Weekly Ocean News

WEEK SEVEN: 15-19 October 2012

For Your Information

• Opportunity for Teachers: The National Ocean and Atmospheric Administration's (NOAA) Teacher at Sea 2013 Field Season program is now accepting applications until the end of business on 31 October 2012. Gain your "sea legs" and first-hand experience in one-week to one-month voyages. For more information, or to apply, see http://teacheratsea.noaa.gov.
• Celebrate Earth Science Week 2012 -- The National Oceanic and Atmospheric Administration, including the National Weather Service, along with NASA, the US Geological Survey and several professional scientific organizations such as the American Geological Institute have recognized next week (14-20 October 2012) as Earth Science Week 2012 to help the public gain a better understanding and appreciation for the earth sciences and to encourage stewardship of the Earth. This year's theme for the 15th annual Earth Science Week is " Discovering Careers in the Earth Sciences", designed to "engage young people and the public in learning how geoscientists gather and interpret data about the Earth and other planets." [American Geological Institute]
  Starting on the 14th, students will be invited to connect with NASA Earth explores on virtual trips to Antarctica, the Peruvian Amazon, the mangrove forests of Africa and many other places around the world to inspire them to pursue science, technology, engineering and math (STEM) careers. [NASA GSFC]
• 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.

• Eye on the tropics -- Several tropical cyclones were found across the North Atlantic and North Pacific Oceans during the last week, while the first tropical cyclone of the season developed in the Southern Hemisphere:
• In the North Atlantic basin, Tropical Storm Patty formed late in the week from a tropical depression over the waters northeast of the Bahamas. Patty, the sixteenth named tropical cyclone of the 2012 Atlantic hurricane season, was relatively short lived as it weakened to a tropical depression late Friday afternoon after being a minimal tropical storm for less than 24 hours. Patty traveled to the southwest and then north. See the NASA Hurricane Page for additional information and satellite imagery on Tropical Storm Patty.
  Tropical Storm Rafel formed late last Friday afternoon from an area of disturbed tropical weather over the eastern Caribbean Sea that the National Hurricane Center identified as "System 98-L." Over the weekend, Rafel intensified as it moved northward across the western North Atlantic. Rafel could intensify to a minimal hurricane by early Monday evening. The NASA Hurricane Page had brief information on System 98-L and a satellite image before the system intensified to become Tropical Storm Rafel.
• In the eastern North Pacific basin, Tropical Storm Paul, the sixteenth named tropical cyclone of the 2012 eastern Pacific season formed early this past weekend well off the western coast of Mexico. Tropical Storm Paul intensified slowly as it initially traveled toward the west, before curving toward the northwest. Paul could become a minimal hurricane early Monday as it was expected to travel to the north toward the central sections of the coast of Mexico's Baja California Peninsula.
  
• In the western North Pacific basin, the 22nd tropical cyclone of 2012 in that basin formed early last week from a tropical depression approximately 600 miles southeast of Okinawa, Japan. This system intensified into Typhoon Prapiroon as it traveled westward before turning toward the north and then to the northeast late last week. By late week, Typhoon Prapiroon had intensified to briefly become a major category 3 typhoon on the Saffir-Simpson Scale, with maximum sustained surface winds of at least 110 mph with gusts over 130 mph. Sea wave heights reached over 40 feet. This system weakened to a category 1 typhoon over the weekend as it headed north toward southern Japan. Additional information on Typhoon Prapiroon along with satellite imagery is available on the NASA Hurricane Page.
  Over the weekend, Tropical Storm 23-W, also identified as Tropical Storm Maria, formed near the Northern Mariana Islands. This tropical storm was moving toward the northwest.
  
