Now nine months after his arrest outside the White House, climatologist James Hansen is in the news again, and this time he is offering a personal response to Obamaâ€™s environmental policies. In particular, he singled out Obamaâ€™s acceptance of Canadaâ€™s oil sands and why exploitation of the oil sands is so detrimental to the environment.
According to Hansen: â€œCanadaâ€™s tar sands contain twice the amount of carbon dioxide emitted by global oil use in our entire history.â€
The consequences of such high CO2 concentrations are by now well known. Not only would the global temperature rise a few degrees, it would cause food prices to skyrocket, sea-levels to rise, and 20 â€“ 50 percent of the Earthâ€™s species to go extinct.
If we continue to exploit the oil sands, CO2 concentrations could outstrip the levels seen during the Pliocene era 2.5 million years ago, where sea levels were 50 metres higher than they are today.
Although many of these consequences seem several decades down the road, we are already beginning to feel some of the effects of climate change now. For instance, we can say with â€œhigh confidenceâ€ that the heat waves in Moscow and Texas were caused by climate change. Extreme weather events like these will become more prevalent in the future, early warning signs that the Earthâ€™s natural systems are reaching tipping points.
Unfortunately, the longer we wait to impose effective climate policies the more expensive it will get.
What are your thoughts on Canadaâ€™s oil sands? Do you think the environmental impacts associated with the oil sands are as severe as Hansen suggests?
Image by NASA:Â Mining operations in the Athabasca oil sands