Weekly Ocean News

WEEKLY OCEAN NEWS

WEEK SIX: 8-12 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.
Biomixing in ocean motion -- If you would like information on recent findings that indicate marine organisms contribute to motion in the ocean, please read this week's Supplemental Information…In Greater Depth.
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]

Ocean in the News

Eye on the tropics -- Several tropical cyclones were found across the North Atlantic and North Pacific Oceans during the last week:

In the North Atlantic basin, Hurricane Nadine, a category 1 hurricane on the Saffir-Simpson Scale completed another loop near the Azores at the start of the week. This long-lived tropical cyclone had traversed the tropical and subtropical North Atlantic in a somewhat erratic fashion for approximately three weeks, weakening to become a tropical storm and a remnant subtropical system before re-intensifying to a hurricane at the end of the previous week. Early last week Nadine weakened again to a tropical storm and by late last week, Tropical Storm Nadine had lost its structure as it merged with a midlatitude frontal system that was moving across the North Atlantic. See the NASA Hurricane Page for additional information and satellite imagery on Hurricane Nadine. Nadine will be remembered as one of the longest living tropical cyclones in either the North Atlantic or North Pacific Basins. [USA Today]
Tropical Storm Oscar formed from a tropical depression at near the middle of last week over the central tropical Atlantic to the west-northwest of the Cape Verde Islands. By the weekend Tropical Storm Oscar also was assimilated into a cold front after traveling to the north and northeast near the end of the week. For more information and satellite imagery on Tropical Storm Oscar, consult the NASA Hurricane Page.

In the eastern North Pacific basin, Tropical Storm Olivia, the fifteenth named tropical cyclone of the 2012 season in that basin formed over the weekend from a tropical depression that was well off the coast of Mexico. Movement was initially toward the west, then toward the north over the weekend. Olivia was expected to turn toward the west on Monday and eventually dissipate. .
In the western North Pacific basin, Tropical Storm Maliksi formed from a tropical depression located near Guam at the start of last week. This tropical storm traveled in a generally northward direction and brushed the Tohoku and Hokkaido prefectures of northern Japan by midweek

NASA Hurricane Page

"Coral hotspots discovered in deepwater canyons off Northeast Atlantic coast -- Researchers from NOAA's National Fisheries Service participating on an exploration of the North Atlantic waters off the Northeastern United States onboard the NOAA ship Henry B. Bigelow have discovered "coral hotspots" in submarine canyons off New Jersey and Cape Cod, MA. These hotspots likely serve as important deep sea habitat for various marine life. [NOAA Habitat Conservation]
Federal protection of great white shark in the northeastern Pacific is deemed warranted -- Recently, NOAA Fisheries published a notice in the Federal Register that indicates the northeastern Pacific Ocean population of great white shark may warrant listing under the Endangered Species Act. This finding is based upon two petitions received this summer. [NOAA Fisheries Service]
Approval given to expanded Louisiana Coastal Zone Boundary -- NOAA's Office of Ocean and Coastal Resource Management recently approved a new inland boundary for the Louisiana Coastal Management Program that would expand the Coastal Zone Boundary by approximately 12.6 percent. [National Ocean Service]
Thinning of younger Arctic sea ice detected -- Scientists from the National Snow and Ice Data Center and their colleagues report that the year-round or multi-year Arctic sea ice at the end of the summer melt season in mid September 2012 was thinner and younger than in previous seasons. In addition, the amount of smallest extent of Arctic sea ice since satellite surveillance began in 1979. [NOAA ClimateWatch Magazine]
What's up with the potential El Niño? -- Bob Henson from the National Center for Atmospheric Research (NCAR) considers whether the El Niño event that was predicted to develop this fall would actually develop into a moderate event or remain relatively weak. While the waters of the eastern tropical Pacific did warm slightly this summer as a sign of an upcoming El Niño event, the pattern of sea surface temperatures across the region is now sending mixed signals. This new development will have a somewhat unclear effect on the weather pattern across North America during this winter [NCAR/UCAR AtmosNews] El Niño events differ distinctly from La Niña events. A La Niña event had occurred last year. Maps have been prepared that show the difference from average December-February temperature and precipitation across the nation averaged over 22 El Niño and 19 La Niña episodes that have occurred in the past 60 years. [NOAA ClimateWatch Magazine]
Southern Hemisphere appears to becoming drier -- Researchers at Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) report that the Southern Hemisphere has becoming drier especially during the austral fall season (April-May) due to a decline in rainfall during this season across southeastern Australia, as well as over the Southern Ocean to the south of Africa. This rainfall decline appears to be an expansion of the subtropical dry zone and a poleward (or southward) shift in the major storm tracks across the region. [Explore CSIRO]
Manatees indicator of quality of health in marine ecosystems -- A team of scientists from George Mason University, the University of California-Davis, the US Geological Survey and Sea to Shore Alliance claim their research on manatees in the waters off Belize indicates manatees appear to be "sentinel species," serving as indicators of their environment that could potentially provide early warning of changes to the overall health of marine ecosystems. [George Mason University News]

