carbon bathtub climate change model

Paris Climate Talks: the Importance of Visualizing Climate Change


Four days into the Paris Climate Talks, other news has already pushed this earth shaking topic below the fold on the NYTimes front page and off the top of the NPR hourly talk items.  We understand.  Climate change is not fun, and it’s not sexy.  But it is UTTERLY IMPORTANT.  Maybe some simple, effective graphics can help with visualizing climate change and help us keep the important facts in mind.

The Importance of Visualizing Climate Data

Climate change is a huge and complex issue, filled with abstruse science and murky politics.  It’s hard to understand, even for well educated people, as was proved by John Sterman, of the MIT Sloan School of Management.  He was puzzled by the lack of public concern over climate change.  In 2008, he came up with a study which gave a short summary of information on climate change to a group of MIT graduate students and then quizzed them about the effects on the environment of certain human behaviors.

He found that 63% of them misunderstood the situation – they believed that if we simply stopped increasing our carbon emissions, global temperatures would stabilize even though we are currently adding more carbon to the atmosphere every year than there is capacity to absorb.  Read his paper on the subject here

To counteract this complacency he developed the Bathtub model – a simple way of visualizing climate change as a soon-to-be-overflowing tub.  National Geographic has created a detailed image of the same idea here.  Our sketch (above) shows the most simple version of the concept – if you put more water into a tub than can flow out … you’ll end up with water on your floor!

Putting Words into Images

One of the most compelling things I’ve read about the current situation is Justin Gillis’ “Paris Climate Talks Avoid Scientists’ Idea of ‘Carbon Budget.” This article for the NYTimes points out that the agreements that national leaders are making in Paris WILL NOT ACCOMPLISH THE GOALS THEY HAVE ALREADY AGREED TO.  The article makes a great verbal point about how doing less bad things doesn’t equal positive change (which we have illustrated below):

climate diet

“In effect, the countries are vowing to make changes that collectively still fall far short of the necessary goal, much like a patient who, upon hearing from his doctor that he must lose 50 pounds to avoid life-threatening health risks, takes pride in cutting out fries but not cake and ice cream.”

While it is very hopeful that our International governments are coming to the table to discus this issue, and propose real improvements, this event already has a big flaw.  The idea of a Carbon budget isn’t even on the table.  Anyone who has ever achieved a goal on time understands the value of noting the deadline and then dividing up tasks to fit into it.  Likewise, any project with completed for the goal cost probably has a strict budget to follow.

The world already agreed in 2010, at the Cancun talks, that we should keep the warming of the planet below 3.6 degrees Fahrenheit, and scientists have a fair understanding of the amount of Carbon emissions that will meet or exceed that goal.  But we aren’t talking about that number or how to stay below it.  Again from Gillis’ article:

climate pie

“… About two-thirds of the pie has already been eaten by a handful of rich countries, plus China. At current rates, the remainder of it will be gone in 30 years or less. Many poor countries are crowding around the table, pleading for a sliver, but the big emitting countries insist on laying claim to most of the rest of the pie.”

Here’s one more powerful visual analogy.  It is Thanksgiving for the world, and we have already eaten 2/3 of the pie on the table.  How are we going to divide up the rest of it fairly?