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Mariners Weather Log Vol Mariners Weather Log Vol. 44, No. 2 August 2000 The Jay Gould sank on June 17, 1918, near Southeast Shoal, Lake Erie, while towing the barge Commodore. All on board the two ships were rescued by passing steamboats. (See article on page 13.) Photo: Milwaukee Public Library. Mariners Weather Log Mariners Weather Log From the Editorial Supervisor This issue features an article on storm surge, which is the term used to describe the rise in still-water sea level that accompanies the landfall of a tropical storm or hurricane. Recognized as the single most destructive aspect of a hurricane, the coastal storm surge can cause much damage and loss of life (nine out of ten hurricane U.S. Department of Commerce deaths result from drowning in storm surge). The low Norman Y. Mineta, Secretary pressure in the eye literally sucks the ocean surface upward, like liquid through a straw, and vast tracts of National Oceanic and low-lying coastal terrain can be inundated with water as Atmospheric Administration the eye of the hurricane makes landfall. In the northern Dr. D. James Baker, Administrator hemisphere, the area just to the right of the storm track experiences the greatest rise in water level due to the added effect of the wind pushing the water. During the National Weather Service John J. Kelly, Jr., infamous hurricane Camille in 1969, a 25-foot storm Assistant Administrator for Weather Services surge inundated Pass Christian, Mississippi. Lesser heights are more usual, but still extremely dangerous. Editorial Supervisor Directly linked to a tropical storm’s central barometric Martin S. Baron pressure, storm surges typically range from 4 to 5 feet for a category 1 hurricane, to 9 to 12 feet for a category Editor 3 hurricane, to 18 feet and above for a category 5 Mary Ann Burke hurricane. See the article for more details. This issue also contains updated and newly revised information on communication methods for ships to transmit AMVER sail plan/position/deviation/arrival The Secretary of Commerce has determined that the publication of this reports. The AMVER record speaks for itself. Over the periodical is necessary in the transaction of the public business required by law last five years, AMVER has rescued over 1,500 people, of this department. Use of funds for printing this periodical has been approved by the director of the Office of Management and Budget through December most of whom would have perished if AMVER assis- 2000. tance had not been available. Safeguard your safety and The Mariners Weather Log (ISSN: 0025-3367) is published by the National that of fellow mariners by participating in AMVER. Weather Service, Office of Meteorology, Integrated Hydrometeorological Services Core, Silver Spring, Maryland, (301) 713-1677, Ext. 134. Funding is h provided by the National Weather Service. Data is provided by the National Martin S. Baron Climatic Data Center. Articles, photographs, and letters should be sent to: Some Important Webpage Addresses Mr. Martin S. Baron, Editorial Supervisor NOAA http://www.noaa.gov Mariners Weather Log National Weather Service http://www.nws.noaa.gov AMVER Program http://www.amver.com National Weather Service, NOAA VOS Program http://www.vos.noaa.gov 1325 East-West Highway, Room 14108 SEAS Program http://seas.nos.noaa.gov/seas/ Silver Spring, MD 20910 Mariners Weather Log http://www.nws.noaa.gov/om/ mwl/mwl.htm Phone: (301) 713-1677 Ext. 134 Marine Dissemination http://www.nws.noaa.gov/om/ Fax: (301) 713-1598 marine/home.htm E-mail: [email protected] See these webpages for further links. 2 Mariners Weather Log Mariners Weather Log Table of Contents The Perfect Storm Surge ................................................................................................................ 4 Great Lakes Wrecks: The Jay Gould .......................................................................................... 13 Harvesting the Sea—Aquaculture Offers a Supplement to Traditional Fisheries ............................................................................................................... 14 Departments: AMVER............................................................................................................................................................. 17 Marine Weather Review Technical Terms ................................................................................................................................... 19 North Atlantic, January–April 2000 .................................................................................................... 20 North Pacific, January–April 2000 ...................................................................................................... 32 Tropical Atlantic and Tropical East Pacific, January–April 2000 ....................................................... 46 Climate Prediction Center, January–April 2000 ..................................................................................58 National Data Buoy Center................................................................................................................................ 60 Coastal Forecast Office News ............................................................................................................................ 62 VOS Program .................................................................................................................................................... 66 VOS Cooperative Ship Reports ......................................................................................................................... 83 Buoy Climatological Data Summary ................................................................................................................. 94 Meteorological Services Observations ......................................................................................................................................... 98 Forecasts ............................................................................................................................................. 101 August 2000 3 Physical Oceanography The Perfect Storm Surge Bruce Parker National Ocean Service ver the centuries, the of sea walls and dikes has also tial rains caused flooding and deadliest and most reduced the likelihood of exten- mudslides that killed 11,000 in Odestructive element of a sive damage in some populated Honduras and Nicaragua), the hurricane has been the storm areas, although there is always the deadliest hurricanes in history surge, the huge mass of water, possibility of a storm more have wreaked their havoc through often tens of miles wide and many powerful than those structures storm surges. feet high, that is driven onto the were designed for. Storm surge, land by the high winds and low however, still remains the most The deadliest hurricane in U.S. pressure of the storm. Combined serious threat to all low-lying history was the hurricane that with the astronomical tide, the coastal areas where hurricanes or wiped out half the city of resulting storm tide has time and extratropical storms can threaten. Galveston, Texas, in September time again throughout history 1900, killing at least 6,000 and caused massive flooding, inundat- Although storm surge was not the perhaps even thousands more than ing coastal areas for miles inland, main cause of death or damage in that because so many people were destroying buildings, and drown- the last two major hurricanes in never found (remains were ing people. With today’s satellite- North America, Andrew in August unearthed for years following that and model-based warning systems, 1991 (high winds caused billions storm). In this case a 6 meter (20 evacuations have greatly dimin- of dollars in damage in southern ft) storm surge had come in like a ished casualties, at least in the Florida) and Mitch on 26 October bulldozer that literally scoured developed countries. The building through 4 November 1998 (torren- Continued on Page 5 4 Mariners Weather Log Physical Oceanography The Perfect Storm Surge The deadliest hurricane (or killed approximately 10,000 Continued from Page 4 cyclone as it is called in the Indian people and made a million people Ocean) in this century was in homeless. For reasons we will see whole city blocks out of existence. Bangladesh in November 1970 below, out of 23 cases of major With its deep harbor, Galveston when, in a horrifying episode of hurricane disasters around the had been a thriving port and one human loss, more than 300,000 world (with human death tolls of of the largest cities in the U.S. people were killed in the low- 10,000 or more), 20 have occurred After the hurricane, the primary lying deltas of the Ganges River along the coast of the Bay of port moved upstream to Houston. by a huge storm surge estimated to Bengal. The worst of the worst The move to Houston required the be over 9 m (30 ft) high. Sadly may have been the storm surge in dredging of a deep-water ship again in May 1991, 138,000 more 1876 produced by the Bakerganj channel, but at least it was in a people died there from a hurricane Cyclone of Bangladesh, which safer location than Galveston. with a 6 m (20 ft) storm surge. was estimated to have killed After the hurricane a 3 m (10 ft) Year after year other cyclones approximately 2 million people. sea wall was built to protect producing other storm surges have The aftermath of such storm Galveston, but in August 1915 taken lives in the northern Bay of surges—shattered buildings and another violent hurricane pro- Bengal in both Bangladesh
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