Conflicting Reports

The rising rates of man-made Carbon Dioxide being released into the environment is at the core of the debate whether humans are contributing to climate change. In other words, some argue that as we produce more CO2, the temperature will continue to rise because of this. The following two articles discuss the CO2 Fertilization Effect. They were published within a few days of each other.

As Carbon Dioxide Grows, Tropical Trees Do Not


By Elizabeth Harball, ClimateWire on December 16, 2014

Trees are definitely our allies when it comes to taking in greenhouse gases and thus aiding in the fight against climate change. But new research suggests that forests might not be quite as helpful as we’d hoped.

Computer models that predict how climate change will play out assume that as greenhouse gas concentrations go up, forests will take advantage of the additional carbon dioxide and grow a bit more, increasing their capacity to mitigate global warming.

NASA Finds Good News on Forests and Carbon Dioxide

Written by Carol Rasmussen Dec. 29, 2014

A new NASA-led study shows that tropical forests may be absorbing far more carbon dioxide than many scientists thought, in response to rising atmospheric levels of the greenhouse gas. The study estimates that tropical forests absorb 1.4 billion metric tons of carbon dioxide out of a total global absorption of 2.5 billion — more than is absorbed by forests in Canada, Siberia and other northern regions, called boreal forests.

“This is good news, because uptake in boreal forests is already slowing, while tropical forests may continue to take up carbon for many years,” said David Schimel of NASA’s Jet Propulsion Laboratory, Pasadena, California. Schimel is lead author of a paper on the new research, appearing online today in the Proceedings of National Academy of Sciences.

Forests and other land vegetation currently remove up to 30 percent of human carbon dioxide emissions from the atmosphere during photosynthesis. If the rate of absorption were to slow down, the rate of global warming would speed up in return.


Carbon Dioxide Fertilization

The CO2 fertilization effect or carbon fertilization effect suggests that the increase of carbon dioxide in the atmosphere increases the rate of photosynthesis in plants. The effect varies by species and availability of water.[1]

From a quarter to half of Earth’s vegetated lands has shown significant greening over the last 35 years largely due to rising levels of atmospheric carbon dioxide.