More Global Warming Upside
From today's issue of the Telegraph, more good news for the CHL. Yes, we are even able to recruit trees as volunteers!

Heatwave Britain - when the trees turn toxic
by Richard Alleyne and Ben Fenton

The green lungs of the countryside, fondly imagined to be our greatest defence against air pollution, could actually be having the reverse effect, scientists said yesterday. Researchers claim to have discovered that the commonly held view that trees and plants act as filters, purifying the air and reducing harmful gases, is turned on its head during times of extreme heat. According to a team from York University, when temperatures top 95F (35C), our native plants and trees start emitting "cooling" chemicals such as isoprene and turpene into the atmosphere which in turn encourage the production of ozone. The toxic gas, which is particularly dangerous for children, the elderly and asthmatics, was responsible for as many as 600 deaths during last summer's record-breaking hot spell, it is believed.

And with heatwaves like last summer's - when temperatures reached 100F (37.7C) - expected to become more regular due to global warming, the phenomenon could reverse Britain's recent improvements in air quality. "Current predictions suggest that the heatwaves could happen 10 times more often," said Prof Alan Thorpe of the Natural Environment Research Council's Centres of Atmospheric Science, which funded the research. "Along with all our other problems, we are going to have to deal with severe ozone pollution." The new source of atmospheric pollution could mean thousands of Britons having to wear charcoal masks and stay indoors during heatwaves to avoid the clouds of ozone.

The team discovered the new source of pollution when it studied ozone levels in Chelmsford, Essex, during August last year. "By chance, we picked the two weeks of the heatwave. What we discovered was startling," said Alastair Lewis, who led the research. "When the temperature reached the high 90s and topped 100, plants and trees, which normally give off relatively small amounts of isoprene, started to produce greatly increased amounts."

It is thought that isoprene, which is released by deciduous trees, and turpene, which is emitted by evergreen trees, help protect leaves from heat and sun damage. In the atmosphere isoprene and turpene act as catalysts, increasing the rate at which sunlight breaks down nitrogen oxide - a car pollutant - into ozone. The more isoprene and turpene there is, the more ozone is produced from smaller amounts of nitrogen oxide.
- nostradamusfunkadelic, 1:41 PM | |