Hi all. I found an article that may be of historical interest. This is in BAMS in 1943 and is called “Forecasting The State of the Sea and Swell”. It is interesting as a snapshot before the publication of the Sverdrup-Munk method. There was rough understanding that wave height needed to be a function of fetch as well as wind speed. 1520-0477-24_6_239 (1).pdf (2.5 MB)
They also describe a summary of the French swell prediction by Lt. Lacroix in La Revue Maratime in Feb. 1937. I can’t track it down, but I’d be interested to read it if anyone can find it. (I am aware of the earlier papers by Gain and Montagne.)
ThanksTripp.
Usually all french publications should be archived by the Bibliotheque Nationale, which has a really good online collection ( https://gallica.bnf.fr ) this is where I could find the papers by Gain and Montagne … but they do not appear to have the 1937 issues available online : Revue maritime (Paris) - 20 années disponibles - Gallica
Also, I’m hoping to go to Casablanca for teaching in October … I’ll try to find the time to look for local archives.
Fabrice
Thanks Fabrice. You mentioned under the Gelci thread that you were looking for early swell dissipation studies? Deacon Ocean Waves and Swell.pdf (485.5 KB)
In the attachment, GER Deacon mentions the work of Commander Suthons:
“On a coast which is exposed to ocean swell the effect of the swell from storms, even
several thousands of miles distant, may be more important than the effect of local winds.
An approximate rule formulated by Commander Suthons of the Naval Meteorological Service
states that swell loses 1/3 of its height in travelling a distance which, measured in nautical
miles, has the same numerical value as the wave-length measured in feet. Swells longer than
1,000 feet are common, and these will lose only 1/3 of their height in travelling 1,000 miles.
The famous rollers of Ascension and St. Helena are very spectacular, and have caused great
damage, in spite of the fact that they have travelled at least 3,000-4,000 miles.”
Charles Bates, who was one of the wave forecasters for D-Day has written a good amount about the whole affair. Apparently, Suthons produced an empirical wave forecast method before Sverdrup and Munk. Sverdrup and Munk ran a metocean forecasting training program for officers. Munk used to say they would learn so much from the students that they would rewrite the course every month. I think it likely they were exposed to Suthon’s method and maybe integrated some of his ideas into their method, but it’s hard to say for certain. When it came time to choose a method, the forecasters tried both Suthon’s method and Sverdrup-Munk method, finding the latter a little more accurate and easier to use. I found a reference in the British National Archive, which may be Suthon’s work, but it is not available digitally.