Climate Change

350: The Number that could Shape Our Destiny

By Ryan McGreal
Published May 28, 2008

Bill McKibben has written an utterly arresting op-ed for the LA Times in which he argues from scientific evidence that humanity is budging up against its last chance to get atmospheric CO2 below 350 parts per million (ppm) before a number of climate tipping points take out our capacity to stop the greenhouse effect.

A few weeks ago, NASA's chief climatologist, James Hansen, submitted a paper to Science magazine with several coauthors. The abstract attached to it argued - and I have never read stronger language in a scientific paper - that "if humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm."

McKibbon returns to the key phrase, "if humanity wishes to preserve a planet similar to that on which civilization developed" in a desperate plea to pull ourselves back before it's too late.

One tipping point is the arctic ice cap, which reflects 80 percent of solar energy back into space. Once it melts, the sea will absorb 80 percent of solar energy.

Another tipping point is the arctic tundra in which vast amounts of methane gas are sequestered in the permafrost. Once that permafrost thaws, the methane will pour into the atmosphere and intensify the greenhouse effect.

Yet another is changing rainfall patterns and migration of insects to new regions, which threatens the carbon sequestered in millions of acres of forest.

[W]e have, at best, a few years to short-circuit them -- to reverse course. Here's the Indian scientist and economist Rajendra Pachauri, who accepted the Nobel Prize on behalf of the Intergovernmental Panel on Climate Change last year (and, by the way, got his job when the Bush administration, at the behest of Exxon Mobil, forced out his predecessor): "If there's no action before 2012, that's too late. What we do in the next two to three years will determine our future. This is the defining moment."

Not only are we not taking action, but we're actually accelerating our greenhouse gas production. While politicians at all levels stall and balk over banal procedural issues, we continue to approach the drop-dead date, that point at which it no longer matters whether we try to stop feeding the cycle.

Is there any way to pull ourselves back from the brink in time?

Ryan McGreal, the editor of Raise the Hammer, lives in Hamilton with his family and works as a programmer, writer and consultant. Ryan volunteers with Hamilton Light Rail, a citizen group dedicated to bringing light rail transit to Hamilton. Ryan wrote a city affairs column in Hamilton Magazine, and several of his articles have been published in the Hamilton Spectator. His articles have also been published in The Walrus, HuffPost and Behind the Numbers. He maintains a personal website, has been known to share passing thoughts on Twitter and Facebook, and posts the occasional cat photo on Instagram.

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By dobermanmacleod (anonymous) | Posted May 29, 2008 at 05:22:53

Do I need to point out that the CO2(e) [i.e. all the greenhouse gas in the air expressed in terms of CO2 equivilent] is already above 450ppm? Furthermore, most reasonable people know that it is doubtful that it is possible to keep the CO2 level below 450ppm, and quite possibly 550ppm.

know of no realistic person who thinks carbon dioxide emissions are going to do anything but grow. Most European countries are not meeting their emissions goals, and of the ones that have, it's because their economies are collapsing. In the United States, this notion that we're going to reduce our emissions by 80 percent is pure fantasy. --Pete Geddes, Foundation for Research on Economics and the Environment, 2 April 2008

"I'm going to tell you something I probably shouldn't: we may not be able to stop global warming. We need to begin curbing global greenhouse emissions right now, but more than a decade after the signing of the Kyoto Protocol, the world has utterly failed to do so. Unless the geopolitics of global warming change soon, the Hail Mary pass of geoengineering might become our best shot." --Bryan Walsh, Time Magazine, 17 March 2008

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By gullchasedship (registered) - website | Posted May 29, 2008 at 11:51:58

I wonder what happened 900 years ago when the Medieval warming period started. People could farm on Greenland and grow wine grapes in northern Britain. It seems like we survived that "crisis".

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By peter (anonymous) | Posted May 30, 2008 at 23:18:32

the medieval warm period was 'warm' relative only to typical temps of that period - northern europe's temperatures were actually the same as today, perhaps cooler. also, grapes were not being grown in northern britain but in southern britain, just as they are today.

really, it's just a lame way for global warming conspiracy theorists to attempt to find flaw in what is patently obvious - our climate is changing, dude!

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By Undustrial (registered) - website | Posted June 01, 2008 at 12:03:21

I'm tired of hearing that reducing our greenhouse gas emissions is unrealistic. Canadians and Americans burn more energy than anybody anywhere, and more than anybody ever has. The notion that we can't find a way to curtail that is laughable. For most of humanity, luxuries like automobiles, air conditioning, clothes dryers and the like are nothing but pipe dreams.

We could easily do without them, we simply choose not to. We are some of the richest, most technologically advanced and educated people who have ever lived, and yet we constantly approach this crisis (and others, like oil depletion, mass extinctions and loss of farmland) with the characteristic forethought of drunks, smokers or junkies. "I know it's killing me, but what do you expect me to do, quit?"

We could cut our emissions drastically and relatively quickly with some fairly simple changes, many of which have been elaborated at length many times on this site. Rational land use decisions, organic farming and vegetarianism, sensible home design (insulation, passive solar, etc), and a general re-naturalization of our landscapes (sorry, but wildflower medians simply sequester more carbon than machine-manicured grass), are all it would take.

A clothes line represents next to no energy in manufacture, about $5 to buy, and requires no long-term energy or financial inputs to operate. Similar low-cost, low-tech solutions are available everywhere, from bikes to backyard gardens to mended clothing and shorter showers, and are practiced extensively by some of the most vulnerable and marginalized people around, be it North Hamilton or South America. It's not a question of cost or technology, it's a question of will.

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By David (anonymous) | Posted June 18, 2008 at 08:15:38

The problem is finding the country that wants to be the first to shut down their power plants, cars, and economies in order to make a meaningful difference.

But perhaps Peak Oil will make the problem self-limiting, with involuntary economic shutdowns and half the world starved to death.

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