Morgans wrote:
Surfers wear wetsuits in 70 deg. water. It's cold enough to produce
hypothermia in 6-12 hours of exposure.

Something has gotten lost in the translation, I think.

The water temp of 70 degrees is at 30 feet of depth. At the surface, it is
much warmer. It does indeed get very warm at the surface, at the beaches.


Surface water is probably much warmer but any water less than body temperature
will eventually draw off heat. Back in my young and stupid days, I used to
scuba dive in rock quarries. The surface temp would typically be about 80-85
degrees in the summer, quite comfortable in just a swimsuit. Once you dropped
below the thermocline, the water temperature would drop a good 35 degrees in the
span of just a couple of feet's worth of depth. 45 degree water is damned cold
even in a wetsuit with full hood and gloves. 85 degrees is damned hot in a
wetsuit with full hood and gloves.

Thermoclines in those quarries were usually in the 15-25 foot range in the
summertime. Of course in the winter, there is no thermocline... it's cold from
top to bottom.

Water temps in the ocean off the NC coast are similar at the surface but they
don't have a thermocline until maybe 80 feet or so. Even then the temp doesn't
drop more than maybe 10 degrees or so.

70 degree water is rather bracing but feels good when the air is hot and humid.
However, you can't handle it for more than an hour or so without getting
chilled.

Now, how far were they going to have to swim in Lake Erie?



--
Mortimer Schnerd, RN

VE