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Understanding Cold Water Risk - Richard Forbes, South Africa. Richard gives a good summary of hypothermia and its onset time for a range of water temperatures that will cover many paddling locales around the world and he talks about recent experiences from the Western Cape of South Africa and elsewhere. Although there are places with colder water than the Western Cape where people paddle and downwind where the colder water is objectively more dangerous in terms of reduced survival time for immersed paddlers, locales with somewhat warmer water can effectively be equally or more dangerous for paddlers if they tend to pay less attention to this risk and dress and/or prepare less carefully.
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Bellingham Winter Paddlers: Roger Lamb and Larry Bussinger - Click to enlarge