Weekly Ocean News

DATASTREME OCEAN WEEK NINE: 26-30 March 2007

Ocean in the News:

(Thurs.) Coordination is needed for a national water quality monitoring network -- Based upon the 2004 final report of the U.S. Commission on Ocean Policy and the U.S. Ocean Action Plan, NOAA recently released a report entitled "Linking Elements of the Integrated Ocean Observing System with the Planned National Water Quality Monitoring Network" that identifies the need for national water quality monitoring network. [NOAA News]
(Thurs.) Ancient Brazilian shoreline seen from space -- A photograph taken by an astronaut on board the International Space Station shows the ancient shoreline (or strandplain) along the Brazilian coast. [NASA Earth Observatory]
(Thurs.) Prehistoric hurricane activity is uncovered -- A scientist at Louisiana State University who is an expert in paleotempestology has been analyzing sediment cores obtained from the Gulf Coast and reports that major catastrophic hurricanes (Category 4 or 5 on the Saffir-Simpson Intensity Scale) have hit each drill site approximately 10 to 12 times during the past 3800 years, meaning that the chances of a given Gulf location being struck by a major hurricane in a given year is approximately 0.3 percent. [EurekAlert!]
(Thurs.) Alaskan sea lions could be threatened by changing ocean conditions -- Scientists at Alaska's North Pacific Universities Marine Mammal Research Consortium reported that recent changes in the ocean's climate over the last 30 years has changed the marine ecosystems in the waters around the 49th State and appear to have led to declines in the population of the endangered Steller sea lions. [EurekAlert!]
(Thurs.) Science-based management practices should address climate impacts -- The Marine Conservation Alliance recently released a report entitled "Conserving Alaska’s Oceans" prepared by Natural Resources Consultants, a Seattle (WA) research organization that describes the improved ocean conservation in the waters off Alaska due to a science-based management scheme, which the report recommends for other regions. [EurekAlert!]
(Tues.) Collaboration in promoting ocean health and homeland security -- NOAA research facilities in South Carolina and the US Department of Energy have reached a collaborative agreement to employ sensors to detect biological toxins and chemical hazards that would affect ocean health and water quality, as well as homeland security. [NOAA News]
(Tues.) Satellites used to detect changes in glacial ice -- Scientists have been using data collected by the NASA/German Aerospace Center's Gravity Recovery and Climate Experiment (Grace) that measures variations in gravity to map changes in the mass of ice sheets and glaciers. Several scientists at the University of Colorado, Boulder have determined that the Greenland ice sheet has lost 40,000 to 66,000 gallons of water per year in this decade, which could result in a rise in global sea level by almost 0.02 inches per year. [NASA Earth Observatory]
(Tues.) Climate history of tropical Africa reconstructed -- Scientists from the Royal Netherlands Institute for Sea Research and the University of Bremen have been studying the microfossils of soil bacteria in a marine sediment core taken from the outflow of the Congo River that has allowed them to reconstruct a temperature record for tropical Africa over the past 25,000 years. [Netherlands Organisation for Scientific Research]
(Tues.) Mercury entering the ocean through groundwater flow -- Researchers at Woods Hole Oceanographic Institution have determined that a substantial amount of dissolved mercury has been entering the ocean through submarine groundwater discharge, at rates that appear to be greater than those from atmospheric and river sources. [Woods Hole Oceanographic Institution]
(Tues.) Evidence found of early plate tectonics -- An international team of geoscientists claim that they have found evidence of active plate tectonics as early as 3.8 billion years ago in rocks preserved in southern Greenland. [EurekAlert!]
Earthquakes in western Pacific do not generate significant tsunamis --
- A magnitude 6.9 earthquake on Sunday in the Sea of Japan off the Japanese islands created a tsunami that propagated across the western North Pacific Ocean. Since the height of the tsunami was only six inches, the tsunami warning that had been issued was canceled. [CNN]
- Two powerful earthquakes, with magnitudes 7.2 and 6.2 were detected near the Pacific island nation of Vanuatu off the Australian continent on Sunday. A tsunami warning was issued, but no significant tsunami was reported. [CNN]
Tsunami Awareness Week in Alaska -- The Governor of Alaska, along with NOAA, has proclaimed this coming week (25-31 March 2007) as Tsunami Awareness Week in Alaska. This start of this week coincides with the 43^rd anniversary of the series of devastating tsunamis that struck southeastern Alaska following several earthquakes. [Governor's Office]
New homeport for NOAA ships -- Two NOAA research ships recently arrived at their new homeport on Ford Island in Oahu's Pearl Harbor. These ships, along with a third to be based there, will collect data for fisheries, coral reef and ocean research. [NOAA News]
NOAA hosts Science Fair -- Staff at the NOAA Science Center in Silver Spring, MD recently hosted a science fair for area students in grades four through six as a means of encouraging student interest in science careers. NOAA employees will also mentor students for three months. [NOAA News]
Space agency is involved in International Polar Year -- NASA scientists, including those at the Jet Propulsion Laboratory (JPL) and other NASA centers have joined colleagues from the US and more than 60 other countries in studying Earth's polar ice caps during the current International Polar Year (IPY) that commenced on 1 March and will conclude on 1 March 2009. JPL researchers are also studying the polar regions of the moon and Mars. [NASA Earth Observatory]
Delta preservation plan developed -- Researchers at Louisiana State University along with coastal scientists from around the world have published a document entitled "Restoration of the Mississippi Delta: Lessons From Hurricanes Katrina and Rita" that focuses attention on the importance of the Mississippi Deltaic Plain and the need for its preservation following the disastrous 2005 hurricane season. [EurekAlert!]
Recent levee report disputed by Corps of Engineers -- The US Army Corps of Engineers disputed a recently released report commissioned by the State of Louisiana that claimed the Corps was solely responsible for the decades of mistakes on the levee system in the New Orleans metropolitan area that resulted in floods following Hurricane Katrina. [USA Today]
"Snowball Earth" theory dismissed -- A team from the United Kingdom and Switzerland have recently provided evidence of the existence of hot-cold cycles in the Cryogenian period (850-544 million years ago) that would refute the previously held "snowball Earth" theory that an ice age at that time cause the Earth's ocean to freeze over. [EurekAlert!]
New method for determining origins of marine creatures developed -- Scientists at Scripps Institution of Oceanography have been developing a new system of "elemental fingerprinting" where chemical analyses are used to track the origins of tiny marine larvae. [Scripps Institution of Oceanography]
Development of deep-sea hydrothermal vents depends upon volcanic plumbing -- A geologist from the University of Oregon and colleagues have found that based on their measurement of the movements of ocean floors, the flow in the Earth's mantle has rotated beneath the East African Rise, resulting in the orientation of the plate boundary to change over time and that deep-sea hydrothermal vents frequently form above volcanoes where upwelling of the mantle and spreading of the plates are aligned. [EurekAlert!]
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: Controlling Nutrient Input into Chesapeake Bay

