Sunday, April 18, 2010

Planeless sky

The unpronounceable Icelandic volcano has left my place of work quite empty. This last week was the largest demography conference of the year, and a large portion of my colleagues flew to Dallas for it. They have not been able to return.

This map (from the NYTimes) shows which European airports are currently closed. Rostock is right in the middle of the gray area, half way between Berlin and Copenhagen. The closest operating airports right now are Madrid (2500km), Rome (1700 km including crossing the Alps) or St. Petersburg (2 days by ferry), and they are all booked up. So I may not have many coworkers around until this dust blows over.

The sunsets have been colorful the last couple of days, and the horizon looks hazier than usual, but other than that and the lack of airplanes flying over, I can see no smoke. Also, the grocery stores are out of bananas.

The airlines are starting to question the science behind the flight ban. I am doubtful myself. The concentration of particles (which hasn't actually been measured in most places) must be pretty minute, as the emissions from a small eruption are dispersed over perhaps 100,000,000 cubic kilometers.

I come to that rough estimate because the effected area is about 5000km east to west, 5000km north to south and the cloud is about 4 km top to bottom. I've not seen an estimate for how many tons of ash are up there, or what concentration is dangerous, but I'm guessing the concentration of particulate matter up there is no higher than that over LA or Houston in the summer.