Did you know ?

A graphic way to visualize what can happen in a diver's body if the pressure of the surroundings is reduced too suddenly is to recall what happens in a bottle of soda when the top is removed quickly. The pressure that held the gas—carbon dioxide in soft drinks—in solution suddenly drops and the gas comes out of the solution in a burst of bubbles, flowing out over the top of the bottle.

Such a sudden release of pressure isn't only a hazard for divers, but also can be a danger in unpressurized civilian aircraft and high-flying military planes. Our bodies are saturated with nitrogen all the time, no matter the altitude at which we live. If an unpressurized airplane (usually a small, privately owned plane) rises quickly to altitudes of more than about 18,000 feet (5,500 meters) above sea level, that dissolved nitrogen can form bubbles, and the pilot and passengers suddenly find themselves dealing with the bends, even though they may be breathing oxygen to compensate for the thinner atmosphere. The solution is, of course, to come down to a lower altitude. Altitude-induced decompression sickness can also threaten military personnel who sometimes must work in depressurized sections of aircraft for a while, such as when a cargo door is opened for parachutists or an airdrop. In these instances, personnel who will be working in the unpressurized area breathe pure oxygen for a carefully regulated time period before the plane rises above a dangerous altitude, just as the aquanauts in Aquarius spent three 20-minute periods breathing oxygen at the beginning of their decompression. In each case, whether the person is high above the Earth or beneath the ocean's surface, the oxygen forces some of the dissolved nitrogen out of the body and reduces the chance of getting decompression sickness.

—Patricia Kellogg

Power Failure Photograph by Brian Skerry When the lights blink off and air circulators fall silent, operations manager Jim Buckley radios mission control in Key Largo 10 miles (20 kilometers) away. Speeding to the rescue, the support crew discovers that moisture in the fuel has shut down one of the generators in the life-support buoy moored above Aquarius. "Losing power is not an issue with our guests, the scientists," says Buckley. "The most stressed people are the crew who have to come out and restart the systems."
Power Failure
Photograph by Brian Skerry

When the lights blink off and air circulators fall silent, operations manager Jim Buckley radios mission control in Key Largo 10 miles (20 kilometers) away. Speeding to the rescue, the support crew discovers that moisture in the fuel has shut down one of the generators in the life-support buoy moored above Aquarius. "Losing power is not an issue with our guests, the scientists," says Buckley. "The most stressed people are the crew who have to come out and restart the systems."

 

Fishy Science
Photograph by Brian Skerry

Passing red sponges that now paint Aquarius, a Spanish hogfish bears a scar on its belly where a tiny transmitter was inserted. Inside the habitat a computer picks up the transmitter's signals, allowing aquanauts to track fish as they move into, around, and out of the study area. "We have to understand the movement patterns of different species to design marine reserves that protect them," says Les Kaufman. "There's a lot to learn, but already we've begun to think more like fish."
 

Seabed Surgery
Photograph by Brian Skerry

Aquanauts close an incision after implanting a tracking transmitter in an anesthetized Spanish hogfish. When they finish, one will stay with the fish, moving it through the water by hand to help its gills flush out the anesthetic. "I've tagged a lot of fish in a lot of different ways," says Les Kaufman of Boston University, "but I've never seen such an excellent response as when I've done it underwater in this manner." All of his two dozen subjects swam away vigorously. Signals from their transmitters showed that they mostly stayed inside their protected home waters around Aquarius.
 

Tight Quarters
Photograph by Brian Skerry

Just three feet wide by 18 feet (five meters) long, the corridor in the main compartment of Aquarius doesn't leave much room for maneuvering. "To make it work right, you have to choreograph your moves," says the New England Aquarium's Ken Mallory, at right. "We feel liberated when we enter the wide open space of the ocean." After swimming like fish, the aquanauts sleep like sardines, stacked in bunks that flank the porthole at the far end of the habitat.
 

Close Encounters
Photograph by Brian Skerry

Aquarius has gone native since its installation on Conch Reef in the Florida Keys in 1993. Coral and sponges cover much of its legs and hull, and schools of fish treat it like a section of the reef itself. Seeing the daily parade of neighborhood residents—like this column of schoolmaster snappers—gives the aquanauts a constant education in what creatures live here and how each plays a part in the ecosystem.
 

Total Immersion
Photograph by Brian Skerry

Like an underwater RV, the Aquarius habitat lets half a dozen scientists live some 50 feet (20 meters) beneath the sea's surface five miles (eight kilometers) off the south coast of Florida. Normally scientists can only visit this world on short dives from the surface. As aquanauts, they spend up to nine hours a day conducting research in the water. In the end, though, they pay for their stay: During their final 16.5 hours the habitat becomes a decompression chamber that gradually reconditions them to live on dry land.
 

