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This story is part of Streetsblog Denver’s
partnership with Covering Climate Now, a global
collaboration of more than 300 news outlets to
strengthen coverage of the climate story.

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Greenhouse gas emissions are often discussed in terms of their weight in tons. But if I told you the EPA estimates that an average car releases 4.6 metric tons of carbon dioxide per year, you might have a tough time picturing all of that gas hanging out in the sky.

One way to think about it is to imagine the amount of space one ton of carbon dioxide takes up in the atmosphere. Picture a cube measuring 27 feet on each side according to the United Nations. That’s roughly three stories high. 

In 2009, artists created the first “climate cube,” a life-size sculpture displayed at the UN Climate Change Conference in Copenhagen (video). The European Space Agency displayed another in Paris in 2015. 

Once you can imagine a climate cube, know that if you’re an average person in a developed country, you generate about one per month. Home energy, garbage, food and transportation add up to about one ton of heat-trapping emissions per month. 

In the United States, cars, trucks and other vehicles are the largest source of greenhouse gas emissions, making up 29 percent of the country’s carbon dioxide output, according to the EPA. 

Knowing that the average car belches 4.6 cubes per year, now imagine how the emissions of all the cars on Colorado’s Front Range add up. 

They will release an estimated 14.7 million tons of carbon dioxide next year, according to projections from the Denver Regional Council of Governments. If each ton formed a 27-foot cube and they were stacked end to end, they would extend 75,389 miles, which could circle the planet three times. 

Unfortunately, electric vehicles are not likely to cut Colorado emissions by much over the next 20 years. Though the state adopted a zero-emissions vehicle standard last month, it requires just 6.3 percent of each automakers’ sales to be ZEVs by 2030. 

With nearly all cars likely to continue burning fossil fuels, Front Range vehicle emissions are estimated to decline only 8.8 percent between 2020 and 2040, according to the 2018 Greenhouse Gas Emissions estimate from the Denver Regional Council of Governments.  

Beyond Colorado, the world produced an estimated 37.1 billion metric tons of greenhouse gas emissions in 2018, according to a report covered in Scientific American. If we imagine end-to-end climate cubes, they would stretch 189.7 million miles, which would circle Earth 7,619 times.

Since 1751, Humans have pumped somewhat more than 400 billion metric tons of carbon dioxide into the atmosphere, according to the Carbon Dioxide Information Center. That translates to just over 2 billion miles of climate cubes, which would wrap the planet 82,142 times.