NASA Video: Watch US Heat Up by 2100 | LiveScience
The average American emits about 20 metric tons of carbon dioxide into the atmosphere per year, according to climate scientist Michael Mann at Penn State University, who was not involved in the assessment.
"If you condensed all of that gas into solid form and placed it on a scale it would weigh the same as two large male African elephants," Mann told LiveScience. "That's the huge mass of carbon that each of us is, on average, putting into the atmosphere."
For comparison, Mann noted that the average emissions across the entire world are closer to 4 metric tons, which amount to the size of one baby elephant.
"If each of us could reduce our annual emissions to a small baby elephant, we'd go a long way towards making the cuts we need to stabilize carbon dioxide below dangerous levels," Mann said.