What's the best way to study Florida's coral reefs and their finned inhabitants? Live where the action is by Gregory Stone

We were 85 feet (26 meters) underwater and more than five miles (eight kilometers) off the Florida coast when the lights went out. It was night, and conservationist Craig Taylor and I had been diving for two hours by the dim beams of the Aquarius research station—our underwater home and, at that depth, our only safe haven. About the size of a railroad freight car, Aquarius looked like a spaceship on the seafloor, an interior glow filling her view ports, exterior spotlights illuminating her sides and legs. When she lost power, she simply disappeared into the inky blackness, and I felt as cut off from the world as an astronaut stranded in space.

I fought the impulse to head for the surface, which is what scuba divers are trained to do when they get into trouble, because this was no ordinary dive. For the past four days we'd been living in Aquarius as aquanauts, and by now our bodies were saturated with nitrogen. If I surfaced quickly, without decompression, dissolved nitrogen in my body would expand from the sharp decrease in pressure, forming bubbles that could painfully squeeze nerves, block blood flow, or cause brain damage. Decompression sickness probably would kill me.

Suddenly Aquarius's emergency siren started wailing—a signal for all aquanauts to return immediately. The piercing sound, however, seemed to come from all directions. Breathing heavily on my scuba tanks as I swam through the darkness, I used my emergency lights to search for the web of excursion lines that had been mapped out for us during our one-week training session. These guidelines were a safety measure to help us navigate around the reef. Grasping a black braided rope in one gloved hand, Craig and I followed the line back to the station, where we felt our way across the coral-and-algae-covered metal to the rectangular opening in the bottom known as the moon pool.

The station functions like an inverted glass pushed down into a bucket of water: An air pocket remains at the top of the glass while the glass remains upright. The crew maintains the air pressure inside Aquarius at the same high pressure as the surrounding ocean, keeping the water from rushing in. We lived in that air pocket, which I was eager to get back to. Emerging from the ocean water, I stood waist-deep in the moon pool, removed my regulator, and breathed in the hot, humid air from Aquarius.

"Generator's down," said Christian Petersen, a U.S. Navy diving medical officer, as he stood above me in the dim emergency lighting. Without power from either of the two electric generators in the life-support buoy tethered above us on the surface, we had only dim emergency lights and no air-conditioning. In these warm tropical waters, with a half dozen people inside, our small laboratory would rapidly become stifling. I climbed up the stainless steel steps, peeled off my dive gear, and began to sweat.

Pictures of an underwater hotel 5 

Pictures of an underwater hotel 4 

Pictures of an underwater hotel 

Amongs the corals and tropical fish 

Another Big Wednesday / ambrose
Mavericks photos by - Frank Quirarte©2001
11/21/01  

BodyBoarding pictures -Another Big Wednesday / burle_bomb1
Mavericks photos by - Frank Quirarte©2001
11/21/01 

Another Big Wednesday / brasil_on_the_run
Mavericks photos by - Frank Quirarte©2001
11/21/01 

BodyBoarding pictures - Another Big Wednesday / big_flea
Mavericks photos by - Frank Quirarte©2001
11/21/01 

Another Big Wednesday / barney_barrrel
Mavericks photos by - Frank Quirarte©2001
11/21/01 

Mavericks photos by - Frank Quirarte©2001
11/21/01
 

Collecting under water specimens from the maya grave site .  

Too Close for Comfort
Photograph by Wes Skiles

U.S. biologist Tom Morris, wearing side-mounted scuba gear, creeps along a freshwater chamber beneath the sea—a space so narrow that his air tank bumps along the floor as his helmet scrapes the ceiling. Morris and Wes Skiles penetrated this undersea fountain passage for about a half mile, starting from the open sea and ending up beneath the coastline. The passageway was oriented, they discovered, along the fault line of the meteorite's impact rim.
 

The Hunt for Hidden Entryways
Photograph by Wes Skiles

Exploring among the mangrove swamps of Yucatán's north shore, photographer Wes Skiles's documentary team scouts for freshwater springs that may be connected to the ring of cenotes. The team eventually came across natural fountains that connected to a vast underground system of caves and passages.
 

Octavio del Río, one of the cenote survey project co-directors, sketches details of a Maya skull that lies in the debris of a cenote in the northern Yucatán Peninsula. The victim may have been a human sacrifice, perhaps to Chac, the Maya god of rain, who lived in the underworld. Probing 20 or so cenotes in ancient Maya territory, expedition scientists concluded that small-town Maya followed the religious customs of grand cities such as Chichén Itzá, and that cenotes were vital to their sense of eternity.
 

