I occasionally use a Garmin wristwatch type of GPS while biking or hiking. Today I finally put it on my sea kayak; I wanted to measure the distance between launch point and dam. Not wanting to study the online user manual, I left the display as usual: Time of day, miles traveled, avg speed, and altitude gain.
Weeeellllllll…didja know that a reservoir somehow has 220 ft elevation gain in 10 miles round trip? Hmmm! Funny, I thought flatwater was, well, FLAT.
Could those 220 ft result from a few dinky boat waves and tiny wind waves?
Or is it barometric pressure change? The weather was fair, though there is a slight chance of showers overnight into Sunday.
Would the “altitude gain” indicate dropping barometric pressure?