Weekly Ocean News

WEEKLY OCEAN NEWS

WEEK FOUR: 24-28 September 2012

For Your Information

Reconstructing past oceanic conditions from marine sediment cores -- If you would like information on how scientists can reconstruct past environmental conditions in the oceans from the analysis of the physical, chemical and geological data in deep-sea sediment cores, please read this week's Supplemental Information…In Greater Depth.
Watch live video of seafloor exploration of deep-sea volcanoes --The public using a computer or a mobile device can view live video and virtually join a NOAA-led team of 35 scientists on Monday and Tuesday of this week as they explore seafloor volcanoes in the Western Pacific's Lau Basin, centered between Samoa, Fiji and Tonga [NOAA News]
National Climatic Data Center releases accomplishments report for 2011 -- NOAA's National Climatic Data Center recently released its "2011 Annual Accomplishments Report" describing the accomplishments made in 2012 by this Center that archives weather and climate data for not only the nation but for many other countries. Two major accomplishments include the release of the new 1981-2010 climate normals for the nation and the creation of a new version of the Global Historical Climatology Network-Monthly dataset. [NCDC News]
Environmental literacy grants to support K-12 science education and stewardship projects -- NOAA officials recently announced that $4.5 million in grants from the NOAA Office of Education's Environmental Literacy Grants Program have been awarded to support six unique projects designed to enhance the nation's science education activities in classrooms, aquariums, museums and other institutions. [NOAA News]

Ocean in the News

Eye on the tropics -- While the tropical waters in the ocean basins of the Northern Hemisphere were relatively warm, only a few tropical cyclones were found across these basins during the last week:

In the North Atlantic basin, Tropical Storm Nadine traveled to the northeast toward the Azores early last week, but turning to the east and then southeast before reaching the islands. By late in the week, this former hurricane had turned toward the southeast and was classified a post tropical cyclone or remnant low. However at the end of the weekend, this system had reorganized and became Tropical Storm Nadine again. This newly reformed tropical storm was expected to travel westward. Additional information on Tropical Storm Nadine along with satellite imagery can be found on the NASA Hurricane Page.

In the eastern North Pacific basin, Tropical Storm Kristy weakened to become a tropical depression and then to a remnant low pressure area off the coast of Mexico's Baja California Peninsula by the beginning of last week. Satellite imagery and additional information on Tropical Storm Kristy appears on the NASA Hurricane Page.
Tropical Storm Lane became the eighth hurricane of the 2012 eastern Pacific hurricane season early last week as it moved well off the western coast of Mexico. However, Lane remained a minimal category one hurricane for little more than 24 hours. By midweek, Lane weakened to a tropical storm and then a depression. Satellite images and additional information on former Hurricane Lane can be found on the NASA Hurricane Page.
Near the end of last week, a tropical storm formed off the southwestern coast of Mexico. Representing the thirteenth named tropical cyclone of the 2012 season, Tropical Storm Miriam, continued to intensify as it traveled to the northwest along the Mexican coast. Miriam was expected to become a hurricane by early this new week.
In the western North Pacific basin, former Super Typhoon Sanba made landfall along the southern coast of the Korean Peninsula at the start of last week. The NASA Hurricane Page has satellite images and further information on Super Typhoon Sanba.
Late in the week, another tropical storm formed from a tropical depression that had developed earlier over the Philippine Sea to the east of the Philippines. This tropical storm, which was named Jelawat, became a typhoon when maximum sustained wind speeds exceeded 74 mph early Sunday (local time). By late in the day, Typhoon Jelawat had intensified to a super typhoon as it traveled northward well to the east of the Philippines. See the NASA Hurricane Page for more information on Typhoon Jelawat.

