Saturday, December 15, 2007

EEs explain rogue waves

WoW! I have been away from blogging for just a little over three weeks and it feels more like three months.

Its been a busy time both in business and personally for me. I will have some more news about both very shortly.

But in the meantime there is weather and marine news out there.

Yes winter has arrived! Just ask anyone still without power in the mid west right now or living in Boston. Today NWS Chicago is reporting 3 to 5" of snow with lake effect. The heaviest will be during the overnight hours into Sunday. Though the temps and winds so far have not been as nasty as they can get and I am sure that is coming soon.

Talking about nasty. Here is a video of the impact of falling ice during last weeks ice storm in the mid west. Lesson Learned here? Look up when parking your car after you have been warned! This was shot by Storm Chaser and WX-Chase Moderator Chris Novy!


Killer Ice - Watch more free videos


Our featured article of today..


EEs explain rogue waves
By EE Times

R. Colin Johnson
(12/14/2007 2:28 PM EST)
URL: http://www.eetimes.com/showArticle.jhtml?articleID=204803618


Rogue waves as high as a 10-story building have been offered as an explanation for the disappearance of ships as big as an ocean liner, despite the lack of survivors to tell the tale. Recently, remote sensors set up in the oceans of the world have confirmed that single rogue waves as tall as 100 feet occur more frequently than Gaussian statistics can explain. For the first time EEs have generated rogue waves in optical fibers and have confirmed the mechanism that generates them, which they say can occur in other media too, including the ocean.

"Rogue waves are an apparently random phenomenon that is seeded by noise," said lead investigator on the project Daniel Solli, a researcher at the University of California at Los Angeles (UCLA) Henry Samueli School of Engineering and Applied Science. "We have shown that noise with the correct properties can foster the generation of one of these rogue waves."

According to Solli and Bahram Jalali, a UCLA professor of electrical engineering and the research group leader, rogue waves are analogous to the butterfly effect, a phenomenon in which, under the right initial conditions, a butterfly flapping its wings can cause a hurricane. Of course, these initial conditions are exceedingly rare, but the bottom line for the butterfly effect, according to Solli and Jalali, is that weather is very sensitive to initial conditions, as is the generation of rogue waves.

"Like the weather, these rogue waves appear to be extremely sensitive to initial conditions," said Solli. "It is still a deterministic system, but one that is very difficult to predict, because a very, very minute change in initial conditions can have a dramatic impact on the result."

Researchers studying a microstructured optical fiber near the threshold of soliton-based supercontinuum generation observed the generation of rogue waves in the optical fiber, and they began modeling the mechanism. As a result, the researchers have now characterized the proper initial conditions for generating rogue waves in any medium.

"We show that a particular set of initial conditions are responsible for generating rogue waves," said Solli. "In our experiment we discovered that we were getting some rare events that were far larger than any of the neighboring pulses, and that led us to explore this connection between this phenomenon and the oceanic phenomenon which has a very similar kind of effect."

According to the researchers, rogue waves follow "L-shaped" statistics, as opposed to the more common Gaussian statistics. This accounts for the seemingly out-of-bounds size of rogue waves: in L-shaped distributions the heights of most waves are tightly clustered together, but large outliers also occur. Now Jalali's team is working on a more detailed model for the U.S. Department of Defense, which is aiming to harness the effect for military applications.

"The next step is learning how to engineer this phenomenon, because there must be some useful applications out there, if only we could predictably engineer the outcome of this event, which occurs very rarely now," said Jalali.

Other member of Jalali's team include UCLA engineering researchers Claus Ropers and Prakash Koonath. Funding is being provided by the U.S. Department of Defense and the Defense Advanced Research Projects Agency (DARPA)

Tropical Storm Olga

Seems like Tropical Storm Olga has made her stake in weather history as reported by Arthur Rabjohn CEM, Director Steelhenge Consulting Ltd.
www.steelhenge.co.uk

CARIBBEAN: Caribbean storm death toll rises

People were swept away in Santiago when flood waters were released The toll in the Caribbean from Tropical Storm Olga, a rare December cyclone, has risen to at least 38 confirmed deaths, officials say. Hardest hit was the Dominican Republic, where at least 35 people have been killed by floods and landslides. The death toll rose again on Friday after the bodies of 12 immigrants from neighbouring Haiti were discovered in Castanuelas, a town near the border. The UN has urgently appealed for $4m (£2m) to help the many left homeless.

National Hurricane Center Reports

NHC releases 2007 seasonal summaryNOAA also releases seasonal report


On the maritime front..

The main feature story of this blog has been the rescue of the s/v Sean Seamour II, that I have focused on is about to make news again. The USCG helicopter crew that rescued the three sailors from their potential watery graves during subtropical storm Andrea this past May are about to get decorated for heroism on December 19 at USCG Air Station Elizabeth City. I will have more as soon as the new medals are placed on their salad bars.



Swimmer Drew Dazzo in the helicopter resting before being evacuated with us to Cherry Point Military hospital for injuries sustained during our rescue, AC Lt. Comdr. Nevada Smith supervising the transfer while coordinating with operations.


KAB 101

Here is a shot many of you may not have seen of the KAB 101 incident
that we reported about back on October 29th and 30th. when reported large waves struck Mexico state-owned drilling platform Usumacinta which slammed into the Kab 101 Light-Production Rig on Oct. 24, killing 21 people.


On the weather lighter side....

If global warming, greenhouse effects, jet stream changes or just plain lousy winter weather or any lousy weather for that matter does not confuse you enough? Let's just add good ole Pat Robinson to the equation. The bad weather we are having is because?



RS

No comments: