Retireing to the East Coast

The Cumbre Vieja volcano in the Canary Islands has received a lot of attention as a potential mega-tsunami generator. The premise is that it is a steep sided, active volcanic island with identified zones of weakness running approximately north-south that if she blows may result in a large, fast moving landslide failure on the southwest side of the island. This is termed a flank collapse. Early work suggested that this flank collapse could cause a tsunami event that would reach the southeast US about 8-11 hours after the failure. Along the Carolina and Florida coast with a complete rapid detachment of the landslide, initial modeling suggested 25-30 m of water will come ashore. (http://www.geo.arizona.edu/~andyf/LaPalma/doomsday.html)

With time, additional analyses and additional capabilities, these numbers have changed significantly. In the most recent studies (Harris, Grilli et.al. 2013) the times are shorter and the water height smaller. We are now at 6.9 hours and about 3.25 meters in Florida.

Cumbre Vieja has erupted several times in the recent past, in 1585, 1646, 1677, 1712, 1949 and 1971. The magma source for this volcano is deep and there has been only relatively minor seismic activity on the island. The next eruptions may tell the tale. If they are relatively low energy eruptions through existing vents, the opportunity for a flank collapse is low but the opportunity for gathering more information is high. If the next event is significant, keep the boats handy if you are a US East Coaster.

Americas Cup 34

So in the end, Larry Ellison had more money than the Islands of New Zealand. Not to take away from the tenacity, ability and courage of the crew, but in the end, the faster boat won. The engineering and technology (and money) that Oracle Team US brought to the table were just too much for the NZ team. Whatever changes Oracle made on the lay day made the upwind speed of Oracle 17 insurmountable. In the upwind legs, it was not strategy that won, but boat speed. Granted, Oracle figured out (probably through engineering simulation) that if you foiled lower upwind you gained a bit of speed.

It would be nice in the next AC if at least half of the American crew happened to be Americans. Get the kids on the water!

Geologic Extinctions

For anybody that remembers the old blog, you may remember that I had gone down the path of geologic extinctions. In the Phanerozoic (last 542 million years) there have been 5 great extinctions and many minor extinctions. We use the Phanerozoic because that is the period that we have fossil records for.

  • 450 million years ago (mya) 85% of the marine life went south.
  • 374 mya 70-80% of the marine species became extinct.
  • 251 mya was the greatest mass extinction in earths history where 90% of all species and up to 99% of all animals are thought to have disappeared.
  • 200 mya most of the ammonites, half the genera of bivalves, many brachiopods and gastropods, 20% of foraminifera families, 80% of quadrupeds, and all conodonts became extinct. Since conodonts are extinct you probably aren’t familiar with them. They were the earliest vertebrate (backbone) animal having survived for 250 my until BANG — gone. The looked a bit like eels.
  • Of course, 65 mya the dinosaurs and 2/3 of all other species with a cumulative loss of about 80% of all life on earth bit the big one with a comet or asteroid taking the blame in current thinking.

Lots of ideas on what happened to cause these extinctions.

  • massive volcanism (eruption of flood basalts) and consequent alteration in atmosphere/ocean chemistry
  • impact of meteorites
  • variations in sea level
  • significant glaciation
  • release of methane or carbon dioxide due to melting of gas hydrates
  • changes in the large scale circulation of ocean water as the shape/continuity of ocean basins change due to plate motion
  • radiation from a nearby supernova

Keep in mind that while these extinctions happened relatively rapidly, relatively rapidly in geologic time is measured in 10’s of millions of years. Homo-Sapiens (us) have only been on earth about 200,000 years. So man may have appeared and may disappear in a period of time less than a great extinction took to complete.