Chesapeake Bay is the nation's largest estuary; it is more than 300 km (185 mi) long, 65 km (40 mi) at its broadest, and averages about 20 m (66 ft) deep. The estuary was formed by the post-glacial rise in sea level that flooded the valley of the ancient Susquehanna River. The Bay receives about half its water from the Atlantic Ocean and the other half from the more than 150 rivers and streams draining a 166,000 square kilometer land area encompassing parts of New York, Pennsylvania, West Virginia, Delaware, Maryland, Virginia, and the District of Columbia. Major rivers that empty into Chesapeake Bay include the Potomac, Susquehanna, York, and James.

As described in more detail on pages 183-185 of your textbook, an estuary is a complex and highly productive ecosystem where seawater and freshwater runoff meet and mix to some degree. In Chesapeake Bay, more-dense seawater creeps northward along the bottom of the estuary, moving under the less-dense fresh water flowing in the opposite direction. This circulation combined with wind-driven and tidal water motions causes salinity to decrease upstream in the Bay, from values typical of the open ocean at its mouth to freshwater values at its northern margin.

As in all ecosystems, organisms living in estuaries depend on one another and their physical environment for food energy and habitat. Phytoplankton and submerged aquatic vegetation (e.g., marsh grass) are the primary producers (autotrophs) in estuarine food chains. Chesapeake Bay consumers (heterotrophs) include zooplankton, finfish, shellfish, birds, and humans.

