A few years ago, I was leading a hiking trip in a national park when one client and a team leader sled down from the park’s tallest sand dune (a common, typically enjoyable activity in the park). But ...

Sara Goulden was freezing to death, literally. Her vital signs were weak, she was drifting into unconsciousness and she had stopped shivering — all symptoms of severe hypothermia. Snow blanketed the ...