posted 03-20-2007 04:36 PM ET (US)        

What's fascinating is that doing a Google Search on Wave Height Measurement returned the following link from CW in the third return: http://continuouswave.com/ubb/Forum1/HTML/003611.html .

Water waves are measured from crest to trough, not mid-poing, as are radio waves.

For an interesting perspective about the apparent sizes of waves from a small boat, consider the "sitting on the floor" advice found here: http://www.guillemot-kayaks.com/guillemot/information/ kayaking_technique/small_boat_and_kayak_navigation/ determining_wave_height .

An 8 foot wave in a small boat can look like a tsunami.

Another group of seagoers who are keenly interested in waves and wave height are surfers. This large community has developed some great information about waves, given their interest in selecting and riding the "best" waves. They agree that wave height is measured from trough to crest. They also point out another important factor for Boston Whaler operators: wave period. See: http://www.stormsurf.com/page2/tutorials/wavebasics.shtml

Also; when listening to a weather forecast, it is important to know that they are talking about "significant wave height," which is equal to the highest 1/3 of waves. So it is likely you will encounter waves that are much larger and much smaller than the forecast. i.e. if there are forecast 3 footers, you may see a passing 6 to 8 footer in there! This is especially important in boats less than 20 feet. Also important is wave steepness. Steep waves are "rougher" than swells of the same height.