Nature - Absorption Of CO2 By Plants Will Decrease As Planet Warms; Soil CO2 Output Will Rise
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But in a study published Wednesday in the journal Nature, researchers found that under a warming climate, rather than absorbing more greenhouse gas emissions, plants and soil may start absorbing less, accelerating the rate of change.
We have this image of the planet getting very, very green as we move into the future, said Pierre Gentine, a professor in the Department of Earth and Environmental Engineering at Columbia University and an author of the study. But it may be the opposite. It is well known among climate researchers that atmospheric concentrations of carbon dioxide increase during dry years, a sign that the earth is absorbing fewer emissions.
When the soil is dry, plants are stressed and cant absorb as much CO₂ to perform photosynthesis. At the same time, because dry conditions are often accompanied by warm temperatures, microorganisms in the soil, which are more productive when its warm, release more CO₂.
As the climate changes, scientists know that there will be more years of extreme weather. That means extreme droughts, followed by years of heavier than normal rainfall, will become more likely. Dr. Gentine and his colleagues wondered if those conditions would balance out.
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https://www.nytimes.com/2019/01/23/climate/plants-co2-climate-change.html?rref=collection%2Fsectioncollection%2Fclimate&action=click&contentCollection=climate®ion=rank&module=package&version=highlights&contentPlacement=2&pgtype=sectionfront