Would Keystone pipeline unload "carbon bomb" or job boom?

If the pipeline is approved and the fuse lit, climate scientist James Hansen says it's: "Game over for climate."

Environmental opponents don't mince words on the Keystone XL pipeline. Some call it the "fuse to the biggest carbon bomb on the planet" because of the carbon emissions from the oil it will carry.

Backers say the Canada-to-U.S. pipeline could lower U.S. dependence on unstable foreign sources of oil and create thousands of jobs. Yes, it could create jobs — but not as many as some claim. The State Department estimates that during construction, the project would create 3,900 one-year construction jobs and 38,200 indirect ones, but during operation, only about 50 jobs. Keystone's owner, Calgary-based TransCanada, says the pipeline would generate about 9,000 construction jobs. But hardly any permanent jobs in the U.S.

The State Department's review says the 1,179-mile pipeline, which would carry heavy oil sands from Hardisty, Alberta, through Montana and South Dakota to Steele City, Neb., would do little to change U.S. gasoline prices or oil imports. The reason: Oil is traded on a global market that adjusts to shifts in supply and demand. So even if North America produces more oil, that doesn't mean it stays here.

"The tar sands are about the dirtiest and most carbon-intensive of the fossil fuels, especially when you consider the damage done and energy used in getting them out of the ground," Hansen writes in an e-mail. He says they contain twice the amount of oil burned in human history and if developed, "it is game over — we will not be able to stabilize climate." 
 
MORE> USA TODAY March 1, 2014