Weekly Ocean News

DATASTREME OCEAN WEEK EIGHT: 23-27 October 2006

Welcome to the participants at the Geological Society of America's 2006 Annual Meeting and Exposition that is being held in Philadelphia, PA from 22-25 Oct 2006.

Ocean in the News:

(Thurs.) Warming a suspect in impending reef death -- Scientists meeting in the US Virgin Islands predict that more than half of the coral reefs in the world will be dead in 25 years, due in large part to global warming. Up to 30% have died in the last 50 years and more are under stress. [CNN]
(Thurs.) Demise of early dinosaurs due to "sick earth" syndrome? -- Researchers from the University of Southern California offer an alternative explanation to the Permian-Triassic mass extinction of species including the early dinosaurs roughly 250 million years ago, suggesting ocean warming that led to reduced circulation, increased levels of hydrogen sulfide and reduced dissolved oxygen as a possible cause. One of the most offered current explanations to the mass extinction has been the bombardment of the planet by meteor hits. [EurekAlert!]
(Thurs.) Adapting to oxygen on an early earth -- Scientists at the Carnegie Institution and Penn State University have discovered that some marine microbes appear to have adapted to living with oxygen approximately 2.72 billion years ago, roughly 300 million years prior to the rise of atmospheric oxygen. [Carnegie Institution]
(Thurs.) New radar technique used to study Antarctic ice shelf -- The scientists with the British Antarctic Survey have developed a new technique that involves phase-sensitive radar to study the internal structure of a large section of the Antarctic ice shelf, which should help them determine how the ice sheet is responding to changes in climate. [EurekAlert!]
(Thurs.) A warmer and wetter planet foreseen -- Following their analysis of the results of simulations using several advanced numerical climate models made for the Intergovernmental Panel on Climate Change, scientists at the National Center for Atmospheric Research, Texas Tech University and the Australian Bureau of Meteorology Research Centre have concluded that the planet could face an increased risk of heat waves, more intense precipitation events and other climatic extremes, including drought, during the next century. [UCAR/NCAR]
(Tues.) Seafood is affirmed as a healthy food choice -- Officials from NOAA, the Food and Drug Administration and the Harvard School of Public Health recently held a news conference where the results of a study entitled "Seafood Choices: Balancing Benefits and Risks" were discussed. This study affirms the point that Americans can decrease their risk for heart disease by eating at least two meals of fish per week. [NOAA News]
(Tues.) Japanese will cut tuna fishing quotas -- The Japanese Fisheries Agency recently announced that it will reduce its quota for fishing southern bluefin tuna off Southeast Asia. [New Scientist]
(Tues.) Iceland plans on resuming commercial whaling -- The Icelandic Fisheries Minister told that nation's parliament last week of his ministry's plan to issue licenses thereby allowing resumption of commercial whaling following a 17-year moratorium, despite a worldwide ban. [ENN] The US Secretary of Commerce expressed disappointment with Iceland's resumption of whale hunting. [NOAA News]
(Tues.) Targeted fish species are placed in "double jeopardy" -- Long-term ocean data collected for the California Cooperative Oceanic Fisheries Investigations by scientists at Scripps Institution of Oceanography, the Southwest Fisheries Science Center, Imperial College London and the University of Oxford indicates that fishing carries a "double jeopardy" impact for various targeted fish species by amplifying the highs and lows of natural population variability, thereby increasing the risk for a collapse in the fisheries. [Scripps Institution of Oceanography]
Eye on the tropics -- In the eastern Pacific Tropical Depression 17-E developed in the predawn hours of Saturday morning offshore of the Mexican coast. Later in the morning, it had intensified to become Tropical Storm Paul, the sixteenth named tropical cyclone of the 2006 hurricane season in that basin. By Sunday, Tropical Storm Paul had intensified as it continued to move toward the west.
Winter Outlook and El Niño watch updated -- Forecasters at the Climate Prediction Center released their latest winter outlook covering the three-month winter season (December 2006-February 2007) that indicates that much of the nation should experience a better than even chance that this winter will be warmer than the 30 year "normals" (based on the 1971-2000 interval), but slightly cooler than last year's winter season. Only the Southeast could experience a slightly above chance for near average temperatures, while the Hawaiian Islands could experience a good chance of below average temperature readings. The Southwest and the Southeast could have a better than even chance of wetter than normal winter weather, while the northern Rockies and the Ohio Valley could have drier than average conditions. These outlooks are predicated on a strengthening El Niño event that continues. Researchers indicate that above average sea surface temperatures in the tropical Pacific along with other indicators have resulted in a weak El Niño that could continue for the next several months, but not gaining the strength of the major 1997-1998 El Niño event. [NOAA News]
Greenland Ice sheet continues to loose mass -- Scientists at the have used data collected by sensors onboard by NASA’s GRACE (Gravity Recovery and Climate Experiment) satellites to determine that while some regions on the Greenland ice cap have shown increased accumulation, the island has been rapidly loosing mass near the coasts through melting and iceberg calving during the last several years. [NASA Earth Observatory] Additional images are available. [NASA Life on Earth]
Beaked whales are found to make extreme dives -- Researchers at Woods Hole Oceanographic Institution, the University of La Laguna, the University of Aarhus, Bluwest and the NATO Undersea Research Centre in Italy have found that two species of beaked whales (Cuvier's and Blainville’s) are capable of extreme dives to depths of more than 4000 feet as they hunt for deepwater prey in waters off Italy and Spain. [Woods Hole Oceanographic Institution]
Grant to model and forecast harmful algal blooms in Gulf of Maine is awarded -- The Woods Hole Oceanographic Institution recently was awarded money for the initial year of a five-year grant that would extend its harmful algal bloom observation, modeling and forecasting program to mew areas of the Gulf of Maine. [NOAA News] A variety of monitoring strategies will be employed, including research cruises, autonomous gliders, drifters, moored instruments and satellite imagery. [Woods Hole Oceanographic Institution]
Global and US Hazards/Climate Extremes -- A review and analysis of the global impacts of various weather-related events, including drought, floods, and storms during the current month. [NCDC]
Earthweek -- Diary of the Planet [earthweek.com] Requires Adobe Acrobat Reader.

