Sunday, April 18, 2010

Eyjafjallajökull eruption: gorgeous video

The NY Times Lede blog has linked to BBC Channel 4 video of the eruption. From the look of it, the videographer had one of the many excursion drivers take them up Thórsmörk (or Þórsmörk) valley on the north side up high enough to look at the eruption without dealing with the jokulhaup (or glacial flood) in the river. If you have ADD you will miss the active sub-Plinian eruption and great lightning in latter half of the video.

UPDATE: the waterfall at the beginning is Seljalandsfoss. I have a photo of it here:

EDIT: calling it sub-Plinian.

Eyjafjallajökull eruption: planes vs. volcano

An interesting data point about the Eyjafjallajökull eruption: the disruption of the European aviation market reduces the CO2 output by an order of magnitude more than the CO2 released by the volcano itself,


Saturday, April 17, 2010

Moments in spaceflight

Soichi Noguchi captures a poignant moment as the Shuttle leaves the International Space Station. Click to enlarge to a higher quality image.

Bye! on Twitpic

Thursday, April 15, 2010

Eyjafjallajökull eruption

I was just reading about the Eyjafjallajökull eruption yesterday and the rather bold tourist enterprise sprung up to visit it, when I see it has erupted in an explosive manner. The new path to the surface for the magma opened under the ice sheet (jokull) instead of bare ground, and water/magma interactions produce copious amounts of gas. Gas is a bad thing when it comes to magma. It makes thing go boom. Instead of a lava fountain and a tourist stop in Iceland, now we have flooding as the glacier melts, and air travel restrictions as the volcano generates large plumes up into the atmosphere from the phreatic eruption. The Icelanders are concerned about the flooding and the fluorine from the ashfall. For the geology, the composition of the magma (how much silica is in it, how much gas is in it), its interaction with the surrounding rock, and how the magma changes in composition as time increases are the interesting things. For the British sitting waiting for the air to clear, realize that ash is just magma pulverized through explosive means. Blame the gas.

Here is some good information on the location and the inflation/deflation data.

Thursday, April 01, 2010

Geiger counter problems interfacing with PC

I've been unable to get the DOS software AW-SRAD to work with the geiger counter for some time, on multiple machines, with Windows XP. It's a bummer. I can input the sound pulses from the clicker unit I made into a sound card, but I have no idea how to then get the PC to do something with that. I'm not a programmer. The original geiger counter set up was really simple: it toggled the RING indicator on the serial port.