A new paper in Science by Dirk Notz and Julienne Stroeve suggests a direct relationship between the yearly September extent of Arctic sea ice and carbon dioxide emissions. It’s amazingly simple: every metric ton of carbon dioxide we add to the atmosphere means 3 fewer square meters of sea ice at the end of the summer.
Here’s the key quote and figure from the paper:
We here use a robust linear relationship between monthly-mean September sea-ice area and cumulative CO2 emissions to infer the future evolution of Arctic summer sea ice directly from the observational record. The observed linear relationship implies a sustained loss of 3 ± 0.3 m² of September sea-ice area per metric ton of CO2 emission.
In the United States, carbon dioxide emissions per capita in 2014 was 16.5 metric tons. So the math continues to be simple. The average American causes about (16.5 t) × (3 m²/t) = 49.5 m² of sea ice to melt each year. That’s 533 square feet, or about the area of a quarter of a tennis court. A family of four melts a full tennis court. A typical neighborhood melts the area of an entire football stadium.
Another example: According to carbonfootprint.com, a round trip flight from New York to London is worth about 0.8 metric tons of CO2 per passenger, or 2.4 square meters of lost Arctic sea ice, or about half a ping pong table.
The ominous part of the paper is that at this rate, the Arctic will see ice-free summers within about three decades. The consequences for our climate could be catastrophic.