A new study conducted by the Lawrence Berkeley National Laboratory (LBNL) has found that the anti-greenhouse effect of CO2 has been underestimated. The study shows that a higher concentration of carbon dioxide in the air increases the growth of plants, which in turn binds the greenhouse gas and removes it from the atmosphere. The research team has determined the size of the effect and how it affects the rise in humidity and temperatures. The study, published in the journal PNAS, suggests that the CO2 content in the air could promote global plant growth more than previously thought, which would increase the absorption of the greenhouse gas by plants.
The scientists used measurements of gas exchange at the Earth’s surface to determine the extent of the CO2 fertilization effect on photosynthesis. They found that an increased photosynthesis activity would lead to plants binding an average of 9.1 grams of carbon per square meter annually. About half of this is due to the increased CO2 concentration in the atmosphere. The study also found that higher air temperatures have a significant impact on the growth of plants. However, the specific humidity and soil moisture content have a relatively small effect on photosynthesis, but are crucial for the high variability of the measurements.
The researchers compared their data with simulations from 13 global vegetation models and eight satellite images to verify their findings. They suggest that an expanded measurement network is needed to obtain more accurate data, particularly in the tropics where there are currently only a few measurement stations. While the study has been praised for its methodology, some experts have pointed out that the statistical values may be limited due to the relatively short 14-year study period. Additionally, the study does not address what happens to the CO2 in the biosphere, as it could be stored or released back into the environment.
Overall, the study highlights the importance of understanding the role of plants in mitigating the effects of climate change. The findings suggest that the anti-greenhouse effect of CO2 is more significant than previously thought, and that plants could play a crucial role in reducing the amount of greenhouse gases in the atmosphere.
