Weekly Ocean News

Weekly Ocean News

DATASTREME OCEAN WEEK SEVEN: 11-15 March 2013

Items of Interest:

Time change -- Daylight Saving Time went into effect this past Sunday morning for essentially the entire nation -- the exceptions include Arizona, Hawaii, Puerto Rico and about 18 counties in Indiana. These changes have been mandated by the U.S. Congress in the Energy Policy Act of 2005, which extended Daylight Saving Time across the nation, with the start on the second Sunday in March (10 March 2013) and end on the first Sunday in November (3 November 2013). In other words, following the old adage of "spring ahead, fall behind", you will need to turn your clocks ahead by one hour to conform with the local time observance. Most of Canada also observes Daylight Saving Time changes at the same time [National Research Council Canada].
What does this time change mean to you (other than later sunsets)? Contrary to a popular belief that has surfaced at times, the change from Standard to Daylight Saving Time does not add an extra hour of daylight to the day nor does it affect weather patterns. While the weather will not change because of the time change, the times when you will be able to obtain weather charts will now be one hour later. The reason is that the National Weather Service operates on "Z time" (variously called Greenwich Mean Time or Universal Coordinated Time) which does not observe Daylight Saving Time, and the charts are still produced and transmitted at the same Z time.
While many people want additional daylight after work, some health experts say that the change to Daylight Saving Time is hard on human health, as it affects the natural sleep cycle and circadian rhythms. Increases in heart attacks, traffic accidents and sleep disorders have been seen during the first several days after the time change. [CBS Philly]
A spectrum of storms seen on one satellite image -- A full-disc visible satellite image obtained from data collected by a sensor onboard the EUMETSAT (European Organisation for the Exploitation of Meteorological Satellites) geosynchronous satellite in late January shows three "storms" that are of different space and time scales. This image shows an example of relatively small and short-lived thunderstorms in addition to a large and long-lived tropical cyclone and a slightly larger extratropical cyclone. [NASA Earth Observatory] Some atmospheric and climate scientists believe that higher global temperatures not only have resulted in changes in climate but also have meant fewer, but stronger storms. [NASA Earth Observatory]
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 --- As meteorological autumn began in the Southern Hemisphere last week, tropical cyclone activity was limited to the western South Pacific Ocean basin. A tropical storm formed at the start of last week approximately 760 miles to the northwest of Noumea, New Caledonia. During the week, this tropical storm intensified to become Tropical Cyclone Sandra as it traveled toward the east then southeast. By Sunday (local time), Sandra had intensified to become a major category 3 tropical cyclone on the Saffir-Simpson Scale. Tropical Cyclone Sandra was expected to pass to the west of New Caledonia early this week, possibly as a category 4 tropical cyclone with maximum sustained surface winds in excess of 130 mph. The NASA Hurricane Page has additional information and satellite imagery on Tropical Cyclone Sandra.
During the previous week, Tropical Cyclone Rusty, a category 2 tropical cyclone, traveled south across the South Indian Ocean and made landfall along Western Australia's Pilbara coast to the east-northeast of Port Hedland. The heavy rain accompanying this tropical cyclone caused sediment to runoff the land and into the rivers flowing into the Indian Ocean. A natural color image from the MODIS sensor on NASA's Aqua satellite obtained over one week ago shows the sediment flowing out into the ocean. NASA Hurricane Page
NASA facility recovering following Hurricane Sandy -- Being located on a barrier island along the Virginia coast, NASA's Wallops Island Flight Facility experienced damage last October when Hurricane Sandy made landfall. Aerial images before and after Sandy show some of the damage caused by high waves and strong winds. The Wallops Island Flight Facility is one of the nation's oldest rocket launch sites. [NASA Hurricane Mission]
Monetary value of nation's commercial and recreational saltwater fishing tallied -- NOAA's Fisheries Service recently published the annual report Economics of the United States 2011 that in 2011 US commercial and recreational saltwater fishing generated more than $199 billion in sales and supported 1.7 million jobs in the national economy. [NOAA Fisheries]
Sperm whales studied closely with aerial drones -- Scientists from NOAA Fisheries, the Woods Hole Oceanographic Institution, the New England Aquarium and the New Zealand Whale and Dolphin Trust who are participating in the Sperm Whales of New Zealand Expedition have been using aerial drones to monitor the movements of sperm whales in the waters off New Zealand from a relatively close distance. The new technology employed by this expedition has enabled the safe, non-invasive methods for monitory the health and physiology of these large whales. [NOAA Fisheries Service]
Unknown Civil War sailors buried at Arlington National Cemetery -- On the 151st anniversary of the Civil War's Battle of Hampton Roads between the ironclads USS Monitor and the CSS Merrimac, the remains of two unknown sailors from the Monitor were laid to rest with full military honors at Arlington National Cemetery near Washington, DC. These remains were recovered in 2002 in the gun turret of the Monitor, which sank off Cape Hatteras, NC in a storm in late December 1862. [NOAA News]
Operational responsibilities of newest environmental satellite changes hands -- Recently, NOAA assumed full operational responsibility for the nation's newest environmental satellite, Suomi National Polar-orbiting Partnership (Suomi NPP) satellite, from NASA, the agency that launched this spacecraft in October 2011. Since then, tests on each of the sensors onboard this polar-orbiting satellite have been run by NASA engineers. Over time data collected by the instruments onboard Suomi NPP have been used by NOAA for a variety of applications, including advanced warning for severe weather events such as tornado outbreaks, heavy snowfall, hurricanes, heat waves, floods, and wildfires. Editor's note: The Suomi NPP satellite, a prototype for the next-generation of environmental satellites, was named for Verner Suomi, a meteorology professor at the University of Wisconsin-Madison, who was a pioneer in the development of satellite sensors for use in meteorological applications. EJH [NOAA News]
Tracking how coastline has changed over time -- NOAA's National Ocean Service recently unveiled its Historical Shoreline Survey Viewer, an online way for the public to access at least 7000 historical shoreline surveys that have been conducted by NOAA and its predecessor organizations dating back to 1841. [NOAA National Ocean Service]
West Coast Fishery Management Program appears to work -- The West Coast Groundfish Trawl Catch Share Program, which involves a through a collaboration of the Pacific States Marine Fisheries Commission, the Pacific Fishery Management Council, the West Coast states, and NOAA Fisheries, was put in place in 2011 in an attempt to create a more efficient and sustainable fishery in the Pacific waters along the West Coast. A recent report indicates that since implementation of this catch share program, overall discards for the entire groundfish fishery due to bycatch in 2011 had dropped to less than 5 percent, which helped overfished populations a better chance to rebuild. [NOAA Fisheries Service]
Deciphering a ship's Plimsoll line -- NOAA's National Ocean Service provides a tutorial as to how one can decipher the markings on the hull of a commercial cargo ship near its waterline amidships called the "Plimsoll line." This line, which is used to help prevent overloading of a ship, is named for Samuel Plimsoll (1824ā€“1898), a member of the British Parliament who was responsible for the widespread usage. [NOAA National Ocean Service]
Robotic sub explores subglacial lake in Antarctica -- A researcher from NASA's Jet Propulsion Laboratory has been using a small baseball-bat-size robotic submersible device to explore and make images of the lake floor of Antarctica's subglacial Lake Whillans as part of an international Antarctic expedition that is being conducted. This device, called the "Micro-Submersible Lake Exploration Device," is equipped with hydrological chemical sensors and a high-resolution imaging system. [NASA Jet Propulsion Laboratory]
Power of tsunamis revealed -- In research conducted at the University of Southern California, that some tsunamis that are created by earthquakes off certain coasts, such as Java and Japan, will be massive and devastating, as focusing could created as much as 50 percent deeper waves that do not diminish in height as they approach the shore. [University of Southern California News]
Fishers near marine protected areas can fare well -- .... Fisheries scientists at Washington State University and in Hawaii report that even though fishers near marine protected areas are forced to travel farther to catch fish, they can maintain their social and economic well-being. Their study involved a network of marine protected areas along the western coast of Hawaii's Big Island. [Washington State University News]
Creation of Antarctica's hidden fjords is studied -- A team of geoscientists from the University of Arizona and their colleagues have reconstructed the changes in the topography under Antarctica's two-mile thick ice sheet over the last 34 million years that started from a relatively flat landscape and evolved into a rugged alpine landscape that included glaciers, fjords and mountains. This reconstruction is important for modeling how the Antarctic ice sheet affects global climate and sea-level rise. [University of Arizona News]
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

