Weekly Ocean News

16-20 October 2017

For Your Information

International ShakeOut Day -- This Thursday, 19 October 2017, has been designated International ShakeOut Day, in which people and organizations around the world are encouraged to practice "Drop, Cover, and Hold On" to reduce injury and death during earthquakes. Some coastal states including California and Washington are providing information on how to evacuate, survive and recover from tsunamis that could be generated along the coast by the earthquakes.
Worldwide GLOBE at Night 2017 Campaign is underway -- The tenth in the series of GLOBE at Night citizen-science campaigns for 2017 will continue through Friday, 20 October. GLOBE at Night is a worldwide, hands-on science and education program designed to encourage citizen-scientists worldwide to record the brightness of their night sky by matching the appearance of a constellation (Cygnus in the Northern Hemisphere and Grus in the Southern Hemisphere) with the seven magnitude/star charts of progressively fainter stars. Activity guides are also available. The GLOBE at night program is intended to raise public awareness of the impact of light pollution. The next series in the 2017 campaign is scheduled for 10-19 November 2017. [GLOBE at Night]
Oceanographic expeditions that made an impact -- This week's Supplemental Information ... In Greater Depth provides a historical perspective of some of the oceanographic expeditions that made an impact upon science, especially in terms of oceanography.

Ocean in the News

Eye on the tropics --- During the last week, tropical cyclone activity was confined to the North Atlantic and western North Pacific basins: :

In the North Atlantic Basin, the remnants of Tropical Depression Nate continued to spread widespread torrential rainfall across the Southeast at the start of last week. The NASA Hurricane Page has additional information and satellite images of Hurricane Nate.
At the start of last week, a tropical depression formed over the eastern North Atlantic that quickly became Tropical Storm Ophelia by last Monday afternoon. At the time, this fifteenth named tropical cyclone of 2017 in the Atlantic basin was located approximately 860 miles to the west-southwest of the Azores. By Wednesday evening, Ophelia became a hurricane, marking the tenth consecutive named tropical cyclone to become a hurricane in the Atlantic basin. This occurrence is the longest string since 1893. During the later part of the weak, Hurricane Ophelia intensified to a category 3 hurricane on the Saffir-Simpson Scale by Saturday afternoon as it traveled toward the northeast, passing 220 miles to the south of the Azores. On Sunday night, Ophelia had weakened to a category 1 hurricane, as it was approximately 840 miles to the northeast of the Azores, or 500 miles to the south-southwest of Mizen Head, Ireland. Current forecasts indicate that Hurricane Ophelia should become a powerful post-tropical cyclone by early Monday as it continues traveling toward the north-northeast and before crossing Ireland and the British Isles. The NASA Hurricane Page has additional information and satellite images of Hurricane Ophelia.
In the western North Pacific basin, Tropical Depression 23-W (TD-23W) made landfall along the northern coast of Vietnam approximately 180 miles to the south of Hanoi last Tuesday. See the NASA Hurricane Page for more information on TD-23W.
Another tropical depression formed late last week over the offshore waters approximately 260 miles to the northeast of Manila, the capital of the Philippines. This system quickly intensified to become Tropical Storm Khanun as it traveled westward, crossing the northern sections of Luzon Island. Khanun intensified to become a category 2 typhoon on the Saffir-Simpson Scale as it continued to track toward the west-northwest across the South China Sea. By Monday, Typhoon Khanun was located approximately 250 miles to the east of Hanoi, Vietnam. Khanun is forecast to make landfall along the northern Vietnam coast late Monday. Additional information and satellite images for Typhoon are available on the NASA Hurricane Page.

