The Thermodynamics of Scuba

Scuba divers are amazing people. They need to know meteorology to understand weather patterns and how weather affects the seas. They need to understand how depth and pressure are interrelated. They must understand basic medicine as it relates to barotrauma, and first aid for those unlikely accidents. They must be conversant on the hundreds of plants and and animals that occupy this harsh environment. They need to apply basic navigation skills and techniques. They must be physically capable of handling 60 to 80 pounds of extra weight on a rocking boat. Finally, they need to understand the physics of thermodynamics, the subject of this article.

Even if you don't profess to know much about science, you already know all about thermodynamics, the science of heat transfer. But first a little history. In 1868, Carl Wunderlich published his findings whereby he measured the temperatures of hundreds of healthy individuals over several years, and concluded that the average healthy person's internal or core temperature centered around 37 degrees Celsius. This translates to 98.6 degrees on the Fahrenheit scale, a so-called "normal" temperature. We will use Fahrenheit throughout this article. Normal temperature can vary plus or minus a degree, depending on age and physical activity, but generally, your body functions well when it's core temperature hovers around that average. Your skin temperature is several degrees cooler than your core. It will range from around 87 degrees near your chest and abdomen, to around 84 degrees at your extremities.

Back to thermodynamics. A surface is either a heat source or a heat sink. A heat source gives off heat, while a heat sink absorbs heat. Heat travels from a source to a sink. The transfer of heat from source to sink will continue until both are at the same temperature, a condition known as equilibrium.

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Lower Keys Diving

--by Jerry Kosakowski

The lower Keys are a little bit of a drive for a one day expedition, but it has much to offer. For us scuba divers the number one attraction is the wreck, the Adolphus Busch Sr. This is a former cargo freighter sunk in 1998. It is 210 feet long and only three dive shops go to it. It is fully intact.

The Looe key Artificial Reef association bought it and towed it from Haiti. It was cleaned up and specially prepared for divers in Miami. Originally named the Ocean Alley, the Anheuser-Busch corporation provided the funding for the undertaking. Since Busch provided funding, they got to pick the name for it. Funny how that works.

It is safe for light penetration and stands upright in 110 feet. It has 12 large holes that make it easy to penetrate and swim through the ship. It is loaded with fish and moray eels, and there are three goliath groupers that frequent the wreck. All this makes for a great dive experience. Place it on your “dives sites to visit” list if you haven’t yet visited it.

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ADA to Tour the Turtle Hospital in Marathon on July 22nd

The Turtle Hospital is a small non-profit organization dedicated to the rehabilitation of endangered sea turtles. It's goals are: 1) Rescue, rehab, and release sick and injured sea turtles. 2) Educate the public through outreach events and local schools. 3) Conduct and assist with research aiding to sea turtles. 4) Work toward legislation making the beaches and water safe and clean.

The Hospital is built on the grounds of the old Hidden Harbor Mote in Marathon, FL. The motel rooms serve as living quarters for their rehab staff and storage. There are several small pools for patients and The Turtle Hospital is a fully-functioning veterinary hospital with two very large outdoor pools. The most common injuries treated at the turtle hospital are caused by humans. These include boat strikes, fishing line entanglement and fibropapilloma tumors caused by fertilizer runoff.

Sea turtles that are deemed non-releasable by the Florida Fish & Wildlife Conservation Commission (FWC) are permanent residents of The Turtle Hospital. The most common reason for permanent residency is bubble butt syndrome caused by boat strikes. Boat strikes creates an air cavity in the shell which makes the turtle positively buoyant and unable to dive. Thus they cannot forage for food and must live out the rest of their lives at The Turtle Hospital.

ADA is planning a special tour to The Turtle Hospital on Saturday, July 22nd at 9:00 a.m. for those attending the Looe Key/Key West weekend. The tour lasts 90 minutes and will be over in plenty of time to drive 20 miles south to Looe Key Resort and have lunch before the dive check-in. The tour provides a presentation on sea turtles as well as a behind the scenes look at the hospital facilities and rehabilitation area. There are also educational exhibits about turtle conservation and how we can prevent illnesses and injuries to sea turtle populations. At the end of each program guests are invited to feed the permanent residents.

Tour admission is $22 per person, payable directly to The Turtle Hospital upon arrival, which is located 2396 Overseas Highway Marathon, FL 33050, MM 48.5 Call Rachel Davis at 786-316-9852 or email rachelhancock7@gmail.com to sign up for the tour. We look forward to seeing you there!

