November 10, 2010

Climate change facts are hard to pin down

As published in The Erin Advocate

Just after writing about the benefits of tree planting in the effort to ease the impacts of climate change, I read about a study from the University of Guelph suggesting that tree planting is not going to be as much help as expected.

Understanding climate change science these days is like trying to nail Jello to a wall – there are just too many people with an interest in keeping it slippery.

Researchers went to 2,300 sites on six continents to study the yearly growth rings on 86 types of trees. Higher carbon levels in recent decades have been thought to boost tree growth, which would capture more carbon and slow the rate of global warming. It appears that in 80 per cent of the world's trees, it is not happening.

"We can’t look to forests to offset emissions from burning fossil fuels,” said co-author Ze’ev Gedalof, Associate Professor of Geography at Guelph. “There might be a very slight increase in the total rate of growth in trees, but they’re not going to be these vacuum cleaners that will magically suck up the CO2 that we’re emitting.”

As often happens, some scientists say the results are inconclusive and oversimplified. And as usual, there's a strong political message: Don't be complacent about climate change, just because we're planting lots of trees – we still need to reduce the carbon footprint created by our factories, vehicles and lifestyles.

Trees have many benefits for water, wildlife and the human environment, even if the carbon sink turns out to be smaller than expected. Our tax dollars support a lot of tree planting by Credit Valley Conservation and Wellington County – one million trees have been planted since 2004 under Wellington's Green Legacy Program, making it the largest municipal tree planting program in North America.

Forest now covers about 17 per cent of Wellington, but Environment Canada says 30 per cent is needed to maintain a healthy water system. Another 50 million trees are needed, so Rob Johnson, Green Legacy Tree Nursery Manager, is not content with the current rate of 156,000 trees a year. “If each resident planted just ten trees, almost one million trees would go into Wellington County annually,” he said.

When it comes to public policy on climate change, there's a huge public relations battle going on. Scientists appear truly baffled that people do not take their warnings seriously. The public is glad to enjoy the benefits of new technology, but is suspicious of scientists – perhaps seeing them as manipulative, or too idealistic.

The conflict swirls on many fronts, including the "Degrees of Change" chart and analysis published by Canada's National Round Table on the Environment and the Economy, and the Royal Canadian Geographical Society. It outlines various impacts of climate change, but says they won't be too bad, and that there will be benefits.

I am not knowledgeable enough to say they are wrong, but I do not trust the study's main sponsor, Suncor Energy (Petro-Canada/Sunoco), a major oil sands and greenhouse gas producer. The chart has become a target.

“It is full of bad science and utterly downplays the serious impacts of climate change” said U of T climate scientist Danny Harvey, quoted on “How can we (Canada) talk about profiting from climate change when most of the world will suffer devastating impacts, in part because of our emissions? It is disgusting.”

I also do not trust the Canadian government, which has dedicated itself to doing as little as possible on climate change. It has banned its own scientists from speaking freely to the media, even about climate change research that they have already published. The federal scientists' union says they face "dwindling resources and confusing policy decisions," and they've started a website,, to make their work better known.

Virtually all climate change scientists agree that human industry is making things worse, yet there was not enough support in the US Congress to legislate emissions reductions – even before the recent elections that brought more climate change deniers into power. Stephen Harper can relax now – there is no longer any chance of the US slapping restrictions on Canadian oil sands.

California has a greenhouse gas reduction law. Two oil companies spent $10.5 million supporting a proposition to suspend that law until unemployment declines to 5.5 per cent for 12 months. Voters rejected the proposition, perhaps moved along by the $31 million spent by environmental groups and other businesses to defend the law.

So the expensive fighting carries on, with the environmental movement winning the occasional battle, but remaining a long way from winning the war.