• In the South Indian Ocean basin of the Southern Hemisphere, the first named tropical cyclone of the new season in this basin formed near the end of last week to the west-southwest of Diego Garcia. This tropical cyclone, originally designated Tropical Cyclone 1S, was later identified as Cyclone Anais as it tracked toward the southwest and intensified to a category three cyclone on the Saffir-Simpson Scale over the weekend. The NASA Hurricane Page has additional information and a satellite image Tropical Cyclone 1S.
• Sea ice around Antarctica expands to record size -- The National Snow and Ice Center recently reported that analysis of satellite images obtained from the Special Sensor Microwave/Imagers onboard the Defense Meteorological Satellite Program (DMSP) satellites shows that in late September 2012 the sea ice surrounding Antarctica grew to its greatest annual winter maximum extent since satellite surveillance began in 1979. Note that this record expanse of Antarctic sea ice occurred approximately two weeks after the sea ice covering the Arctic Ocean had shrunk to the smallest annual summer extent in the satellite record. Sea ice scientists at NASA's Goddard Space Flight Center claim that changes in the atmospheric circulation has contributed to the increased Antarctic sea ice. [NASA Earth Observatory]
• Celebrating the 40th anniversary of the nation's marine sanctuaries -- A NOAA Ocean Today video was prepared that helps celebrate the 40th anniversary of the signing of the National Marine Sanctuaries Act, which created the nation's national marine sanctuary system. [National Ocean Service] Attention is also directed to the montage that highlights the top 40 accomplishments attained by the National Marine Sanctuaries during their 40 years of existence. [National Marine Sanctuaries]
• Nation's weather satellites have helped save lives for 30 years -- Last week marked the 30th anniversary of the first marine rescue that was assisted by one of NOAA's orbiting satellites. On this date, a distress signal was detected by a satellite, which allowed the US Coast Guard to rescue three passengers from a sinking catamaran sailboat off the New England coast . While the fleet of NOAA satellites has a main mission for observing the Earth's environment, they are equipped with technology to detect and locate distress signals from emergency beacons onboard aircraft and ships and from handheld personal locator beacons. Since 1982, NOAA satellites have been part of the Search and Rescue Satellite-Aided Tracking system (Cospas-SARSAT), an international program responsible for the rescue of more than 30,000 people worldwide and nearly 7000 in the United States. [NOAA News]
• New products can measure heat available for hurricanes -- Researchers at the University of Miami have developed a new Ocean Heat Content product suite that is now being implemented at NOAA to predict hurricane intensification based upon the thermal energy contained in the near surface waters of the Atlantic Ocean. This product used data obtained from NOAA National Oceanographic Data Center's "World Ocean Atlas" along with sea surface height measurements from the NOAA/NASA Jason satellites. [NOAA Environmental Visualization Lab]
• Aerial drones provide new perspective for marine research -- A team of scientists from NOAA's Southwest Fishery Science Center will use a robotic aerial drone armed with a high-resolution digital camera to conduct marine mammal research on an ice covered island near the end of the Antarctic Peninsula. [NOAA Fisheries Service]
• New manual provides tips for combating invasive lionfish -- NOAA officials recently released a new manual entitled "Invasive Lionfish: A Guide to Control and Management" produced by scientists from NOAA's National Centers for Coastal Ocean Science and their colleagues that create guidelines for coastal managers to control the spread of invasive lionfish. These lionfish, now found in the nation's coastal waters from the Carolinas to Texas and across the Caribbean, are taking food and habitat from those native fish that are important to the local ecology and economy. [NOAA News]
• Increased carbon dioxide levels cause glaciers to crack -- Researchers at the Massachusetts Institute for Technology have found that the strength and fracture toughness of ice decrease significantly as the concentration of carbon dioxide molecules increases. They claim that their finding indicates that with higher atmospheric carbon dioxide levels, ice caps and glaciers would become more vulnerable to cracking and splitting. [Institute of Physics]
• Backup weather satellite serves as worthy replacement -- NOAA's GOES-13 satellite, identified as GOES-East since April 2010, began experiencing sensor problems in mid-September. This satellite was identified as GOES-East because it was the nation's environmental satellite in geosynchronous orbit that monitored the weather across eastern North America. Within a day, NOAA engineers were able to replace GOES-13 with GOES-14, a spare satellite that was a spare satellite since it was launched in June 2009. [NASA Earth Observatory]