Summer's Arctic sea ice extent reaches a record minimum -- Researchers at the University of Colorado at Boulder's National Snow and Ice Data Center report that as of mid September (or more precisely, on 18 September 2012), the extent of Arctic sea ice appears to have reached a minimum for the 2012 summer season. According to the researchers, last week's areal extent of the Arctic sea ice represents the smallest since routine satellite surveillance commenced in 1979. [University of Colorado] Data and graphs are available. [National Snow and Ice Data Center] Scientists at NASA's Goddard Space Flight Center have also produced a variety of graphics including an animation of how winds from a powerful storm have affected the Arctic Ice during this past August. [NASA's Earth Science News Team]
Review of August and boreal summer 2011 global temperatures -- Preliminary data analyzed by scientists at NOAA's National Climatic Data Center indicated that the global combined land and ocean average surface temperature for August 2011 was nearly one Fahrenheit degree above the 20th-century average for the month. Last month's global average temperature tied for the eighth highest August monthly temperature since global temperature records began in 1880. When considered separately, the monthly temperature of the land surface for this recently concluded month was the second highest August temperature on record, while the ocean temperature for the month was the twelfth highest. The researchers also noted that the global land and ocean average temperature for the three-months of June, July and August (meteorological summer in the Northern Hemisphere) was the seventh highest for that three-month period since 1880. [NOAA News]
Grants awarded to predict ocean acidification's effects on commercial fisheries -- NOAA recently announced that grants totaling nearly $1.6 million have been awarded to Woods Hole Oceanographic Institution, The State University of New York at Stony Brook and the University of Washington to conduct multi-year research projects to examine the effects of ocean acidification upon fisheries and the coastal economies that depend these fisheries. [NOAA News]
National seafood catches in 2011 reach 17-year high -- The NOAA's Fisheries Service recently released their annual report entitled "Fisheries of the United States 2011." According to this report, US commercial fishermen landed a 17-year high in the pounds of fish and shellfish in 2011, apparently due to the rebuilding of fish populations and the increased values of landings. [NOAA News]
Mathematicians show how shallow waves may explain tsunami power -- Applied mathematicians at the University of Colorado-Boulder have discovered that their observations of the interactions of waves in shallow water bodies can be used to explain why some tsunamis can build and create great havoc. The resulting X- and Y-shaped waves produced by these interactions can be predicted by mathematical equations. [University of Colorado, Boulder]
Unusual symbiosis in marine microorganisms discovered -- Researchers from the University of California-Santa Cruz and collaborators from Hawaii, Germany and France have discovered that single-cell algae and nitrogen-fixing bacteria and a symbiotic relationship that helps fertilize the oceans by extracting atmospheric nitrogen and "fixing" the nitrogen into a form that other organisms can utilize. [National Science Foundation]
Overgrown algae can contribute to coral reef decline -- Researchers at Oregon State University claim that the growth of "macro algae," or large algal species, due to overfishing and nitrate pollution can become sufficiently large to essentially smother coral reefs. [Oregon State University 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: Variations in Marine Sediment Thickness

Sediments are particles of organic or inorganic origin that accumulate in loose form in depositional environments such as lake or ocean bottoms. Marine sediments, the central focus of this week's investigations, have a variety of sources and exhibit a wide range of composition, size, and shape. Marine sediments settle to the ocean floor as unconsolidated accumulations but ultimately may be converted to solid sedimentary rock via compaction and cementation. The pattern of variations in marine sediment thickness on the ocean floor confirms some basic understandings regarding marine geological processes.

Go to the DataStreme Ocean Website and under "Geological," click on "Sediment Thickness." This map of marine sediment thickness in the ocean basins was compiled by the National Geophysical Data Center (NGDC), Marine Geology and Geophysics Division primarily based on existing maps, ocean drilling, and seismic reflection profiles. Sediment thickness is color-coded in meters from violet (thinnest) to red (thickest). Many factors account for the variation in the thickness of marine sediment deposits including type and location of sediment sources, sediment transport mechanisms, and the age of the underlying crust.

According to the map, sediment thickness generally increases with distance from near the central portion of an ocean basin to the continental margin. This pattern may be explained by the principal sediment source and/or the age of the underlying crust. Rivers and streams that empty into the ocean slow and diverge, releasing the bulk of their suspended sediment load in coastal environments (e.g., bays, estuaries, deltas) and onto the continental shelf. Ocean currents transport sediment along the coast. In some areas of the continental shelf, massive amounts of sediment accumulate, become unstable, and flow down the continental slope to the base of the continental rise and beyond. However, only the finer fraction of river-borne sediment is swept into the deep ocean waters. Thickening of marine sediments in the direction of the continental margin may also reflect the aging of oceanic crust with distance away from divergent (spreading) plate boundaries where new oceanic crust forms. The older the crust the longer is the period that sediment rains down on the ocean bottom and the thicker is the blanket of accumulated sediment.

The map indicates that the thickness of marine sediment deposits is greater in the continental margin along the Atlantic coast of North America than along the Pacific coast. The Atlantic coast of North America is a passive margin; that is, the continental margin is not affected significantly by tectonic processes (no plate boundary) and the principal geological processes consist of sedimentation along with erosion by ocean waves and currents. In fact, passive margins and relatively thick marine sediment deposits occur on both sides of the Atlantic. (Passive margins also occur around the Arctic Ocean and surrounding Antarctica.) On the other hand, the Pacific coast of North America is an active margin; that is, the continental margin is associated with plate boundaries and is subject to deformation by tectonic stresses. Active continental margins are relatively narrow so that sediment delivered to the coast by rivers and streams flows directly into deeper water or trenches—preventing thick accumulations of marine sediments from building in the continental margin.

