Weekly Ocean News

DATASTREME OCEAN WEEK NINE: 29 October-2 November 2007

Opportunity for Teachers: The National Ocean and Atmospheric Administration's (NOAA) Teacher at Sea program is now accepting applications until December 31, 2007. 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.

Ocean in the News:

(Thurs.) Northeast fisheries studied for groundfish -- Officials with NOAA's Fisheries Service recently determined that an apparent fisheries disaster did not occur with the stocks of groundfish in the waters off northern New England. [NOAA News]
(Thurs.) Chemistry and physics important in dynamics of earth's interior -- Seismologists at Arizona State University report that the chemistry of the earth's upper mantle is just as important as temperature and pressure in affecting the dynamics of the earth's deep interior. [EurekAlert!]
(Thurs.) Unexpected increases in carbon dioxide detected -- Researchers affiliated with the Global Carbon Project, the University of East Anglia and the British Antarctic Survey report that the concentration of atmospheric carbon dioxide has increased at a greater rate than expected since 2000 from the inefficient use of fossil fuels and from the decline in the efficiency of land and ocean carbon sinks. [EurekAlert!] [CSIRO]
(Tues.) Hawaiian coral ecosystems are studied-- Four organizations in Honolulu, HI have received a $500,000 award from NOAA that will fund the first year of a three-year project designed to study deep-water coral reef ecosystems that are found in the waters surrounding the Hawaiian Islands. [NOAA News]
(Tues.) Meteor may not have been prime suspect in "Great Dying" mass extinction -- Geologists at the University of Southern California claim that the "Great Dying", the Permian-Triassic mass extinction event approximately 250 million years ago may have been caused by slower environmental stress caused by volcanic eruptions and increased global temperatures, rather than the more rapid stress associated with a major meteor impact as commonly thought. This study also suggests that deep sea organisms began dying before those on reefs and ocean shelves, which may mean that hydrogen sulfide may have been released due to higher ocean temperatures. [EurekAlert!]
(Tues.) Increased risks foreseen with less Arctic ice cover -- At a meeting held at the European Space Agency's Earth Observation Centre in Frascati, Italy, polar ice experts from North America and Europe associated with the International Ice Charting Working Group warn that the diminished Arctic sea ice could pose of "significant hazards to navigation." These experts are relying on satellites to provide important up-to-date information for their forecast models. [ESA]
Eye on the tropics -- During the past week, the following tropical cyclone activity was detected:
- In the North Atlantic basin, Tropical Depression 16 formed over the central Caribbean Sea south of Hispaniola early Saturday morning. By Sunday afternoon this depression had intensified to Tropical Storm Noel, the fourteenth named tropical cyclone of the 2007 North Atlantic hurricane season. [USA Today]
- In the eastern North Pacific, Tropical Storm Kiko traveled northwestward parallel to the Mexican coast at the start of last week, but then turned west. This storm weakened to a tropical depression as it moved to west-southwest away from the Mexican coast by midweek.
- In the western North Pacific basin, Tropical Storm Faxai developed to the southeast of Okinawa late last week and initially traveled toward the northwest, before curving toward the north and then northeast.
- In the Indian Ocean, Tropical Cyclone 5 A formed over the weekend to the northwest of the Maldives and was moving to the west.
Hypoxia forecasting models are developed for two East Coast estuaries -- The University of Maryland Center for Environmental Science has been awarded $330,000 by NOAA to begin a five-year project designed to develop hypoxia forecasting models that will assist resource managers analyze and predict how hypoxia, water quality, and fishery production respond to nutrient loading and climatic factors in Chesapeake Bay and Delaware inland bays [NOAA News]
A paleo-thermometer developed -- A researcher working at the Royal Netherlands Institute for Sea Research developed an instrument that measures the changes in the cell wall composition of archeabacteria that are related to changes in seawater temperature. This paleo-thermometer can be used for climate reconstruction. [Netherlands Organisation for Scientific Research]
North Atlantic carbon uptake slowed -- Scientists from the United Kingdom's University of East Anglia report that uptake of atmospheric carbon dioxide by the North Atlantic, which represents a major carbon sink, slowed dramatically beginning in the mid 1990s and continued for the first several years of the new millennium. [EurekAlert!]
Satellites enhance marine security -- Data collected by radar sensors onboard the European Space Agency's ERS-2 satellite have been used by governmental security agencies across Europe to monitor illegal marine trafficking. [ESA]
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 DataStreme Ocean 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:

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)
30 October-1 November 1991...After absorbing Hurricane Grace on the 29^th, an intense ocean storm took an unusual course and moved westward along 40 degrees north latitude and battered eastern New England with high winds and tides. Winds had already been gusting over 50 mph along the coast 2 days before, so seas and tides were very high. Major coastal flooding and beach erosion occurred all along the New England, New York, and New Jersey coasts. Over 1000 homes were damaged or destroyed with tides 4 to 7 ft above normal. Wind gusts reached 78 mph at Chatham, MA and 74 mph at Gloucester, MA. A ship east of New England reported a 63-ft wave. Total damage from the storm was $200 million. On 1 November this ocean storm underwent a remarkable transformation. Convection developed and rapidly wound around the storm center and an eye became visible on satellite imagery. Air Force reconnaissance aircraft found a small but intense circulation with maximum winds of 75 mph. This evolution from a large extratropical low to a small hurricane is rare but not unprecedented. (Intellicast)
31 October 1874...A waterspout (a tornado-like vortex that travels over water) formed over Lake Erie and reached the lakeshore approximately 0.5 mi west of Buffalo, NY. Upon reaching the shore, it dissipated, scattering sand in all directions. (Accord Weather Guide Calendar)
31 October 1876...A 10 to 50 ft storm surge ahead of the Backergunge cyclone flooded the eastern Ganges Delta in India (now Bangladesh). Over 100,000 people drowned. (The Weather Doctor)
1 November 1521...Four ships in the fleet commanded by the explorer Ferdinand Magellan began sailing through the passage immediately south of mainland South America connecting the Atlantic and Pacific Oceans, now known as the Strait of Magellan. Because this passage began on All Saints Day, Magellan initially called the 373-mile long passage, the Estreito (Canal) de Todos los Santos , or "All Saints' Channel". (Wikipedia)
1 November 1755...Lisbon, Portugal was destroyed by a massive earthquake and tsunami, killing between 60,000 and 90,000 people. (Wikipedia)
1 November 1859...The current Cape Lookout, NC lighthouse was lit for the first time. Its first-order Fresnel lens can be seen for nineteen miles. (Wikipedia)
1 November 1861...A hurricane near Cape Hatteras, NC battered a Union fleet of ships attacking Carolina ports, and produced high tides and high winds in New York State and New England. (David Ludlum)
1 November 1884...Greenwich Mean Time (GMT) was nearly unanimously adopted at a meeting of 25 nations at the International Meridian Conference in Washington, DC. This time is also called Greenwich Meridian Time because it is measured from the Greenwich Meridian Line at the Royal Observatory in Greenwich, England. At that time, the International Date Line was also drawn and 24 time zones created. (Today in Science History)
2 November 1493...Explorer Christopher Columbus first sighted the island of Dominica in the Caribbean Sea.
3 November 1975...The North Sea pipeline, Firth of Forth, was opened by Queen Elizabeth II. The first oil was piped ashore from the North Sea at Peterhead, Scotland in a pipe that ran from British Petroleum's "Forties Field" for 110 miles along the seabed and then 130 miles to the oil refinery at Grangemouth. The field was discovered by the drilling rig Sea Quest in October 1970. (Today in Science History)