Cloudy, polluted skies may be just what the botanist ordered. A new discovery was made last week regarding the positive effect various atmospheric pollutants may have on global plant life. This study was published in Nature through the combined efforts of the Centre for Ecology & Hydrology, the Met Office Hadley Centre, ETH Zurich and the University of Exeter. They found that, though microscopic pollutants like aerosol particles cause a phenomenon referred to as “global dimming” – a gradual process in which the amount of sunlight reaching the earth’s atmosphere diminishes greatly – they are actually contributing to increased carbon absorption by earth’s vegetation.

Though the amount of direct sunlight directly on the top of plants decreases, the atmospheric particles cause the light from the sun to scatter and hit the plants leaves from many different angles. This “diffuse radiation” subsequently causes plants to have a net increase in sunlight exposure, increasing the rate of photosynthesis and resulting in greater carbon absorption.

According to Dr. Lina Mercado of the Centre for Ecology and Hydrology, “the effects of atmospheric pollution seem to have enhanced global plant productivity by as much as a quarter from 1960 to 1999.” This, she says, has accounted for a 10% net increase in the amount of carbon emissions stored on land.

These new data has caused the scientific community to reconsider the effects of reducing atmospheric pollutions at a rapid pace. It is generally acknowledged that the amount of airborne pollutants humans release should be reduced for the benefit of public health as well as to stem environmental effects that pollutants have on wildlife in general.

However, with this recent study, it is becoming apparent that with every step closer to having clear skies, we take a metaphorical “two steps backward” in the fight to reduce humanity’s carbon footprint.

Discussion Question:
How might this catch-22 of atmospheric emissions change the face of “going green”?

News Story:
http://news.biocompare.com/News/NewsStory/271406/Plants-Absorb-More-Carbon-Under-Hazy-Skies.html

Science Article:http://www.nature.com/nature/journal/v458/n7241/abs/nature07949.html