Forests in the northern hemisphere could be growing faster now than they were 200 years ago as a result of climate change, according to a study of trees in eastern America.
The trees appear to have accelerated growth rates due to longer growing seasons and higher concentrations of carbon dioxide in the atmosphere. Scientists have documented the changes to the growth of 55 plots of mixed hardwood forest over a period of 22 years, and have concluded that they are probably growing faster now than they have done at any time in the past 225 years – the age of the oldest trees in the study.
Geoffrey Parker, a forest ecologist at the Smithsonian Environmental Research Centre in Edgewater, Maryland, said that the increase in the rate of growth was unexpected and might be matched to the higher temperatures and longer growing seasons documented in the region. The growth may also be influenced by the significant increase in atmospheric carbon dioxide, he said.