The earth tilts on its axis twenty-three degrees. In the Northern Hemisphere’s summer, the Arctic ice cap leans into the sun. It performs a systemic function, reflecting the sun’s radiation back into space to keep the planet in the narrow temperate zone that sustains the plants and animals that have evolved on it over the eons. Once the ice cap is gone, that radiation will be absorbed by the dark Arctic waters.
The Arctic ice underlies the temperature gradient responsible for the jet stream and the seasonal highs and lows that govern the rains in northern latitudes. When the ice is displaced by warming seas, and the gradient decreases, the highs and lows will not form as they once did but will shift, or form earlier or later, or grow larger or smaller, or direct the jet stream differently, or do all of these things. The rains will fall where they shouldn’t, when they shouldn’t, in amounts they shouldn’t, instead of where, when, and in the amounts that the seven billion souls on this planet depend on to grow grains and fruits and vegetables.
And each year, it will get worse. Once the ice cap goes, even if just for a few weeks, a self-reinforcing feedback loop will have been set into irreversible motion. The permafrost at the edge of the Arctic will melt and release eons of sequestered methane and carbon dioxide, which will drive yet further warming, and further melting, and further releases. Seasonal weather patterns will be further distorted. From the point of view of agriculture, the atmosphere will experience total systemic failure.
The graph below tracks the extent of the Arctic sea ice over the past decades. The dark gray line is the statistically “expected” or “mean” value based on empirical data from 1989 to 2010. The light gray area represents two standard deviations from the expected value, based on the variability of the empirical data. By definition, two standard deviations cover about 95% of the expected outcomes.
As the colored lines show, all of the outcomes since 2007 have fallen near or below the lower gray band. This means that events that should happen 2.5% of the time (half of 5%) are happening virtually 100% of the time. And that’s after the band has been adjusted from the 1979-2000 timeframe, which was significantly higher on the y-axis. The bar has literally been lowered.
The shrinking is confirmed by this second graph, which shows the trend of areal ice loss.
Next, and perhaps the most worrisome for being the least broadly recognized, is the trend in volume. Not only is Arctic ice shrinking in area, but it’s thinning—just like ice on a pond in spring. Here’s a graph from the Polar Science Center at the University of Washington’s Applied Physics Laboratory. Again, note the gray bands which represent two standard deviations from the expected, and how recent values persist below the 2.5% probability level.
Finally, here’s a graphic of the record-low Arctic sea ice extent in September 2012. To see more, go to the NSIDC’s website.
The Arctic ice cap is the idiot light at the top of the world.
So—throw up our hands? That’s one reaction. The other is to get serious and cut carbon emission as much and as soon as possible.
How do we do that? First, we have to believe the situation is real and imminent. Second, we have to believe we can make the changes that need to be made. Third is a World War Two-style effort to enact these two beliefs. Fourth, we need a carbon tax to fund that effort, which could be financed in part by a reduction in income taxes.
There’s nothing wrong with cap-and-trade conceptually; it’ll just take too long. We need need a carbon tax as soon as possible to fund the big, systemic efforts that are going to make the real difference. The time for incremental solutions has passed.
Fifth, to do the big, systemic things, we have to have leaders determined to do it.
The only way any of this happens is if we believe human-caused climate change is real and elect leaders who think the same.