• Astronauts connect with oceanographers -- An physical oceanographer from NASA and colleagues who were out at sea on the Research Vessel Knorr recently communicated in a long-distance telephone call with the astronauts orbiting onboard the International Space Station. The oceanographers had nearly completed a six-week SPURS (Salinity Processes in the Upper ocean Regional Study) cruise designed to obtain a detailed, 3-D picture of how salt content fluctuates in the ocean's upper layers and how these variations are related to shifts in rainfall patterns around the planet. The data collected from this cruise was also meant to help calibrate the salinity measurements collected by the orbiting NASA's Aquarius instrument. [NASA Headquarters]
• Summertime wind shift in Arctic could affect sea ice loss and weather across North America and Europe -- A research team from NOAA's Pacific Marine Environmental Laboratory reported that changing upper air wind patterns over the Arctic Basin between 2007 and 2012 may affect weather across North America and Europe because the shift in winds in summer appear to be linked to the recent dramatic loss in Arctic sea ice. The prevailing winds across the basin shifted from a west to east flow to a more undulating north-south wavelike pattern, which permitted warmer air to be transported north to the Arctic during summer, while more cold air was brought southward to mid-latitudes over North America and Europe. [NOAA News]
• Small fish appears to play big role in coastal carbon cycle -- Researchers from Rutgers University and the Virginia Institute of Marine Science report that fish fecal pellet data collected on an oceanographic expedition along the California coast indicate small forage fish, such as anchovies, appear to play an important role in the "biological pump" in which marine life transports carbon dioxide from the atmosphere and surface ocean into the deep sea. [Virginia Institute of Marine Science]
• Decrease in frequency of Hawaii's northeast trade winds documented -- Scientists at the University of Hawaii's School of Ocean and Earth Science and Technology analyzed 37 years of wind data (speed and direction) from Honolulu's International Airport along with area sea level pressure data and found a reduction in the frequency of days with northeast trade winds, but with a corresponding increase in easterly trade wind days over this length of record. The Hawaii State Climatologist claims that reduction in the frequency of humid trade winds from the northeast appear to cause a change in Hawaii's climate, including more frequent drought across the Aloha State. [ School of Ocean and Earth Science and Technology, University of Hawaii at Manoa]
• An All-Hazards Monitor -- This Web portal provides the user information from NOAA on current environmental events that may pose as hazards such as tropical weather, drought, floods, marine weather, tsunamis, rip currents, Harmful Algal Blooms (HABs) and coral bleaching. [NOAAWatch]
• Global and US Hazards/Climate Extremes -- A review and analysis of the global impacts of various weather-related events, to include drought, floods and storms during the current month. [NCDC]
• Earthweek -- Diary of the Planet [earthweek.com] Requires Adobe Acrobat Reader.

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 pages 156-157 in 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).

Go to the University of Delaware's Seiche Calculator at http://www.coastal.udel.edu/faculty/rad/seiche.html. Set the "Modal Number" to 1 and then press "Calculate" for a graphical simulation of a seiche in an enclosed basin.

Partially enclosed basins usually have a node located at the mouth (rather than near the center) and an antinode at the landward end. Go to the Seiche Calculator, set the "Modal Number" to 0.5 and then press "Calculate" for a simulation of a seiche in a basin open to the right. Furthermore, some basins are complex and have multiple nodes and antinodes; these can be simulated on the Seiche Calculator by selecting different values of "Modal Number" greater than one.

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. Using the Seiche Calculator, you may wish to experiment with different basin lengths and depths. Conversely, one can determine the average depth of a lake by determining the period of the seiche and the length of the lake.

Concept of the Week: Questions

1. In an enclosed basin the node of a seiche is located [(at either end) (near the center)] of the basin.
2. The natural period of a seiche [(depends on) (is independent of)] the size of an enclosed basin.

Historical Events:

• 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)
• 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)

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Prepared by DS Ocean Central Staff and Edward J. Hopkins, Ph.D., email hopkins@meteor.wisc.edu
© Copyright, 2012, The American Meteorological Society.