A Map of the Maya under water Cave complex  

Watery Graves og\f the Maya 

Adventure, climbing and folly

My reaction to the accidental death of K. Duminda Thabrew while attempting to climb down from the Diyaluma Waterfall was that it amounted to an act of folly.

Gamka has sent me the following note in reply:

"For a desk-bound type like you, for whom crossing the road on any given day amounts to an adventure and who needs the lift to go from the first floor to the ground, this will of course amount to folly. But I maintain that there are degrees of folly, and let's see just how mad this act looks with the benefit of hindsight.

"One thing I must say: Anyone out to set a record need not take foolhardly risks. What I mean by that is this; he or she must go properly equipped for the attempt, and basic safety features must be adhered to. A safety rope is essential to anyone serious about climbing, whether it's descent or ascent.

"I don't know why this young man began his descent from the top of Diyaluma, which is 628-ft high, without a safety rope. Was that meant to be part of the record? The question is not meant to be fatuous. Consider that, for those who want to climb the Himalayas, oxygen tanks are considered to be essential because of the rarified air at those heights.

There are many who'd consider any such attempt without oxygen to be foolhardy, even suicidal. But there are a number of people who have climbed the Everest without oxygen, and have lived to tell the tale.

One Nepalese sherpa has done it no less than six times, which I believe is a record. But all the people who have climbed the Everest without an extra oxygen supply are, it goes without saying, highly experienced climbers.

It also goes without saying that even such people can die while trying to scale such heights (due to accidents and bad weather rather than lack of oxygen). It'd be interesting to find out, especially to an armchair adventurer like you, if Mallory, the first man to try and climb the Everest, did so with extra oxygen. As far as I know, the kind of portable cylinders with regulators to control the supply in keeping with fluctuations of outside atmospheric pressure didn't exist at the time.

This invention came during the Second World War, more than 10 years after Mallory's death, in the form of the aqualung, invented by French undersea explorer Jacques-Yves Cousteau and Emile Gagnan in 1943.

"You said something about the minimum safety features that should be adhered to when trying this sort of thing. Before going into that, I must say that I don't know if climbing down from waterfalls is an international sport. I'm not aware of any such thing.

"Usually, people try ascents. Descent follows naturally. Technically, climbing down isn't any easier than climbing down.

I'm not talking about walking down a sloping hill but going down a very steep hill or cliff face. I'm not a climber but hikers I've spoken to have told me so. (Don't take the staircase as a wonderful example of this principle. By the way, it's about time you attempted the ascent and descent between the ground floor and first).

"We don't know why Thabrew decided to climb down as a means of establishing his record, rather than climbing up. Quite possibly, because he thought it was more dangerous. Or he thought he could do it quicker that way. After all, he had climbed down from the Bambarakanda Waterfall last year in a similar attempt.

"In hindsight, of course, his fatal attempt can look foolhardy. The weather was bad. It was due to start at nine a.m. but he couldn't get going till 11 a.m. as it was raining. The rocky face of Diyaluma, slippery under normal circumstances, would have been very dangerous by then. He wore a waterproof suit and gloves but had no safety rope.

"Climbing down 628 feet under these circumstances would have required a superhuman effort from the arms and shoulders, as well as the hips and legs, plus prodigious amounts of physical dexterity, balance and concentration. Something went wrong and the man fell to his death.

Don't call him a fool. He knew the risk he was taking. On an altogether different plane, you know the risks of smoking and continue to smoke half a pack a day. What kind of fool are you?

"Nor can anyone impose minimum safety standards on such attempts. These attempts are acts of free will.

This reminds me of free diving, a very dangerous sport. In this, the diver goes down to depths exceeding 200 feet without oxygen tanks, managing only with a lungful of air till the dive is completed and surface reached once again.

The current world record is held by a woman. Divers have died while trying to create such records.

"Which doesn't mean one shouldn't attempt them if the will, mental and physical capacity as well as the belief that it can be done is there.

"In conclusion, Thabrew's act looks like folly because he fell to his death.

If he had succeeded, then he'd have been a hero, and someone else may have died trying to break his record, continuing the eternal cycle of heroism and folly at infinitum."