Human activity has greatly modified Chesapeake Bay with consequences for the functioning of the ecosystem. Much of the original forests that covered its drainage basin were cleared and converted to farmland, roads, cities, and suburban developments. These modifications accelerated the influx of nutrients (i.e., compounds of phosphorus and nitrogen), sediment, pesticides, and other pollutants into the Bay. More nutrients spur growth of algal populations and when these organisms die (in mid-summer), their remains sink to the bottom. Decomposition of their remains reduces dissolved oxygen levels in the Chesapeake's bottom water. More sediment increases the turbidity of the water, reducing sunlight penetration for photosynthesis. Presently Chesapeake Bay is on the Federal list of "impaired waters" and in need of pollution abatement and remediation. States in the drainage basin have agreed to work together to clean up the Bay but there are significant obstacles including cost.

One casualty of human modification of the Chesapeake Bay ecosystem was marsh grass-reduced by 90% from historical levels. Marsh grass anchors sediment and dampens wave action thereby controlling shoreline erosion and turbidity. Marsh grass is a food source for many organisms including waterfowl and small mammals and serves as a primary nursery for crabs and many species of fish. Reduction of this habitat along with over-fishing has been implicated in the decline of populations of blue crabs, a mainstay of the Bay fishery for more than a century. Over the past decade, the number of adult female blue crabs plunged by 80%. Without adequate protection by marsh grass, blue crabs are more vulnerable to predation by striped bass (i.e., rockfish). Striped bass turned to blue crabs as a food source when fishing reduced the numbers of menhaden, their preferred food. Menhaden is a marine fish in the herring family and the Bay's top fishery by weight.

Human modification of the Chesapeake Bay drainage basin converted it from an essentially closed system to an open system. In the original climax forests, nutrients primarily cycled within the system with relatively little input to the Bay. Modification of the land for agriculture increased the area of the soil exposed to the elements and runoff from rain and snowmelt accelerated nutrient input into the Bay. In addition to such non-point (area) sources of nutrients are point sources including the effluent of wastewater treatment plants that discharge treated water into rivers and streams that drain into the Bay.

For decades, agriculture has successfully employed various cultivation practices that limit the runoff from cropland (e.g., contour plowing, strip cropping, and retention ponds.) However, less than one-third of the 300-wastewater treatment facilities located in the Chesapeake Bay drainage basin have the technology to remove high levels of nutrients from their effluent. Under current environmental regulations, states are not required to regulate the nutrient content of this discharge. But in late October 2003, the Chesapeake Bay Foundation, a private, not-for-profit environmental advocacy organization called on Virginia, Maryland, Pennsylvania, and the District of Columbia to specify nutrient limits on permits they grant to all wastewater treatment facilities. In support of their recommendations, the Chesapeake Bay Foundation cited the many water quality problems stemming from excessive nutrient load in the Bay waters (e.g., algal blooms, spread of "dead zones.") According to the U. S. EPA, under the federal Clean Water Act, a state can control nitrogen pollution if it determines that environmental harm is taking place. However, the EPA estimates that as much as $4.4 billion would be required to install state-of-the-art nutrient removal technologies at all major plants (those treating more than 500,000 gallons of wastewater per day).

Concept of the Week: Questions

In terms of nutrient cycling, the climax forest that originally occupied the Chesapeake Bay drainage basin was a(n) [(open)(closed)] system.
Excessive input of nutrients into Chesapeake Bay [(spurs the growth of)(has little impact on)] algal populations and [(increases)(reduces)] the concentration of dissolved oxygen in bottom waters.

Historical Events:

