edited 3/12/11 to add references and some links
We are surrounded by waves: electromagnetic, light, radio, and water. They can be helpful providing power, light and communication; but they can also carry unimaginable force.
The science of waves and surf forecasting is relatively new. It began in earnest during WW II when scientists realized that successful amphibious landings required some ability to forecast surf sizes on the beaches. It didn’t hurt that there was oodles of money available and scientists, no different than anyone else, like nothing better than to specialize in something that has practical applications for war.
Reports of huge, 100-foot waves have traditionally been dismissed as typical seafaring exaggeration. Shackleton reported having his ship tossed about by the largest wave he had ever seen and one that towered over his ship. Large, seemingly unsinkable ships have disappeared without a trace. One ship that did, the Munchen, left a lifeboat that had been torn from its davits and which normally was suspended 65 feet off the deck. And yet, the physics of waves didn’t predict the possibility of such waves except in extraordinarily rare circumstances, so rare, as to be literally incredible.
Technically a “rogue wave inn oceanography, is more precicely defined as waves whose height is more than twice the significant wave height (SWH), which is itself defined as the mean of the largest third of waves in a wave record.”
A scientific discovery ship aptly named the Discovery was tossed around like match wood in a storm on the way to Iceland. Fortunately the captain was able to save the 200 foot vessel which was layered with scientific instruments which recorded periodic waves of 100 feet among normal sets measuring 45 feet.
Jan 1, 1995 something happened that made scientists reconsider. On a platform in the North Sea. Seas were high, running around 38 feet as measured by instruments on the platforms underside until an 85 foot wave hit the rig at 45 mph coming out of nowhere. The first confirmed measurement of a freak wave, more than twice the size of its neighbors. The engineers who designed the rig had built it for the one-in-10,000 year 64 foot wave. 85 foot waves were not part of the equation. The emphasis soon shifted from whether these waves existed to how and why they occurred. An oil rig, the Ocean Ranger, went down off Newfoundland that had been designed to withstand 110 foot seas. There were no survivors. (Things were a little more complicated than just the wave according to this entry: http://en.wikipedia.org/wiki/Ocean_Ranger) Casey’s version is sensationalized and you have to take some of her descriptions with a dose of salt.
Interesting facts: two large ships sink every week, but the causes are usually just attributed to bad weather. Unlike when an aircraft goes down, rarely is there an investigation that’s more than cursory.
Casey alternates between science and the more prosaic, like surfing. (Her adulation for Laird Hamilton carries a sexual tension that should have had Laird’s wife, herself a striking former beach-volleyball pro, (http://gabriellereece619.typepad.com/blog/2010/10/gabrielle-reece-image.html) more than a little concerned. Their swim out to “Jaws” and back and then getting hosed off bordered on prurient.) Some of her similes border on the silly, likening a personal characteristic to being “as wide as interstate 10,” whatever the hell than means. We follow Laird around the world seeking the ever more thrilling ride, as Laird laments the ever-larger crowds, crutches like Surfline that forecasts huge swells with precision, and sponsors and contests. (It should be noted that Hamilton gets lots of endorsements so he can afford to be dismissive of those seeking greater glory.) There’s also little examination of the effect and controversy of tow-in surfing, really the only way to get to the right spot for gigantic waves. Hamilton’s long-time tow-in partner Derrick Doerner even though, as I understand it, he was a champion paddle-in surfer (true surfing??) many years before his connection to Hamilton. Perhaps he was less Adonis-like than Hamilton.
The answer to the formation of these freak/rogue waves was found in quantum physics and Schrödinger’s equation (for you math types: http://en.wikipedia.org/wiki/Schr%C3%B6dinger's_equation) which describes deep water waves (they have found some waves 600 feet high rumbling around below the surface) and surface waves that become unstable and a central wave will “rob energy from its neighbors” making the troughs on each side of the enormous wave very deep. (The BBC series cited below has some spectacular graphs showing this.) What makes these waves especially dangerous for ships is that they aren’t the typical waves with sloping sides that ships are designed to handle. Rather, these have very steep sides and deep toughs on either side. The captain of the Queen Mary who saw one of these said it reminded him of the cliffs of Dover, straight up. And they break, which means you have millions of tons of water dropping on you, about 100 tons per sq. meter as opposed to a 12 meter wave that’s about 6 tons per sq. meter. (That would make a great Disney ride although it would be guaranteed to bring on massive puking.)
For the truly paranoid or apocalypticly oriented types, I recommend reading the section on the side of the mountain in the Canary Islands that's due to collapse into the ocean generating a 100 foot wave along the east coast of the United States; or, Latuya Bay in Alaska that generated a 1,000 (yes, that's one thousand) foot high wave following an earthquake in 1958. I mean, really. (The USC Tsunami Research Group found evidence the wave may actually have been 1,720 feet high. - http://www.usc.edu/dept/tsunamis/alaska/1958/webpages/lituyacloseup.html - I thought Casey was exaggerating so I had to look it up. The wave snapped trees that were six-feet thick.)
Perhaps my favorite part of the book was the section on salvage tugs and their crews. Those who have read other reviews of mine will understand the attraction I have for these stories. Farley Mowat wrote a wonderful novel about ocean-going salvage tugs: The Grey Seas Under: The Perilous Rescue Mission of a N.A. Salvage Tug. One of the hazards Mowat doesn’t even mention was dealing with dangerous cargo. The worst is undeclared pesticides or herbicides. The regulations in carrying such cargo are so onerous –and properly so– that the incentive to carry them illegally is huge. When a ferry, the Princess of the Stars – capsized off the Philippines the salvage experts discovered an extremely hazardous pesticide, Endosulfin, that would have caused devastation on a nearby Sibuyon Island, environmentally pristine sanctuary. Other hazardous cargo such as phenyl, a common ingredient in plastic causes paralysis when its fumes are inhaled. In one case cyanide powder had been labeled as flour.
These intrepid souls head out in the absolute worst weather to rescue ships in distress (For a great video of one such French ocean-going tug see: http://www.youtube.com/watch?v=w8K2B1nRRyA&feature=fvst. (I get seasick just watching this video, notice the wave breaking on the bridge.) For a high seas rescue check out the video of the Flandre’s sister ship, the Bourbon: http://www.youtube.com/watch?v=T5Na8EY1irA.
For a very unusual salvage story see In Peril: A Daring Decision, a Captain's Resolve, and the Salvage that Made History
I would have preferred a little more science (the title is misleading, it’s really more hagiography of Laird Hamilton) and a little less surfing (I'm exaggerating a little, perhaps I'm just jealous.) She’s a good writer although I should point out one never says 25 knots per hour; 25 miles per hour or 25 knots. John McPhee, Casey is not. Nevertheless, it’s a fascinating read.
Confirmed from space: http://news.bbc.co.uk/2/hi/science/nature/3917539.stm
The BBC has a nifty series of videos with some great footage at http://www.youtube.com/watch?v=Htq57DK1YrE&feature=related
Popular Mechanics article Dec 1972 “Little Boats that Go Out to Save Big Ones”: http://books.google.com/books?id=69QDAAAAMBAJ&pg=PA84&dq=ocean+salvage+tugs&hl=en&ei=y818TfjcNcjkrAG6uYXXBQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDoQ6AEwAA#v=onepage&q=ocean%20salvage%20tugs&f=false