The first link Murkywaters provided also shows COLD water in Curaçao in March, 81 degrees F (the AVERAGE temp, not necessarily the temp on 24 March 1998).
Hypothermia is very much a possibility when, as I demonstrated in links I provided, cold water immersion happens to a person's body. The immersion in cold water lowers body temperature quicker than body temperature is lowered in the air environment.
The second link she provided states: "Cold water dangerously accelerates the onset and progression of hypothermia since body heat can be lost 25 times faster in cold water than in cold air. Hypothermia affects the body's core – the brain, heart, lungs, and other vital organs. Even a mild case of hypothermia diminishes a victim’s physical and mental abilities, thus increasing the risk of accidents. Severe hypothermia may result in unconsciousness and possibly death."
Thank you, Murkywaters. Excellent sleuthing helping to point to a hypothermia theory. I appreciate the back up research into the hypothermia angle.
Amy would have had no life vest, no flotation device, she was likely wearing cotton, she presumably hadn't eaten in many hours, she had little body fat, she may have been dehydrated if she had been drinking and she possibly would have been injured during the fall or when she hit the water.
I hadn't run across any links about a canal, as several links I posted said the ship was ten miles offshore when she went missing. Nevertheless, she wasn't found in the canal and one possibility for that is that she didn't fall in the canal. You can't find someone if you are searching the wrong area, and most people who fall overboard are never found regardless of the search effort.
The second link, with survival times, is a boating link for Minnesota's lakes and inlets. Boaters are required to have:
1) a free standing personal flotation device which can be thrown to a person or will fall into the water if something happens to the boat
2) a life jacket for each person on the boat. (In most states, boaters are not required to wear the PFD at all times, but you do have to have one for each person).
The difference between having a PFD and not having a PFD is a significant factor in life vs. death and also those survival times do NOT account for injury. It is assumed the person in the lake is not injured.
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"Hypothermia is a medical emergency that occurs when your body loses heat faster than it can produce heat, causing a dangerously low body temperature. Normal body temperature is around 98.6 F (37 C). Hypothermia (hi-poe-THUR-me-uh) occurs as your body temperature passes below 95 F (35 C).
When your body temperature drops, your heart, nervous system and other organs can't work normally. Left untreated, hypothermia can eventually lead to complete failure of your heart and respiratory system and to death."
http://www.mayoclinic.org/diseases-conditions/hypothermia/basics/definition/con-20020453