Museum of Underwater Art

Want a bit of culture on your next dive? Then try the tropical blue waters of Cancun, Mexico where you will find the Museum of Underwater Modern Art.Consisting of more than 403 permanent life-sized sculptures, the art-filled sea-bed is one of the largest artificial reef attractions in the world. The work of British sculptor and scuba diver Jason deCaires Taylor, each sculpture is individually cast and made using a special cement mix to encourage coral growth. "It's incredibly interesting working underwater," said deCaires Taylor. "The colors are different, the light patterns are very different, the atmosphere and mood is otherworldly.

"The piece takes on a very different tone underwater -- it has a lost feel to it and brings up all these questions that you wouldn't have on land,"

Peeing In your Wetsuit

Why do you always feel like you have to pee in your wet suit!? Like me, most scuba divers feel the need to urinate in their wetsuits. What's wrong with us? Are we drinking too much water? Do we simply have no self control? No! One reason that divers feel the need to urinate in their wetsuits underwater is called cold water immersion diaresis.

Although the total volume of blood in the diver's body has not changed, the volume of blood in his body core (particularly his heart) has increased. This triggers the body's high blood volume management system, which mainly involves increasing the rate of urine production in the kidneys (diaresis) as discussed above. The end result is that the diver pees in his wetsuit. No Big Deal! :)

So don't be embarrassed by your urge to urinate while diving. What's my advice for comfortable diving? Buy your own wetsuit, hydrate yourself before diving so your urine doesn't smell bad, and pee as much as you like. Urine is sterile so you are not going to create a health hazard if you pee in your suit. Simply remember to wash your suit in fresh water after diving (and not in the same rinse tank as the regulators, please!) Everyone else is peeing in their suits, why should you miss out on all the fun?

Staying Warm Underwater

Water conducts heat from the diver 25 times better than air, which can lead to hypothermia even in mild water temperatures. Symptoms of hypothermia include impaired judgment and dexterity, which can quickly become deadly in an aquatic environment. In all but the warmest waters, divers need the thermal insulation provided by wetsuits or drysuits.

In the case of a wetsuit, the suit is designed to minimize heat loss. Wetsuits are generally made of neoprene that has small gas cells, generally nitrogen, trapped in it during the manufacturing process. The poor thermal conductivity of this expanded cell neoprene means that wetsuits reduce loss of body heat by conduction to the surrounding water. The neoprene in this case acts as an insulator.

The second way in which wetsuits reduce heat loss is to trap a thin layer of water between the diver's skin and the insulating suit itself. Body heat then heats the trapped water. Provided the wetsuit is reasonably well-sealed at all openings (neck, wrists, legs), this reduces water flow over the surface of the skin, reducing loss of body heat by convection, and therefore keeps the diver warm (this is the principle employed in the use of a "Semi-Dry")

Drysuits fall into two main categories neoprene and membrane; both systems have their good and bad points but its really personal preference. Like I have previously said, go into your local dive store and ask them a little about wet suits. Most places will rent wet suits for cheap and then you can get a feel for what you like. Depending on the amount of dives you do in colder water will determine the density. Check out your local dealers today! 

Underwater Communication

Table of Hand Signals

A diver cannot talk underwater unless he is wearing a full-face mask, but divers can communicate, using hand signals. It is said that if a diver "signals to his buddy regularly during a dive, this will ensure that they remain in close contact and that they can easily notify each other in case problems occur."; a diver should repeat any sign that is not clear to his buddy, and acknowledge every signal that he or she makes with an "OK" signal to show that he understands.

