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Nature and Environment

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Understanding the Math Behind Global Warming

Air PollutionIt shouldn’t come as too much of a surprise that the weather that’s currently wreaking havoc on the planet tends to amp up the talk about global warming, as well as about what we are doing (or not doing) to battle climate change. Most of the time, global warming can seem too big to tackle, and it brings up a whole slew of discomfort and debate. It’s an amorphous, complicated issue that can’t be solved with a few easy equations.

But Bill McKibben, author, environmentalist, journalist and head of environmental organization, brings equations to the forefront of the climate conversation in a recent Rolling Stone article titled “Global Warming’s Terrifying New Math.” 

He writes, “When we think about global warming at all, the arguments tend to be ideological, theological and economic. But to grasp the seriousness of our predicament, you just need to do a little math. For the past year, an easy and powerful bit of arithmetical analysis first published by financial analysts in the U.K. has been making the rounds of environmental conferences and journals, but it hasn’t yet broken through to the larger public.”

So, larger public, here is McKibben’s rundown of the three numbers to know and what they might mean for our planet’s future.

The first number is 2 degrees Celsius. At the Copenhagen climate conference in 2009, the countries in attendance agreed to the “Copenhagen Accord,” which, according to the article, “ recognized ‘the scientific view that the increase in global temperature should be below two degrees Celsius.’” So far, McKibben says, we’ve raised the average temperature of the planet to nearly half of that allotted increase, to nearly 0.8 degrees Celsius. He calls the agreement upon 2 degrees “the bottomest of bottom lines,” saying that actually raising the global temperature to meet that target could be raising it to a dangerous level.

The second number is 565 Gigatons, which is the amount of carbon that scientists predict humans can release into the atmosphere while still staying below 2 degrees Celsius. And the final number is 2,795 Gigatons, which McKibben says is “the amount of carbon already contained in the proven coal and oil and gas reserves of the fossil-fuel companies, and the countries (think Venezuela or Kuwait) that act like fossil-fuel companies.”

The first number hinges heavily on the second number, and therefore, on the third number (which is five times higher than the second). If 2,795 Gigatons of carbon are actually released into the atmosphere, McKibben says, then it’s game over for the 2-degree target. He goes on to appoint the fossil-fuel industry as the enemy, and says it will be a tough opponent to beat — he calls upon readers to recognize that "...pure self-interest won't spark a transformative challenge to fossil fuel. But moral outrage just might — and that's the real meaning of this new math. It could, plausibly, give rise to a real movement."

McKibben’s focus on numbers and on the new path they should precipitate gained popularity and traction, as well as a variety of responses, after the article was released online. According to a press release, as of one week ago, the article had been shared almost 100,000 times, and viewed online as many as 450,000 times. Calling it a breakthrough moment for a movement, McKibben announced an upcoming series of events that he plans to undertake in early November: “Starting the day after the election, I’d like to go after the fossil fuel industry even more directly, trying — as the Rolling Stone piece suggests — to spark a movement like the ones that overturned the great immoral institutions of the past century, such as Apartheid in South Africa. On November 7th, board member Naomi Klein and I are planning to launch a road show that will cover 20 cities in just over 20 nights (we’re going to break for Thanksgiving) to bring the message I laid out in Rolling Stone to thousands of people across America.”

To read more about the numbers in the article and what they imply, you can check out the full article at For more details on McKibben’s upcoming road show, you can visit You can also respond to the article, or to McKibben’s movement, at

Photo by Fotolia/Taiga 

Amanda Sorell is an Assistant Editor at MOTHER EARTH NEWS magazine. You can find her on .

david mentz
8/21/2012 6:05:28 PM

1970's Lib Mantra: The planet is cooling we're all gonna freeze to death unless we immediately all throw ourselves into socialist bondage!!! 1990's Lib Mantra: The planet is warming we're all gonna drown/fry to death unless we immediately all throw ourselves into socialist bondage!!! Does anyone really need to ask why those who don't tote the partyline and actually think for themselves have SERIOUS reservations about the climate change myth??

michael kelberer
8/14/2012 4:12:01 PM

Nice post, Amanda!

michael kelberer
8/14/2012 4:11:35 PM

"There is absolutely no direct scientific, peer-reviewed evidence of man-made global warming." On the contrary, the ratio of direct scientific peer-reviewed papers supporting man-made global warming to those that don't is in excess of 99-1, according to another peer-reviewed scientific paper.

dan shulla
8/14/2012 3:04:16 AM

Obviously, you're bad at simple math David. The "70s" were 40 years ago, not "20 or so" Were you alive in the 70s? When people stop being greedy and truly listen, you might learn something about the Earth and how it truly works instead of just spouting off like you did.. No direct scientific evidence? Are you a scientist with contradictory evidence that can prove what they say isn't true? Those that understand the seasons can see the changes

john ledoux
8/5/2012 2:26:56 PM

More propaganda from MEN, and any articles from a different side of GW theories.

david mentz
8/3/2012 8:22:28 PM

Just another "the sky if falling" progressive liberal/socialist agenda item that is intended to advance the collectivist cause. There is absolutely no direct scientific, peer-reviewed evidence of man-made global warming. There is however much evidence that leftist global powers wish to seize control of our individual lives and eliminate our personal freedoms in the name of their pet causes like global warming, the entitlement state and faaaaiirrrrness. In the 70's, all you nose in the air liberal progessive lefties were crying about global cooling; makes me wonder did your "scientific" data change that much in the twenty or so years that precipitated a switch in your position from global cooling to global warming, or did your polling/focus groups simply reveal that warming pulled stronger at people's hearts than cooling did?