Concept of the Week: Loss of Louisiana's Coast

According to the Louisiana Coastal Wetlands Conservation and Restoration Task Force, Louisiana has been losing its coastal wetlands (bayous, marshes, and swamps) to the waters of the Gulf of Mexico at an alarming rate of about 65 to 100 square km (25 to 38 square mi) per year for the past several decades. This loss adversely affects fisheries in the Gulf of Mexico and makes the coastal zone more vulnerable to storm surges such as that produced by Hurricane Katrina in August 2005. Since the early 1930s, the state's coastal wetlands have shrunk by an area equivalent to the state of Delaware. According to USGS estimates, an additional 1800 square km (700 square mi) could be lost by mid-century. The price tag for reversing this trend, restoring some marshes, and protecting the remaining 15,000 square km (5800 square mi) of wetlands could top $14 billion and take decades to complete. Many people argue that the value of Louisiana's coastal wetlands is well worth the expense.

As much as 75% of the fish and other marine life in the northern Gulf of Mexico depend on Louisiana's coastal wetlands. The wetlands are a nursery for commercially important shellfish such as shrimp, crawfish, blue crab, and oysters. It is a food source for larger fish including yellow fin tuna, red snapper, and swordfish. In 2003, about three-quarters of the nation's fish and shellfish catch by weight came from Louisiana's waters. In addition, the wetlands are a stopover for millions of birds migrating between North and Central/South America. Furthermore, wetlands and associated barrier islands protect the ports, buildings, and other coastal zone structures from storm surges. Wetlands are particularly important in buffering the levees surrounding New Orleans, much of which is below sea level.

