Water Temperatures & Hypothemia

During the colder months water temperatures can cool down to the point where hypothermia can occur. Winter kayaking may have the advantage of peace and quiet on the water, and making alligators and snakes lethargic, but the kayaker needs to consider the remote possibility of capsizing. In 5 years of kayaking, I have never capsized, even against wakes from large vessels, but it can happen to anyone. When in the water, body heat is lost 25 times faster than in air. The best thing you can do when finding yourself unexpectedly in cold water is to get out of it, or at least get as much of your body out as possible. The greatest heat losses occur from the head, chest, and groin. Blood vessels in arms and legs constrict to save heat and concentrate blood flow to vital organs. Keeping any clothing on and using a life vest will reduce heat loss. For cold water kayaking in situations where there will be an increased chance of getting capsized, (large waves, open ocean, ect.) consider wearing a wetsuit. Extreme cold water kayakers may even wear a drysuit. There are two basic types of wetsuits, for watersports (kayaking, surfing ect), and for diving. The kayaking/surfing suits are thinner and more flexible, while the diving suits are thicker and thus less flexible, but will keep you warmer. The "shorty" wetsuit has short sleeves and legs and covers only the torso. A "farmer john" wetsuit has long legs and resembles overalls. A full wetsuit will have both long legs and sleeves. These are supplemented with booties, hoods, gloves, and in the case of the farmer john, a jacket. Extreme cold water kayakers often use a drysuit which covers everything but the face and is a whole lot more expensive. Perhaps the biggest problem with any type of suit is when you have to urinate or worse, since it is not easy getting in or out of suits. Trying to do so while in the kayak is as risky as taking off a jacket while driving a car. You risk getting tangled up or capsizing. It's best to find an island. If you find yourself in the unlucky position of being in the water, try to get out quickly before the hypothermia makes it difficult to move numb legs or arms. Other effects of hypothermia include: strong shivering, blue skin (from loss of blood flow), reduced pulse and heartbeat, lack of coordination, and the most dangerous, mental confusion. Huddling together will help to conserve body heat. A single person should float with the head out of the water with legs tucked up to your body and your front facing slightly up. The "deadman's float" where you curl up with your back up and head in the water, lifting head up periodically to breathe, is a warm water technique only. Having the head submerged will increase your heat loss. Swimming for shore is a judgement call, depending on how far it is to land, and whether you'll be fighting a current or waves. The act of swimming will deplete your heat faster as you travel through the water, and wear you out quicker. google-site-verification: googleb3a55d1fb5d05d13.html

*saltwater freezes at 28.4 degrees

Effects of Hypothermia

The following table is from the U.S. Navy Diving Manual:

Wetsuit Thickness

Wetsuit thicknesses vary from ultralight 1-2 mm to medium 3-5mm, and very cold water 6-8mm. The thicker the suit, the warmer you'll be. However, thicker suits have reduced flexibility. Kayaking wetsuits are available commercially that are designed for flexibility. Scuba wetsuits have different design criteria, as do surfing wetsuits. In water under 50 degrees, wetsuits are less effective and drysuits are a better choice. Water temperatures usually don't get much colder than 45 degrees at the northernmost parts of the state.

Current Statewide Water Temperatures

Link to NOAA Water Temperature Observations:

http://www.nodc.noaa.gov/dsdt/cwtg/egof_tmap.html

Wind Chill Chart

From the U.S. Navy Dive Manual