(http://www.dailymirror.lk/2004/10/06/life/5.asp)

Divers and scientists probe Yucatán sinkholes, sacred to the Maya, where human sacrifices ensured cosmic order By Priit J. Vesilind

On the third day it was my turn to test God's vigilance, letting the metal chair plop me down into the cool pond like a piece of bait. Treading water, I adjusted my eyes to the moonlight of the cave. The cenote was shaped like an old Chianti bottle—a narrow neck leading to a wide chamber about 90 feet (30 meters) across and 120 feet (40 meters) deep. The bottle was half full, the water surface 35 feet (11 meters) below the domed ceiling. Stalactites dripped, and the roots of trees were spread on the walls in delicate dark webbing. Spanish records tell how live victims were thrown into the sacred cenote at Chichén Itzá, a major Maya city, on the premise that, as sacrifices to the gods, they would not die—even though they were never seen again. I scanned the slick limestone walls, and my heart pounded, feeling their terror.

Sinking deeper into the white noise of pressure, I bottomed out at 50 feet (20 meters) and glided across piles of shattered limestone. A side cave, shaped like a sock, spun down and off to the west. Resting in the sand was a mahogany-hued skeleton, already tagged, the eye orbits of its skull bleak with expectations of eternity.

A few days later the National Instutute of Anthropology and History scientists brought him up. It was the first skeleton of its kind—with all its bones in their natural positions, undisturbed—ever found underwater in the Yucatán. He was a large man, perhaps 50 years old, well past the Maya life expectancy. "His health was bad," said Terrazas after examining the bones, "with arthritis so severe that he could barely flex his hands. He had terrible teeth problems—gingivitis—and he probably had a very hard time chewing."

He was lying face up on the sand. Was it an accident? "No," said Terrazas. "There are nine skeletons down there [eight are partial]. Maybe one is there from an accident, but not nine."

When the car winch pulled up the bones of the old man, the three women who had made quesadillas for us the previous night were standing by the well. I asked them what they thought of our mission. "We didn't expect skeletons," said one, Olegaria Chiku. "For us, a cenote is just a hole with water. But my mother lived around here, and she said that we needed to give the cenote 15 virgins, and God would open up a road to bring in the gold that we know is down there."

Until the 1960s many people, including many archaeologists, thought virgins were the only individuals whose stories had ended in the cenotes. "We learned then that they were not all young girls," said Carmen Rojas, the underwater archaeologist who oversees data processing for the survey project. "And now we know that they were not all sacrifices."

Chris King shares his tips on surfing in Sri Lanka (THURSDAY , 20th March 200)

The winter season for the south and south west coast - Hikkaduwa, Midigama etc is November to March. Beyond March and you get into the monsoon season which we had on a few evenings. Nothing drastic, just heavy rain for 30 mins or so but I guess it gets worse. The winds are more frequently onshore after March.

Finding accomodation is easy room prices range from £1.50 per night (basic double bed, fan, shower and toilet) right on the beach to £30+ per night. There are hotels all along the main and only street ! in Hikkaduwa.

We just turned up at the airport and shared a taxi with another couple with boards who were on the same flight. The taxi took about 3 hrs due to the traffic (unbeliveable - bikes, mopeds, ox and carts, lorries + chaos). Once in Hikkaduwa we found accomodation within 10 mins and paid around £2.50 per night.

My girlfiend now wife upgraded the accomodation to a villa for about £5.50 - £7.00 per night including breakfast. It had a balcony overlooking the beach and was a two minute jog down the beach to the reef. Meals cost from 50p !. Taxis known as 'tuk tuks' will get you anywhere for next to nothing.

After March there's surf on the East Coast at Arugam Bay but I didn't go there as the Tamel Tiger situation was a bit dodgy. There is a website for the surf shop at Hikkaduwa - search for surf/sri lanka and you should find it along with photos and I think accomodation above the shop which faces onto the main reef. The Lonely Planet guide for Sri Lanka has lots of detail on Hikkaduwa, hotels etc and even surfing.

Definitely a very warm, mellow and cheap surf spot once you get there !

Chris King

Dolphins clear mines the natural way By Alex Kirby ( BBC News Online environment correspondent)

Dolphins have been pressed into service in the coalition war effort in the Gulf.

The dolphins are basically like underwater sniffer dogs Major Andy Hopkinson

Two animals trained by the US Navy are helping to clear mines from the waters around the southern Iraqi port of Umm Qasr.

The coalition says the dolphins will help to make the port safe for aid cargoes and for other vessels.

The Navy says they are well cared for, and face little danger.

The dolphins are from the US Navy's Explosive Ordnance Disposal Mobile Unit Three (Eodmu 3), based in Coronado, California.

Nine have been flown to the Gulf, with a number of trained sea lions from the Navy's Mammal Maritime Unit in San Diego.

Two Atlantic bottlenose dolphins, called Tacoma and Makai, were taken by helicopter to Umm Qasr in fleece-lined slings, partially submerged in water tanks.