Pinellas Beaches Patch

Editor's note:

EJH

Clam shells used to find clues to Atlantic's climate history -- Researchers from Iowa State University have collected clam shells from the waters of the Gulf of Maine and analyzed the annual shell increments or bands on these shells using geochemical testing and radiocarbon techniques to determine the temperature, circulation patterns and the growing conditions in the North Atlantic over the last thousand years. Changes in water temperatures during the Medieval Climate Anomaly (AD 950 to 1250) and the Little Ice Age (AD 1550 to 1850) were documented. [Iowa State University News Service]
History of the sea found from the "chemical memory" of seawater -- A chemist from Germany's Alfred Wegener Institute for Polar and Marine Research and his colleagues have been using mass spectrometers and other new techniques to analyze the biomolecular tracks of marine life dissolved in seawater as a means to study the past history of the oceans. The scientists are attempting to reconstruct the climate history and determine the global amount of carbon stored in the oceans as dissolved organic matter. [Alfred Wegener Institute for Polar and Marine Research]
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: Abyssal Storms

Until recently, ocean scientists thought of the deep ocean abyss as a dark and cold, but serene place where small particles rained gently onto the ocean floor. However, instruments lowered to the sea floor to measure ocean motion or currents and resulting mobilization of bottom sediments detected a much more active environment. Scientists found that bottom currents and abyssal storms occasionally scour the ocean bottom, generating moving clouds of suspended sediment. A surface current of 5 knots (250 cm/sec) is considered relatively strong. A bottom current of 1 knot (50 cm/sec) is ripping. Although this may be called an abyssal storm, the water motion pales by comparison to wind speeds in atmospheric storms.

Abyssal currents and storms apparently derive their energy from surface ocean currents. Wind-driven surface ocean currents flow about the margins of the ocean basins as gyres centered near 30 degrees latitude. (Refer to Figure 6.6, page 152, in your textbook.) Viewed from above, these subtropical gyres rotate clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere. For reasons given in Chapter 6 of your textbook and this week's Supplemental Information, surface currents flow faster, are narrower, and extend to greater depths on the western arm of the gyres. These are known as western boundary currents and include, for example, the Gulf Stream of the North Atlantic basin. Abyssal currents are also most vigorous on the western side of the ocean basins, moving along the base of the continental rise, which is on the order of several kilometers deep.

Abyssal storms may be linked to or may actually be eddies (rings) that occasionally break off from the main current of the Gulf Stream (and other western boundary currents). During an abyssal storm, the eddy or ring may actually reach to the bottom of the ocean where the velocity of a bottom current increases ten-fold to about 1.5 km (1 mi) per hr. While that is an unimpressive wind speed, water is much denser than air so that its erosive and sediment-transport capacity is significant even at 1.5 km per hr. At this higher speed, the suspended sediment load in the bottom current increases by a factor of ten. Abyssal storms scour the sea floor leaving behind long furrows in the sediment. After a few days to a few weeks, the current weakens or the eddy (ring) is reabsorbed into the main surface circulation and the suspended load settles to the ocean floor. In this way, abyssal storms can transport tons of sediment long distances, disrupting the orderly sequence of layers of deep-sea sediments. Scientists must take this disruption into account when interpreting the environmental significance of deep-sea sediment cores.

Concept of the Week: Questions

In the subtropical ocean gyres, boundary currents flow faster on the [(western)(eastern)] side of an ocean basin.
Currents in an abyssal storm erode, transport, and redeposit sediments that have accumulated on the [(continental shelf)(deep ocean bottom)].

