Global Climate Change: Our CO2 Contributions

When scientists and the media tell us about Global Warming, for the most part it flies completely over our heads, our eyes glaze over and we flip the channel to try to see if Family Guy is on. When you have people talking to you about the difference between X many parts per million of CO2 in the atmosphere and how a 2 percent rise in global temperatures will sink Miami into the ocean, you’re giving out numbers and concepts that have very little basis in our collective reasoning to understand what exactly it all means. What in the hell are they talking about? There’s a disconnect in our brains between cause and effect, especially on a planetary scale. Funny enough though, if you take the time to research and go through the numbers it becomes a bit more clear.

Ok seriously, this might be a little boring, but if you stick with me for a few minutes and follow me through, hopefully you’ll get an idea that overcoming global warming and getting us off of our dependance on fossil fuels isn’t such a hopelessly herculean task as we may think.

We’ve all heard the warnings of our warming planet, melting glaciers and rising sea levels. To put this into perspective and to give it a number and a probability of happening scientists all over the place have been debating how many tons of carbon needs to be released into the atmosphere in order for there to be a greater than 50% chance of the average temperature rising above 2 degrees. Remember we’re talking risk management here, so that 50% number is really important. What does that mean and why should we care about that 2 degree rise? Above 2 degrees and the Greenland icesheet melts and the oceans rise by about 7 meters... New York, Gone, most of East coast coastal towns and cities, gone, Louisiana, Gone...

Two very smart people who have been at the forefront of global warming research for quite some time and have the street-cred to claim title to “expert” have differing opinions as to how much CO2 needs to be released into the atmosphere before we hit that 50% threshold. Allen Myles is the head of climatology at Oxford and has worked for the UN and MIT - he’s smarter than most of us and believes that 480 billion tons puts us over the 50% marker. Malte Meinshausen (Potsdam) is a little less optimistic and says that 310 Billion puts us over the probability point.

Depending which sources you believe the average American emits 20 tons of CO2 annually (Source: Carbon Dioxide Information Analysis Center - CDIAC).

Our per person emissions are about 12.5 tons (Source: EIA). The average American drives between 12,000 and 15,000 miles a year, with an average miles per gallon of 25 and CO2 emissions from a gallon of gas equal about 20 lbs (Source: EPA), then we emit about 10,800 lbs of CO2 from our cars annually. So per person and then throwing in a car, the number roughly matches the 20 tons number from the CDIAC...

US population is at about 300 million, multiply that by 20 tons of CO2, we emit about 6 billion tons annually or 20% of global emissions. So with 30 billion tons of global CO2 emissions, we’ve got about 10 or 15 years to start moving things in the opposite direction - or at least significantly slow them down to prevent tipping over that 50% threshold.

Needless to say this is an oversimplified version of our relative contributions. The point is to show how climatologists are getting to their numbers, broken down into our own individual contributions so that those numbers are a little bit more accessible mentally to us – when we talk in the billions of tons, I think there is a communal yawn that can be heard throughout the audience – 20 tons, okay, that’s a number I can comprehend, especially now that you’ve told me half of that comes from me tooling around in my car…