Makai has been at Eodmu 3 for 20 years, and Tacoma is described as one of the unit's most vocal animals. This is the first time any of Eodmu 3's animals have been used for mine clearance.

Helping the troops

They are trained not to touch any mines they find, but to mark them with floats. The Navy says they face no "significant" risk.

It says it uses dolphins because their biological sonar is far superior to human systems for detecting objects in the water and on the sea bed.

Sea lions are chosen for their very sensitive underwater hearing, and their ability to see in low light.

Major Andy Hopkinson, of the UK's Royal Logistic Corps, said: "The dolphins are basically like underwater sniffer dogs.

"The old port area was mined extensively during the Iran-Iraq war, and there's a fear that some of them may have sunk deep into the silt.

"When we are bringing humanitarian aid ships in, or any vessels for that matter, we need to be 100% sure the berths and channels are safe."

He said the dolphins were "pampered far better" than any champion from Crufts dog show would ever be.

No retirement prospects

Eodmu 3's website says: "The use of these animals' natural echolocation systems to locate objects in the water has proven effective and efficient at meeting many fleet requirements.

"The Navy will continue to use these systems as long as they are more effective than existing hardware."

The Navy has about 40 animals altogether, some trained to find mines, some to home in on objects like test torpedoes with acoustic pingers.

Another group specialises in detecting swimmers, and is used for protecting ships and harbours.

(BBC NEWS:http://news.bbc.co.uk/go/pr/fr/-/1/hi/sci/tech/2891629.stm)

Published: 2003/03/27 15:22:39 GMT

The lure of sun and sea By Leona Sutton

Last week I spent a few days relaxing in Nilaveli, about 30 minutes from Trincomalee. We just spent the days devouring books, sunbathing, swimming, collecting shells and dodging the cows and goats that joined us on the beach! As if there isn't enough room - the beach stretches 4km, but no! The goat decides to sit right next to me!

Anyway, on our third day we decided to take a boat over to Pigeon Island. We hired snorkeling equipment and plunged ourselves into the sea. As soon as my head went underwater and my eyes adjusted to its surroundings I was greeted by all varieties of fish, as well as weird and wonderful creatures: Huge groups of tiny black fish swam between my feet; florescent fish bobbed in and out of the coral, which swayed to and fro with the movement of the sea. It was all so beautiful.

As I (reluctantly) stumbled out of the water I kept falling over the dead coral that lay on the shore. It reminded me of bathrooms in the 80s; when everyone had a piece of coral sitting next to the rubber duck! I wondered how much damage this had caused and how much damaged I myself was actually causing by being there. As it turns out, quite a lot.

Although Sri Lanka owes much to its coral reef, attracting thousands of tourists every year, it appears that "us tourists" are doing more harm than good! Glass bottom boats are a popular attraction in areas such as Hikkaduwa. However, they are one of the biggest threats to the reef; wearing down the coral, damaging shallow areas. Snorkelers often can't help but put their feet down in the water. Therefore they damage and destroy hundreds of species in the process. Walking along the shore, excited tourists can't resist the temptation of turning a boulder over to view the little animals beneath them. Again, resulting in the death of many beautiful and sacred creatures.

Enjoying the safe way...

It is difficult to say what the perfect solution could be. However, it seems that a little common courtesy wouldn't go a-miss. People should be able to enjoy the beauty of Sri Lanka and its sea. However, we need to make sensible decisions when venturing out: Snorkeling and diving is an amazing experience, but we need to take as much care as possible:

• Try not to kick up the sand when snorkeling. Try and lie flat and keep your legs straight, avoid using your legs and arms.
• Before entering the sea make sure your mask and snorkel all fit correctly, this way you wont have to stop and adjust while in the water, thus avoiding contact with the coral.
• Avoid swimming in shallow areas.
• Do not feed fish, or ride the turtles.
• Do not take pieces of coral home (its nasty and tacky anyway!).
• If taking a boat, make sure it doesn't anchor on the reef.
• Don't throw anything over board.
• If you notice any damage, inform an organizer. This way you can help monitor the reef and its surroundings.
• Don't buy souvenirs from the tourist shops. They just encourage them to go out and hunt for more coral and shells.

I recently read Reef by Romesh Gunesekera. He described the sea and its creatures thus,

Flickering eyes, whirling tails, fish of a hundred colours darting and digging, sea snakes, sea-slugs, tentacles spouting and grasping everywhere. It was a jungle of writhing shapes, magnified and distorted, growing at every move, looming out of the unknown, startling in its hidden brilliance.

The sea really is a beautiful place and we should all have the opportunity to see it. However, if we don't respect and take care, Gunesekera's observations will simply be a comment on the past.