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other sea surface characteristics, could be observed by using the exist- 

 ing satellite vehicles. 



Our coastal radar system finds and tracks ocean storms, and repre- 

 sents a critical and indispensable protective network for hurricane 

 warnings. Special observations from the cooperative hurricane net- 

 works along the Atlantic and gulf coasts as well as our tide gage net- 

 works play major roles in our national hurricane warning service. 



ESSA strives constantly to get up-to-date information to as many 

 mariners as possible. This is accomxplished through it own broadcast 

 system, those of other public agencies, and other media. Visual dis- 

 plays at more than 550 stations also warn of approaching storms. In 

 the offing are broadcasts of weather maps and prognostic charts by 

 radio facsimile to ships on the high seas. 



Our marine environmental prediction services may be divided into 

 four broad categories : high seas shippiing, Great Lakes marine activi- 

 ties, commercial fishing, and marine activities within coastal waters 

 and inland waterways. 



Marine weather and sea-state warnings, forecasts and reports are 

 prepared and broadcast daily from coastal points to merchant 

 shipping. 



Forecasts, warnings and weather summaries are issued routinely for 

 each of the Great Lakes. In the spring, the Weather Bureau office at 

 Detroit predicts the opening date for free-ice navigation into eight 

 principal ports : Detroit, Alpena, Cleveland, Marquette, Sault Sainte 

 Marie, Green Bay, Duluth, Buffalo. 



Support to commercial fishing is offered through 6-hourly 

 general-area forecasts by Weather Bureau offices as Boston, Washing- 

 ton, Miami, New Orleans, and San Juan. These include Avind direction 

 and speed, weather, visibility and, when necessary, sea-state conditions. 



Weather forecast and warning bulletins are issued at 6-hour inter- 

 vals for coastal waters up to 50 miles offshore. They are broadcast by 

 the Coast Guard, marine radiotelegraph and radiotelephone shore 

 stations, and more than 2,000 commercial radio and television stations. 

 Dissemination is also provided by nine new ESSA VHF-FM marine 

 weather broadcast stations: Miami, Honolulu, San Francisco, New 

 York, Chicago, Washington, Corpus Christi, Galveston, Jacksonville. 

 Stations at New Orleans and Lake Charles, La., are to be installed 

 momentarily. These are continuous broadcasts of vital information. A 

 total of 19 will be operating within the next year and one-half. 



Hurricane and tropical weather outlook reports, and poststorm 

 reports, are issued by the National Hurricane Service from Miami, 

 Washington, Boston, New Orleans, San Juan, San Francisco, and 

 Honolulu. They include information on amounts of flooding expected, 

 wave action, or beach erosion. 



Such storms can raise sea level far above normal height as they ap- 

 proach the coast. To assist in prediction of the storm surge, ESSA has 

 remoted and automated tide transmitting equipment on a number of 

 gages and recorders in 14 offices. Tide observations are available on 

 request from 115 other tide stations along the gulf and Atlantic coasts. 



The tsunami, or seismic sea wave, caused by undersea seismic phe- 

 nomena, can produce lethal waves which can crest at over 100 feet. 

 Tsunamis are relatively rare but extremely dangerous. Honolulu is 