NOAA's lead hurricane season forecaster interviewed on current Atlantic hurricane season -- Dr. Gerry Bell, NOAA's lead hurricane season forecaster, was recently interviewed and asked to provide his view of the current Atlantic hurricane season, which has been very active with ten hurricanes, including five major hurricanes (category 3 or greater on the Saffir-Simpson Scale) and how this activity compares with the outlook that he and his colleagues provided in May and August. [NOAA Stories]
El Niño/Southern Oscillation (ENSO) Diagnostic Discussion & La Niña watch -- NOAA's Climate Prediction Center (CPC) and the International Research Institute for Climate and Society (IRI) recently released their El Niño/Southern Oscillation (ENSO) Diagnostic Discussion that showed ENSO-neutral conditions were observed to continue through September, indicating neither El Niño or La Niña conditions, as cooler than average surface waters expanded across the eastern and central equatorial Pacific Ocean. In addition, subsurface waters were also cooling. In addition to oceanic conditions, the tropical atmosphere also indicates ENSO conditions. Based upon their assessment of the various computer forecast models that they use, the CPC forecasters have continued a La Niña watch that indicates a 55 to 65 percent chance that a La Niña event will develop during this Northern Hemisphere fall and continue through the boreal winter of 2017-18.
An ENSO blog written by a CPC contractor describes how CPC and IRI forecasters have been monitoring the atmospheric circulation and the sea surface temperature patterns across the tropical Pacific basin. They believe that the current ENSO-neutral conditions could become a La Niña event during the late fall and early winter 2016-17 (in the Northern Hemisphere), which has led to their continuing a La Niña watch. The blog also has accompanying graphics. [NOAA Climate.gov News]
A detailed El Niño/Southern Oscillation Diagnostic Discussion with supporting maps and charts is available from CPC.
Forecasters with the Australian Bureau of Meteorology recently issued an updated ENSO forecast from a Southern Hemisphere perspective. They reported continuation of ENSO-neutral conditions. They noted that weakened trade winds had interrupted the cooling trend of surface waters. Furthermore, they felt that with the majority of forecast models indicating additional cooling during the last several months of 2017, a transition to La Niña conditions was possible in December, which corresponds to Southern Hemisphere summer. [Australian Government Bureau of Meteorology]
Hydrographic surveys of waters around California's Channel Islands are being conducted -- The NOAA Ship Rainier, one of the agency's four large hydrographic ships, has started making hydrographic surveys of the waters surrounding NOAA's Channel Islands National Marine Sanctuary as part of the Southern California Seafloor Mapping Initiative that is designed to fill in gaps the bathymetric and seafloor information and create a critical data layer for decision-making for a number of marine management fields. The Rainier has new multibeam echo sounders that will be used to update the nautical charts in the sanctuary and to help in habitat mapping. [NOAA Coast Survey]
A centuries-old case of mistaken identity in Chesapeake Bay is uncovered -- Scientists from NOAA and the Smithsonian Institution's National Museum of Natural History have recently discovered that some of the jellyfish that have been found in Chesapeake Bay, the nation's largest estuary, are not one, but two different species. The newly recognized bay nettle jellies (Chrysaora chesapeakei) are markedly smaller than their saltwater relatives (Chrysaora quinquecirrha), and have only half as many tentacles.[NOAA News]
International conference focuses upon marine protected areas and communities -- More than 1100 experts in marine protected areas from 59 countries met in Coquimbo, Chile for the 4th International Marine Protected Areas Congress (IMPAC4). The Congress consisted of workshops, symposia, knowledge sharing, celebrations, and networking. .... [NOAA National Marine Sanctuaries News]
Scientists use hydrophones to learn how deep beaked whales dive -- NOAA scientists from the Northeast Fisheries Science Center recently reported that they used a towed linear hydrophone array to document dive depths for Gervais' and True's beaked whales in the waters of the western North Atlantic off the southern New England coast. The team found that the average dive depth for Gervais' and True's beaked whales heard in the study was 870 meters (about 2,850 feet). [NOAA Fisheries Northeast Fisheries Science Center News]
Headway made in saltwater desalination technology -- Engineers at the University of Illinois report making progress in their development of a saltwater desalination process that borrows from battery technology and would be potentially cheaper that reverse osmosis. [University of Illinois News Bureau]
Warming ocean waters could lead to a 70-percent increase of financial loss due to hurricanes -- In a recent study published by researchers at the University of Vermont, financial losses caused by hurricanes could increase more than 70 percent by 2100 if the oceans warmed at a rate projected by the Intergovernmental Panel on Climate Change (IPCC). The study focused upon coastal counties in South Carolina located within 50 miles of the coastline, including the Charleston metropolitan area, that were subjected to model simulations hurricanes involving two scenarios. One scenario involved no changes in ocean temperature between 2005 and 2100, while the other had the ocean temperature change at a rate predicted by the IPCC's worst-case scenario. [University of Vermont News]
Ohio receives help responding to unusual harmful algal bloom -- A team of researchers from Bowling Green State University, the University of Toledo, the State University of New York College of Environmental Science and Forestry, the Ohio EPA, and Defiance College have received event response funds for the initial testing and monitoring of the harmful algal bloom (HAB) for toxins that was located in the waters of western Lake Erie offshore of Toledo, OH. This event response funding was provided by NOAA's National Centers for Coastal Ocean Science. [NOAA National Centers for Coastal Ocean Science News]
An All-Hazards Monitor-- This Web portal provides the user information from NOAA's National Weather Service, FAA and FEMA on current environmental events that may pose as hazards such as tropical weather, fire weather, marine weather, severe weather, drought and floods. [NOAA/NWS Daily Briefing]
Earthweek -- Diary of the Planet [earthweek.com]