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Every diver loes colorful coral reefs teeming with marine life.  But if you have been diving in the Florida Keys for less than thirty years, you missed the reefs when they were the most beautiful.  From the late Seventies until the mid Eighties, a combination of factors led to a drastic drop in reef-building corals, leaving the reefs bleached and scattered, nearly facing extinction. Ships running aground over shallow reefs, warming and polluted waters, and the demise of the spiny sea urchin, which helped clean away choking algae, along with other stressors, rendered the reefs much less beautiful for divers and less hospitable for fish and other sea life.  But for more than ten years the Active Divers Association, through the volunteer efforts of members like yourself, has been working to reverse that decimation of the reefs and to restore them to their former health and beauty.  This is your chance to do your part in our next restoration project on September 9.

Since 2007 the ADA has been supporting and participating in the reef restoration activities of the Coral Restoration Foundation (“CRF”), a not-for-profit research and conservation organization led by Ken Nedimyer.  CRF works to restore our coral reefs, educate others on the importance of our oceans, and uses science to further research and monitoring techniques. CRF is a world leader in the marine sciences dedicated to creating offshore nurseries and restoration programs for threatened coral species. These programs have allowed CRF to take the lead in innovative nursery and restoration techniques that are implemented worldwide.

Through propagation techniques, tens of thousands of corals are grown and maintained in multiple offshore coral tree nurseries before being strategically outplanted on reefs allowing them to continue on a path to natural recovery. With the help of students, volunteers, scientists, and donors, baby corals are successfully raised until they are “reef-ready”, outplanted onto the reef, and monitored. These innovative techniques are being duplicated in other oceans and making a difference for reef systems worldwide.

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Dive Etiquette

--by Mo Smith

Boat charters survive by maximizing the number of divers on each dive trip.  Frequently, charter boat real estate is minimal and divers have to strategically utilize their gear space.  These are some tips that can help a diver navigate through a dive trip by using proper etiquette resulting in a successful day on the water.

• Arrive on Time – Typically a diver should arrive 30 to 60 minutes prior to the boat departure time, to minimize departure delays. During this time, the diver should complete any necessary paperwork and gather all gear required for the dive trip. With sufficient time to prepare, diver anxiety is diminished.


• Organize Your Boat Space – Minimize space used by organizing your gear.  I like to secure my gear within my BC.  After setting up my gear, my fins are placed vertically inside the chest cavity area of my BC, my mask is clipped onto the chest strap, and my weights and dive bag are placed on the floor just underneath my seat.  This protects my gear from damage and allows space to my next-door neighbors.


• Secure your Tank – Most charters have some way to secure your dive tank after you’ve set up your gear.  Make sure you secure the gear in the dive operator’s prescribed manner to prevent it from falling over during travel.  This will prevent damage or injuries.


• Listen to the Dive Briefing - Each Charter has a unique way of handling their divers and provide specific information regarding emergencies, entering/exiting the dive boat, length of dive time, and other important information.  Even if you have heard the briefing before, it is not appropriate to continue to speak while the other divers are trying to listen.


• Use the Correct Rinse Bin – Dive boats usually have two water filled bins.  One bin is used for cameras, and the other for mask rinsing.  It is inappropriate to place your mask in the camera bin.  The chemicals in the defog used on your mask can harm delicate camera parts.


• Be a Helpful Neighbor – If a neighbor needs assistance, be helpful if appropriate, or contact the boat Dive Master.


• When Diving be Aware of your surroundings – Don’t separate from your dive buddy, be cognizant of the reef, and prevent damage.  On occasion look back, if you see a cloud of sand you are the one creating that plume with your fins, so adjust your buoyancy or fin kick.  This damages the environment and prevents divers behind you from enjoying the dive area.  Don’t touch, don’t stand, and don’t take are good rules to follow.


• Return on Time – Dive charters are on a schedule and the longer you take in returning to the boat from the dive, the shorter the second dive will be. All the divers, not just you, have paid to dive.  Your late return diminishes their dive time.


• Be Polite – When using the boat shower be aware of the other divers in the immediate area.  Shower downwind and prevent spraying them with water, possibly causing damage to uncovered cameras, or wetting dry clothes or dive logs.

Following these simple rules will make you a better dive neighbor and fulfill what will be an enjoyable day in the water.

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