Concept of the Week: Questions

The thickness of marine sediment deposits is greater in the [(continental margins)(deep-ocean basins)].
The thickness of marine sediment deposits generally is greater in [(active)(passive)]continental margins.

Historical Events

24 September 1493...Christopher Columbus set sail with 17 ships on his second expedition to the New World, reaching the Lesser Antilles, the Virgin Islands, Puerto Rico and Hispaniola before returning to Europe in March 1496. (Wikipedia)
25 September 1513...Vasco Núñez de Balboa, a Spanish conquistador-explorer, crossed the isthmus of Panama and reached the Pacific Ocean, which he christened Mar del Sur (South Sea), claiming the ocean and all adjacent lands for Spain. (Wikipedia)
25 September 1939...A West Coast hurricane moved onshore south of Los Angeles bringing unprecedented rains along the southern coast of California. Nearly 5.5 in. of rain drenched Los Angeles during a 24-hr period. The hurricane caused $2 million in damage, mostly to structures along the coast and to crops, and claimed 45 lives at sea. "El Cordonazo" produced 5.66 in. of rain at Los Angeles and 11.6 in. of rain at Mount Wilson, both records for the month of September. (David Ludlum) (The Weather Channel)
25 September 1956...The world's first transatlantic telephone cable system began operating (Clarenville, Newfoundland to Oban, Scotland). Previous cables had been limited to telegraph transmissions. (Today in Science History)
26 September 1580...English seaman Francis Drake returned to Plymouth, England, in the Golden Hind, becoming the first British navigator to circumnavigate the globe. He had commenced his voyage around the world on 13 December 1577 with five ships, but returned with only one ship. During his voyage in the Pacific Ocean, he paused near San Francisco Bay and then traveled as far north as present-day Washington State. He brought back valuable information about the world's ocean to Queen Elizabeth I. (The History Channel)
26-27 September 1959...Typhoon Vera ravaged Honshu, Japan, the nation's largest island, leaving over 5000 dead, more than 40,000 injured, 1.5 million homeless and 40,000 homes destroyed. It was Japan's greatest storm disaster. (The Weather Doctor)
27 September 1854...After colliding with the French ship SS Vesta in dense fog, the American Collins Line steamship Arctic sank with more than 300 people on board near Cape Race, Newfoundland, marking the first great disaster in the Atlantic Ocean. (Wikipedia)
27 September 1922...Report on observations of experiments with short wave radio at the Naval Aircraft Radio Laboratory in Anacostia, DC started US Navy development of radar. (Navy Historical Center)
27 September 1958...A typhoon caused the death of nearly 5000 people on Honshu, the main Japanese island. (Wikipedia)
28 September 1542...Portuguese explorer Juan Rodríguez Cabrillo sailed into present-day San Diego (CA) Bay during the course of his explorations of the northwest shores of Mexico on behalf of Spain. His landing at Point Loma Head apparently was the first known European encounter with California. Before dying on the Channel Islands off the Santa Barbara coast in January 1543, he had explored much of the California coast. (The History Channel)
28 September 1850...An Act of Congress (9 Stat. L., 500, 504) provided for the systematic coloring and numbering of all buoys for, prior to this time, they had been painted red, white, or black, without any special system. The act "prescribed that buoys should be colored and numbered so that in entering from seaward red buoys with even numbers should be on the starboard or right hand side; black buoys with odd numbers on the port or left hand side; buoys with red and black horizontal stripes should indicate shoals with channel on either side; and buoys in channel ways should be colored with black and white perpendicular stripes." (US Coast Guard Historians Office)
29 September 1959...Hurricane Gracie made landfall near Beaufort, SC with sustained winds of 97 mph and a peak gust of 138 mph. Ten people were killed in South Carolina and Georgia. As the weakening storm moved through Virginia on the 30th, the storm spawned an F3 tornado at Ivy, VA, which killed 11 people. On the same day, a storm produced 28 inches of snow in Colorado Springs, CO. (David Ludlum)
30 September 1932...Tropical cyclone rainfall of 4.38 inches at Tehachapi in southern California over 7 hours caused flash floods on Agua Caliente and Tehachapi Creeks resulting in 15 deaths. (The Weather Doctor)
30 September 1954...The USS Nautilus, the world's first nuclear-powered submarine, is commissioned by the U.S. Navy. In addition to breaking numerous submarine travel records to that time, the Nautilus made the first voyage under the Arctic sea ice at the geographic North Pole in August 1958, passing from the Pacific to Atlantic Ocean basins. The Nautilus was decommissioned on 3 March 1980 and is currently on display at the Submarine Force Museum in Groton, CT. (The History Channel)
30 September 1997...Omega Navigation Station Hawaii ceased operation, coinciding with the end of worldwide Omega transmissions. (USCG Historian's Office)