Concept of the Week: Seiche Model

A seiche (pronounced "say-sh") is a rhythmic oscillation of water in an enclosed basin (e.g., bathtub, lake, or reservoir) or a partially enclosed coastal inlet (e.g., bay, harbor, or estuary). With this oscillation, the water level rises at one end of a basin while simultaneously dropping at the other end. A seiche episode may last from a few minutes to a few days. (Refer to your textbook for more on seiches.)

With a typical seiche in an enclosed basin, the water level near the center does not change at all but that is where the water exhibits its greatest horizontal movement; this is the location of a node. At either end of an enclosed basin, vertical motion of the water surface is greatest (with minimal horizontal movement of water); these are locations of antinodes. The motion of the water surface during a seiche is somewhat like that of a seesaw: The balance point of the seesaw does not move up or down (analogous to a node) while people seated at either end of the seesaw move up and down (analogous to an antinode).

The natural period of a seiche depends on the length and depth of the basin and generally ranges from minutes to hours. The period is directly proportional to basin length. For example, the natural period of a seiche in a small pond is considerably less than its period in a large coastal inlet. Also, for the same basin, the natural period is inversely proportional to water depth; that is, the period shortens as water deepens.

A 41-second mp4 video http://ametsoc.org/amsedu/ds-ocean/Seiche_Calculator.mp4 was produced providing a graphical simulation of a seiche by the University of Delaware's Seiche Calculator (http://www.coastal.udel.edu/faculty/rad/seiche.html ). The first demonstration on the video shows a case with the "Modal Number" set to 1 with a seiche in an enclosed basin. The second demonstration is for the "Modal Number" to 0.5, which would represent partially enclosed basins that usually have a node located at the mouth (rather than near the center) and an antinode at the landward end.

Historical Events:

16 October 1780...The most deadly Western Hemisphere hurricane on record raged across the Caribbean. It killed 22,000 people on the islands of Martinique, St. Eustatius, and Barbados. Thousands more died at sea. (National Weather Service files)
16 October 1877...Bjørn Helland-Hansen, the Norwegian pioneer of modern oceanography, was born on this date. His studies of the physical structure and dynamics of the ocean were instrumental in transforming oceanography from a descriptive science to one based on the principles of physics and chemistry. (Today in Science History)
16 October 1944...The 1944 Cuba - Florida hurricane, also known as the Pinar del Rio Hurricane, stuck western Cuba on this day as a Category 4 hurricane. This hurricane killed an estimated 300 people in Cuba and nine in Florida. This is currently the 7th costliest U.S. Atlantic hurricane with an estimated $40.6 billion in damage (adjusted to 2010 dollars). (National Weather Service files)
17 October 1997...Late on October 17, Super Typhoon Ivan attained its peak intensity with winds of 185 mph and an official barometric pressure of 905 millibars (26.72 inches of mercury) as it was traveling to the west-northwest toward Luzon in the Philippines. On the same day, while near peak intensity, Typhoon Joan was located about 1300 miles east of Typhoon Ivan. (National Weather Service files)
18 October 1910...Northeasterly winds as high as 70 mph (from a hurricane moving northward up the Florida peninsula) carried water out of Tampa Bay and the Hillsboro River. The water level lowered to nine feet below mean low water. Forty ships were grounded. (The Weather Channel)
18-19 October 2005...Hurricane Wilma developed a tiny, well-defined eye and began intensifying rapidly, reaching Category 5 strength with a record-setting pressure of 882 millibars (26.04 inches of mercury) by 19 October. The rapid intensification from tropical storm to Category 5 hurricane in 24 hours was the fastest ever recorded in the Atlantic Ocean, and the second-fastest worldwide, after Super Typhoon Forrest. (National Weather Service files)
19 October 1843...Captain Robert Stockton of the Princeton, the first screw propelled naval steamer, challenged the British merchant ship Great Western to a race off New York, which Princeton won easily. (Naval Historical Center)
20 October 1892...After ten years of difficult and costly construction, the St. George Reef Lighthouse, built on a rock lying six miles off the northern coast of California, midway between Capes Mendocino and Blanco, was first lighted. (USCG Historian's Office)
20 October 1956...A German physician, Dr. Hannes Lindemann, began a voyage on which he would become the first person to cross the Atlantic in the smallest craft. Using a double-seat folding kayak that was 17 feet in length and outfitted with an outrigger and sail, he made the trip from Las Palmas in the Canary Islands to St. Thomas in the US Virgin Islands in 72 days. He had made a prior crossing in a 23-foot African dugout canoe. He later wrote a book, Alone at Sea, describing his experiences. (Today in Science History)
20 October 1984...The Monterey Bay Aquarium opened on Cannery Row in Monterey, CA as the largest artificial environment for marine life, housing 500 marine animals from at least 525 species. The aquarium also supports active research and conservation programs. (Today in Science History)
20 October 2004...Typhoon Tokage became the tenth typhoon to strike Japan that year. Rain accompanying this typhoon triggered flash floods that washed away entire hillsides, killing 55 people and leaving at least 24 people missing. (National Weather Service files)
21 October 1797...The USS Constitution was launched at the Charlestown Navy Yard in Boston, MA. The ship, nicknamed "Old Ironsides," is now the oldest commissioned ship in the U.S. Navy. (Naval Historical Center)
21 October 1580...Portuguese navigator Ferdinand Magellan on his famous circumnavigation voyage of the globe reached Cape Virgenes and the strait at the tip of South America that now bears his name. Only three ships entered the 373-mile long passage separating Tierra del Fuego (land of fire) and the continental mainland. Navigating the treacherous strait in 38 days, the expedition entered the South Pacific Ocean, which Magellan named "Mar Pacifico" for the relatively tranquil seas that he found. However, one ship had been wrecked and another deserted. (The History Channel)
21-26 October 1998...Hurricane Mitch, a category 5 hurricane (on the Saffir-Simpson Scale), developed as a tropical depression over the southwestern Caribbean Sea about 360 mi south of Kingston, Jamaica on the 21^st. It would intensify over the next few days to become the second deadliest Atlantic hurricane on record, on the 24^th. By the 26^th, Mitch finally dissipated after remaining a category 5 hurricane for 33 hours. Estimated rainfall totals of up to 75 in. caused devastating flooding and mudslides in Honduras and Nicaragua for days. Estimated death toll from this hurricane was more than 11,000, the worst since 1780. (The Weather Doctor) (Accord Weather Calendar)
22 October 1988...A "nor'easter" swept across the coast of New England. Winds gusted to 75 mph, and large waves and high tides caused extensive shoreline flooding. (The National Weather Summary) (Storm Data)
22 October 2005...Isla Mujeres, Mexico set the Northern Hemisphere's and Western Hemisphere's 24-hour rainfall record with 64.33 inches thanks to Hurricane Wilma. (National Weather Service files)