No.	Signal	Meaning	Comment
1.	Hand raised, fingers pointed up, palm to receiver.	STOP	Transmitted in the same way as a traffic police officer’s STOP
2.	Thumb extended downward from clenched fist.	GO DOWN or GOING DOWN
3.	Thumb extended upward from clenched fist.	GO UP or GOING UP
4.	Thumb and forefinger making a circle with three remaining fingers extended (if possible).	OK! or OK?	Divers wearing mittens may not be able to extend 3 remaining fingers distinctly.
5.	Two arms extended overhead with finger tips touching above head to make a large O shape.	OK! or OK?	A diver with only one free arm may make this signal by extending that arm overhead with finger tips touching top of head to make the O shape. Signal is for long-range use.
6.	Hand flat, fingers together, palm down, thumb sticking out, then hand rocking back and forth on axis of forearm.	SOMETHING IS WRONG	This is the opposite of OK! The signal does not indicate emergency.
7.	Hand waving over head (may also thrash hand on water).	DISTRESS	Indicates immediate aid required.
8.	Fist pounding on chest.	LOW ON AIR	indicates signaler's air supply is reduced.
9.	Hand slashing or chopping throat.	OUT OF AIR	Indicates that the signaler cannot breathe.
10.	Clenched fist on arm extended in direction of danger.	DANGER

Make sure that you review hand signals with your dive partner before your dive so there is no miscommunication underwater. 

Just For Fun

Controlling Buoyancy Underwater

To dive safely, divers must control their rate of descent and ascent in the water. Ignoring other forces such as water currents and swimming, the diver's overall buoyancy determines whether he ascends or descends. Equipment such as the diving weighting systems, diving suits and buoyancy compensator's can be used to adjust the overall buoyancy. When divers want to remain at constant depth, they try to achieve neutral buoyancy. This minimizes gas consumption caused by swimming to maintain depth.
The downward force on the diver is the weight of the diver and his equipment minus the weight of the same volume of the liquid that he is displacing; if the result is negative, that force is upwards. The buoyancy of any object immersed in water is also affected by the density of the water. The density of fresh water is about 3% less than that of ocean water. Therefore, divers who are neutrally buoyant at one dive destination (e.g. a fresh water lake) will predictably be positively or negatively buoyant at destinations with different water densities (e.g. a tropical coral reef).

The main thing to remember with buoyancy is that you should always check your weight at the beginning of the dive so that you are comfortable throughout the entire dive. Use your fins to swim and hold your arms across your chest as shown in this picture. You will loose a lot less oxygen and be able to dive longer. Remember that buoyancy takes time to adjust to at first so don't get frustrated. In time you will learn all the tricks of the trade.

Octopus Fun

• Octopuses are boneless creatures. They don't have a vertebral column, that is, they are invertebrates. The beak which is in the shape of a parrot beak, is the only hard structure in their body. Due to this reason, their bodies are extremely flexible and they can squeeze through incredibly small spaces.
• Octopuses vary in size depending upon the species. While those found in tropical waters are small, octopuses of the colder seas are larger in size. The giant Pacific octopus is the largest amongst all the members of the group and are known to grow as large as 23 feet. However, most octopuses are smaller in size. Usually they grow up to 10 feet and weigh around 55 ponds. Females are smaller than the males.
• An interesting octopus fact is that these sea creatures have three hearts. Two hearts pump blood through the gills whereas the third one pumps blood through rest of the body.
• The color of octopus blood is blue.
• The octopus is a predator. It hunts at night. Its favorite food are crabs, mollusks and crayfish.
• Octopuses are preyed upon by sharks, dolphins, morays and conger eels.
• These eight legged creatures have highly developed sense of sight that helps them to hunt efficiently in the low light levels of the deep waters. They also have an excellent sense of touch. Octopuses have sensory receptors at the bottom of their suckers that enable them to "taste" whatever they touch. They are, however, deaf.
• Male octopuses die within a few months of mating. However, males of larger species live longer. Female octopuses die soon after their eggs hatch.
• The most remarkable octopus fact is that they have a number of defense mechanisms. They can change the color of their body to merge with the surrounding that helps them to stay invisible from prey or predators. The first instinct of an octopus, when threatened, is to flee. Octopuses are known to eject a cloud of black ink when attacked by a predator. Sometimes they may also shed an arm to escape a predator. The lost arm regrows in some time.