 5-10 ppm of 300+ ppm each summer. Then in the winter, it gets added back.

Answer 7

No.
Part of the reason CO2 levels are increasing so rapidly is that human development has reduced the amount of plant life, such as rain forests or temperate forests (US & Europe).

Answer 8

They will not let me grow Hemp in my front yard will they. Not to smoke just to replace a few trees in the rainforest. OSB (orientated strand board) a replacement for plywood could be made 10 times as strong by usin g hemp fibers compared to using wood chips. I was a carpenter before a scientist.

Answer 9

no - the plant can process a fixed amount of CO2, and we keep cutting them.

Answer 10

where do you think carbon dioxide comes from? animals. plants need carbon dioxide and give off oxygen, animals need oxygen and give off carbon dioxide everytime they exhale.