Many factors contribute to the loss of Louisiana's coastal wetlands. Thousands of kilometers of pipelines transporting oil and natural gas through the marshes plus the extensive network of navigation channels allow saltwater to intrude the wetlands. Increased salinity of the originally fresh or brackish waters kill wetland grasses, shrubs, and other vegetation that anchor soil in place. The canals also allow tidal currents to flow farther inland, accelerating erosion of wetland soils. The most important factor, however, is the consequence of flood control structures (levees) constructed along the banks of the Mississippi River. Levees constrict the flow of the river so that waters and suspended sediment discharge rapidly into the Gulf. Deprived of a continuous input of sediments and vegetation-supporting nutrients, existing sediments compact, wetlands subside and Gulf waters invade the wetlands. With the anticipated continued rise in sea level due to global climate change (discussed in Chapter 12 of your DataStreme Ocean textbook), erosion of Louisiana's coastal wetland may accelerate in the future.

Plans to reverse the loss of Louisiana's coastal wetlands (the Coast 2005 plan and the Louisiana Coastal Area plan) seek to restore the structure and function of coastal wetlands. One proposal is to breach some levees along the lower Mississippi. This partial diversion of the Mississippi would increase the supply of sediments to the wetlands. Closing or installing locks on some navigation canals would reduce saltwater intrusion. In addition, dredged sediment would be used to re-build wetlands and restore barrier islands.

Concept of the Week: Questions

The most important factor contributing to erosion of Louisiana's coastal wetlands is [(saltwater intrusion)(levees along the banks of the Mississippi River)].
Global climate change that is accompanied by a rise in sea level is likely to [(accelerate)(have no effect on)] the rate of erosion of Louisiana's coastal wetlands.

Historical Events:

23-24 October 1918...The Canadian steamship Princess Sophia carrying miners from the Yukon and Alaska became stranded on Vanderbilt Reef along coastal British Columbia. A strong northerly gale hampered rescue attempts, and the next day, the ship sank with the loss of the 268 passengers and 75 crewmen onboard. (The Weather Doctor)
25 October 1859...The Royal Charter Storm, named after the loss of the fully rigged ship Royal Charter off the coast of Anglesey, England, drowned about 500 people, along with the loss of gold bullion. The ship was one of over 200 vessels wrecked between 21 October and 2 November, with the loss of around 800 lives. This tragedy led to the introduction of gale warnings in June 1860. (The Weather Doctor)
25 October 1941...South Greenland Patrol expanded to include three cutters of the Northeast Greenland Patrol and form the Greenland Patrol. (USCG Historian's Office)
25-26 October 1980...The combination of unusually high tides and southeasterly winds gusting to 75 mph generated waves with heights to 25 ft, resulting in serious flooding, beach erosion and sea wall damage along the Maine coast. Wind damage was considerable and as many as 100,000 homes were without power for up to 40 hrs. (Accord Weather Guide Calendar)
27 October 1728...Captain James Cook, the famed British naval officer who was one of the first of the scientific navigators, was born on this date. Captain Cook surveyed the coasts of Labrador and Newfoundland before making three expeditions into the Pacific Ocean where he became the first Englishman to explore previously uncharted locations. On his various voyages, he conducted astronomical observations and his ship's botanist studied the flora and fauna that were collected. (Today in Science History)
28 October 1492...The famous Italian explorer, Christopher Columbus, landed on Cuba. (Wikipedia)
28 October 1991...Typhoon Thelma devastated the Philippines. Reports indicated that 6000 people died by catastrophic events related to the storm including dam failure, landslides, and extensive flash flooding. The greatest number of casualties occurred on Leyte Island where an 8-ft storm surge struck Ormoc, accounting for over 3000 fatalities. (The Weather Doctor)
29 October 1999...Tropical Cyclone 5B, with sustained winds of 155 mph, made landfall at Paradwip (Orissa, India). A storm surge of at least 20-ft height swept at least 12 mi inland. More than 10,000 people were killed. With 2 million homes either damaged or destroyed, 35 million people were left homeless. Damage from this tropical cyclone was $1.5 billion. (Accord Weather Guide Calendar)