New research links pine tree smell to climate change progress

New research suggests a strong link between the powerful smell of pine trees and climate change. Scientists say they have found a mechanism by which these scented vapors turn into aerosols above boreal forests.

These particles promote cooling by reflecting sunlight back into space and helping clouds to form. The research, published in the journal Nature, fills in a major gap in our understanding, researchers say.

One of the biggest holes in scientific knowledge about climate change relates to the scale of the impact of atmospheric aerosols on temperatures. These particles form clouds that block sunlight as well as reflecting rays back into space. They can be formed in a number of ways, including volcanic activity and by humans, through the burning of coal and oil.

According to the Intergovernmental Panel on Climate Change (IPCC), they "continue to contribute the largest uncertainty to estimates and interpretations of the Earth's changing energy budget."

One of the most significant but least understood sources of aerosols are the sweet-smelling vapors found in pine forests in North America, northern Europe and Russia. These aerosols have confounded climate models, as scientists have not been able to predict how many of the particles form.

The authors believe that this is playing a significant role in reducing the impact of rising temperatures. They argue that this effect is likely to strengthen in the future. The scientists stress that the new understanding is not a panacea for climate change, as forests will stop emitting vapors if they become too stressed from heat or lack of water.

AJP