Yesterday I had the opportunity to share a few ideas about the future of transportation, and the future in which transportation will take place, to the 2013 Texas Transportation Forum. I will share the whole presentation in a bit, but one of the slides I used had the classic Arctic ice map from the National Snow and Ice Data Center. It was the map from September 16, 2012 when the ice reached its lowest level recorded since measurements have been made, after the summer melt.
The point I was making was that the loss of Arctic ice is hypothesized to be related to unusual behavior in the jet stream, namely leading it to dip further south, and to get stuck in fixed positions for longer periods of time. This then contributes to longer heat and cold waves, longer droughts and rain storms, and so on. Thus, I suggested not terribly originally that future transportation systems must be planned to be more resilient, and of course I implied that they ought to be less carbon intensive.
What I did not note is a fact that I’ve been aware of but came across again today, that it is not just the area of ice that is declining through the years of observation, but even more dramatically, the volume of ice. That is, each summer the ice melts and in most summers more of the ice melts than previously. Each winter the ice re-freezes. But at the end of the freezing season, the ice is not as thick as previously, and thus is easier to melt in the next melt season. It is only recently that we’ve been able to monitor ice thickness and volume using the ESA CryoSat 2 space craft which uses “a high-resolution synthetic aperture radar altimeter, which fires pulses of microwave energy down towards the ice” and thus enable measurements of ice thickness.
The findings are pretty startling. A recent report summarized at the University of Washington concludes that “the summer minimum in Arctic sea ice is one-fifth of what it was in 1980…” The area of ice has fallen by half, but the total volume even more.
The Arctic is a canary in the coal mine. There is great uncertainty about what an ice free late summer in the Arctic will mean. Release of methane? Harsher storms? We apparently are going to find out in the coming decades. One thing it does not mean, by the way, is easier access to oil. It turns out that an Arctic with less ice is more dangerous to drilling rigs and oil platforms. Why? Because while pack ice is dangerous enough, less ice means very large pieces of ice floating and moving more quickly than in the past. It also means more stormy seas. So the Artic may turn out to be more difficult to fully exploit for fossil fuels than currently assumed (and yes, I am sure we all get the multiple levels of irony.)
To help us visualize the loss of ice volume Andy Lee Robinson has produced a nice little video showing the progression.
ht for compiling sources.