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

Historical Events:

11 March 2002...The National Ice Center reported that satellite images indicated that an iceberg with an area larger than the state of Delaware had calved from the Thwaites Ice Tongue, a region of snow and glacial ice extending from the Antarctic mainland into the South Amundsen Sea (Accord's Weather Guide Calendar)
13-15 March 1952...The world's 5-day rainfall record was set when a tropical cyclone produced 151.73 inches rain at Cilos, Reunion Island in the Indian Ocean. The 73.62 inches that fell in a 24-hour period (15^th-16^th) set the world's 24-hour rainfall record. (Accord's Weather Calendar)
14 March 1891...The submarine Monarch laid telephone cable along the bottom of the English Channel to prepare for the first telephone links across the Channel.
14 March 1903...President Theodore Roosevelt issued an executive order making Pelican Island near Sebastian Florida a "preserve and breeding ground for native birds," including pelicans and herons, marking the birth of the National Wildlife Refuge System. (Wikipedia)
14 March 1918...The first US concrete seagoing ship was launched at Redwood City, CA. (Today in Science History)
15 March 1493...Christopher Columbus returned to Spain after his first voyage to the New World. (Wikipedia)
15 March 1778...Nootka Sound, Vancouver Island was discovered by Captain James Cook.
15 March 1946...For the first time, U.S. Coast Guard aircraft supplemented the work of the Coast Guard patrol vessels of the International Ice Patrol, scouting for ice and determining the limits of the ice fields from the air. (USCG Historian's Office)
15 March 1960...Key Largo Coral Reef Preserve in the Florida Keys was established as the nation's first underwater park. This preserve currently includes John Pennekamp Coral Reef State Park and the adjacent Florida Keys National Marine Sanctuary.
16 March 1521...Portuguese navigator Ferdinand Magellan reached the Philippines. He was killed the next month by natives.
16 March 1834...The HMS Beagle anchored at Berkeley Sound, Falkland Islands.
16 March 1889...A war between the U.S. and Germany was likely averted as a hurricane sank all three U.S. and three German warships in the harbor at Apia, Samoa. Joint U.S., German and Samoan rescue cooperation led to the Treaty of Berlin (1889) that later settled the dispute. (Accord's Weather Calendar)
17 March 1891...The British steamer SS Utopia sank off the coast of Gibraltar, killing 574 people. (Wikipedia)
17 March 1898...The USS Holland, the first practical submarine, was demonstrated by John Holland as it made its first dive in the waters off Staten Island, New York for one hour and 40 minutes. (Naval Historical Center)
17 March 1941...USCGC Cayuga left Boston with the South Greenland Survey Expedition onboard to locate airfields, seaplane bases, radio and meteorological stations, and aids to navigation in Greenland. (USCG Historian's Office)
17 March 1959...The submarine USS Skate (SSN-578) surfaced at the North Pole. (Naval Historical Center)