26 March 1845...Joseph Francis of New York City patented a corrugated sheet-iron lifeboat. (Today in Science History)
26 March 1946...The International Ice Patrol resumed after being suspended during World War II. (US Coast Guard Historians Office)
27 March 1513...Spanish explorer Juan Ponce de Leon sighted Florida (and the continent of North America) for the first time, mistaking it for another island. (Wikipedia)
27 March 1827...At the age of 18, Charles Darwin submitted his first report of an original scientific discovery to the Plinian Society in Edinburgh, Scotland. Darwin had made several discoveries about the biology of tiny marine organisms found along the Scottish coast. (Today in Science History)
27 March 1899...The first international radio transmission between England and France was achieved by the Italian inventor G. Marconi.
27 March 1930...The first US radio broadcast was made from a ship at sea.
27-28 March 1964...The most powerful earthquake in US history, the Good Friday Earthquake, rocked south central Alaska, killing 125 people and causing $311 million in property damage, especially to the city of Anchorage. The earthquake in Prince William Sound, which had a magnitude of 9.2 on the Richter scale, caused some landmasses to be thrust upward locally as high as 80 feet, while elsewhere land sank as much as 8 feet. This earthquake and submarine landslides also created a tsunami that also produced extensive coastal damage. A landslide at Valdez Inlet in Alaska generated a tsunami that reached a height of 220 feet in the inlet. A major surge wave that was approximately 100 ft above low tide caused major damage to Whittier (where 13 died) and other coastal communities in Alaska. The first wave took more than 5 hours to reach the Hawaiian Islands where a 10-foot wave was detected, while a wave that was 14.8 feet above high tide level traveled along portions of the West Coast, reaching northern California 4 hours after the earthquake. Nearly 10,000 people jammed beaches at San Francisco to view the possible tsunami, but no high-amplitude waves hit those beaches. Tsunami damage reached Crescent City in northern California. Tens of thousands of aftershocks indicated that the region of faulting extended a distance of about 600 miles. The Alaska Tsunami Warning Center was established because of this disaster, with a mission to warn Alaskan communities of the threat from tsunamis. [See the 1964 Prince William Sound Tsunami page from the University of Washington.] (Accord's Weather Guide Calendar) (US Coast Guard Historians Office)
27 March 1980...Waves to 20 feet and winds to 58 mph in the North Sea southwest of Stavanger, Norway led to the collapse of an oil rig accommodation platform. The deaths of 123 of the 212 people on the platform was the world's worst drilling catastrophe. (Accord's Weather Guide Calendar)
28 March 1848...USS Supply reached the Bay of Acre, anchoring under Mount Carmel near the village of Haifa, during expedition to explore the Dead Sea and the River Jordan. (Naval Historical Center)
28 March 1910...Henri Fabre became the first person to fly a seaplane after taking off from a water runway at Martigues near Marseilles, France. (Wikipedia)
29-31 March 1848...An ice dam at the neck of Lake Erie and the entrance to the Niagara River between Fort Erie, ON and Buffalo, NY caused by wind, waves and lake currents stopped flow of water over Niagara Falls for 30 hours, commencing during the late hours of the 29^th. (Accord's Weather Guide Calendar) (The Weather Doctor)
29 March 1910...The world's largest oceanographic museum was opened in Monaco through the generosity of Prince Albert I of Monaco, a great oceanographer, statesman, and humanitarian. This museum, a part of the Oceanographic Institute, has a grandiose facade overlooking the Mediterranean Sea. (Today in Science History)
29 March 1914...The Canadian Pacific liner Empress of Ireland, which had departed Quebec the previous day for Liverpool, collided with the Norwegian collier Storstad in the fog along the St. Lawrence River, sinking with the loss of 1024 passengers and crew.
29 March 1985...The Nantucket I was decommissioned, ending 164 years of lightship service. (USCG Historian's Office)
30 March 1923...The Cunard liner Laconia arrived in New York City, becoming the first passenger ship to circumnavigate the world, a cruise of 130 days. (Today in Science History)
31 March 1932...The United States signed the Whaling Convention at Geneva with 21 other countries. (USCG Historian's Office)
31 March 1995...Coast Guard Communication Area Master Station Atlantic sent a final message by Morse code and then signed off, officially ending more than 100 years of telegraph communications. (USCG Historian's Office)
31 March 2000...The water temperature of Lake Erie at Buffalo, NY was 39 degrees Fahrenheit on the last day of March, tying the maximum temperature for the date with that of 1998. Ice was present in 61 of 74 years on the 31^st, but this was third year in a row with open water. (Accord's Weather Guide Calendar)
1 April 1873...The British White Star steamship Atlantic sank off Nova Scotia killing 547 after striking an underwater rock near Meagher's Island while on a voyage from Liverpool, England to New York City. Only 413 people survived. (Wikipedia)
1 April 1946...The Scotch Cap Lighthouse on Unimak Island in Alaska's Aleutian Islands was shaken by two earthquakes in a 27 minute span, then obliterated by a tsunami wave. The entire five-man crew was killed and the lighthouse antenna (105 ft above sea level) was washed away. Some debris was found 115 ft above sea level. The tsunami that propagated across the Pacific Ocean was responsible for more than 165 fatalities and over $26 million in damage. Many of the casualties were on the Hawaiian Islands, especially in Hilo on the Big Island. This tsunami was responsible for the development of the current Pacific Tsunami Warning System. (University of Washington) (Accord's Weather Guide Calendar) (US Coast Guard Historian's Office)