Climate 'Time Machine' Tests Future CO2 Levels

A climate time machine has been erected in Australia. The contraption, comprised of several nine-story-tall frames with pipes that pump carbon dioxide into the air surrounding a forest, is part of an experiment to measure the effect of carbon dioxide on real woodlands -- and get a glimpse of the future.

The four-acre project, called Eucalyptus Free Air Carbon Enrichment (EucFACE), is an experiment run by the University of Western Sydney. Scientists have embarked on it because although carbon dioxide levels planetwide have risen in the past century, it's unclear how much of the CO2 plants can absorb and what will happen as those concentrations rise.

Current CO2 levels are about 390 ppm; pre-industrial levels of CO2 were about 280 parts per million. Doubling the amount of CO2 in the air generally raises average global temperatures by about 3 degrees Celsius (5.4 degrees Fahrenheit). Additionally, recent studies have hinted that the climate may be more sensitive to CO2 levels than anyone thought, so getting a good picture of the effects might be urgent.

Over the course of several months, the researchers will increase the amount of CO2 from 390 ppm to 550 ppm, the level predicted for later this century. They will then study the trees for the next 10 years to see how (and whether) they adapt to the new CO2 concentrations.

The height of the frames allows instruments to measure what happens at different levels of the forest –- from the canopy to the forest floor.

The study is particularly important for Australia, since the kind of woodland being studied covers a lot of the country and is an important part of Australia's local carbon strategy -- if the amount that the trees take up drops, for instance, then reducing carbon emissions might mean planting different kinds of trees or implementing tougher emissions standards.

By the end of the ten-year experiment, the scientists should have a better idea of what's in store for Australian forests (and by extension, others as well). And with any luck it might offer insights about what to do if they're adversely affected.

This story was provided by Discovery News.