Historical Events

9 October 1873...LT Charles Belknap called a meeting at the Naval Academy to establish the U.S. Naval Institute for the purpose of disseminating scientific and professional knowledge throughout the U.S. Navy. (Navy Historical Center)
9 October 1967...A cyclone of relatively small dimension with a surface width of only 31 miles, hit India's coast at Orissa and moved to the northeast along the coast for 75 miles. As many as 1000 people and 50,000 head of cattle died. A surge in the storm's wake penetrated 16 miles inland. (Accord Weather Guide Calendar)
10 October 1845...Naval School, renamed the U.S. Naval Academy, opened in Annapolis, MD with 50 midshipmen students and seven faculty. (Navy Historical Center)
10 October 1861...Fridtjof Nansen, the Norwegian explorer, oceanographer, statesman, and humanitarian was born. Nansen led a number of expeditions to the Arctic (1888, 1893, 1895-96) and oceanographic expeditions in the North Atlantic (1900, 1910-14). He wrote The Oceanography of the North Polar Basin (1902). For his relief work after World War I, he was awarded the Nobel Prize for Peace in 1922. (Today in Science History)
10 October 1913...President Woodrow Wilson with the aid of a telegraph signal sent from Washington, DC triggered the demolition of the Gamboa Dike, allowing water to fill the Culebra Cut and create Lake Gatun, at 85 ft above sea level, the largest man-made lake at that time. This act signaled the completion of construction of the Panama Canal, which would eventually open to ship traffic between the Atlantic and Pacific Oceans on 14 August 1914. (Wikipedia, Today in Science History)
11 October 1737...A deadly cyclone and storm surge of 42 ft raced up the Hooghly River in India and through the city of Calcutta destroying an estimated 40,000 boats and drowning as many as 300,000 people. (The Weather Doctor)
11 October 1846...A very intense hurricane caused great destruction in the Florida Keys. Key West was virtually destroyed with 5 feet of water reported in the city. Fort Taylor was reduced to ruins. (Intellicast)
11 October 1897...Property saved at Cape Hatteras, NC. During a severe storm, the surf threatened to wash away a fish house, with valuable nets and other gear. Surfmen saved the property and took it to a place of safety. They also assisted a lighthouse keeper by removing lenses from the beacon to a secure place. The lighthouse was in danger of being washed away by the sea. (US Coast Guard Historian's Office)
12 October 1492...Italian explorer Christopher Columbus sighted and landed on an island (possibly Watling Island) in the Bahamas during his travels westward across the Atlantic Ocean in search of an ocean route to eastern Asia. Apparently he underestimated the size of the world and assumed that he had reached East Asia after setting sail with three ships from Palos, Spain on 3 August 1492. During this expedition, which was the first known European expedition to the Americas since the 10^th century Viking colonies in Newfoundland, he sighted Cuba and landed on Hispaniola. (The History Channel)
12 October 1886...A hurricane made landfall between Sabine Pass, TX and Johnson's Bayou, LA. Waves were said to be as high as 2-story buildings. The surge extended 20 mi inland, with 150 people killed. Survivors clung to trees or floated on mattresses. Only two of 100 homes in Sabine Pass were reparable. (Accord Weather Calendar)
12 October 1954...Hurricane Hazel pounded Haiti and the island of Hispaniola with winds of 125 mph. Many villages were reported totally destroyed and more than 1000 Haitians died. (The Weather Doctor)
12 October 1965...End of Project Sealab II where teams of naval divers and scientists spent 15 days in Sealab moored 205 feet below surface near La Jolla, CA. (Navy Historical Center)
12 October 1979...The lowest observed sea-level barometric pressure (870 millibars or 25.69 inches of mercury) was recorded near Guam in the western Pacific Ocean at the center of Typhoon Tip. (The Weather Doctor)
13 October 1775...Birthday of U.S. Navy. The Continental Congress established the Continental Navy, later the U.S. Navy. (Naval Historical Center)
13 October 1884...The longitude that passes through the principal Transit Instrument at the Observatory in Greenwich, England was selected as the single universal meridian at the International Meridian Conference held in Washington, DC. A universal day was also selected. (Today in Science History)