Weekly Ocean News

DATASTREME OCEAN WEEK NINE: 30 October-3 November 2006

Ocean in the News:

(Thurs.) Funding provided for study of Florida's state algae bloom events -- The Fish and Wildlife Research Institute, a part of the Florida Fish and Wildlife Commission, has received funding from NOAA's Ecology and Oceanography of Harmful Algal Blooms program to study the underlying causes of the harmful algae blooms (also known as "red tide") that have recently occurred along the Gulf Coast of the Sunshine State. [NOAA News]
(Thurs.) Wind component added to coral bleaching warning system -- The NOAA Coral Reef Watch now has an experimental near-surface wind forecast product based the satellite-based wind observations from the QuickSCAT scatterometer instrument onboard NASA and NOAA satellites. [NOAA News]
(Thurs.) Amazon River had reversed flow -- Geologists at the University of North Carolina in Chapel Hill claim that their analysis of zircon crystals buried in the Amazon Valley indicate that the Amazon River once flowed to the west, but reversed course and currently flows from west to east following the creation of the Atlantic Ocean during the Cretaceous Period (65-145 million years ago) and the subsequent building of the Andes. [EurekAlert!]
(Thurs.) Moorings to monitor the "pump" -- British scientists are leading a project that places an array of subsurface monitors across the Atlantic Ocean to check on the temperature and salinity of the waters. The data will hopefully provide an early warning of weakening of the Meridional Overturning Circulation (MOC), sometimes called the thermohaline circulation. Changes of the MOC would lead to major climate impacts for Europe. [BBC News]
(Tues.) First images obtained from an international weather satellite -- Some of the first images were obtained from the NOAA Advanced Very High Resolution Radiometer (AVHRR) that is onboard the recently launched MetOp-A, the European polar-orbiting satellite that is part of the U.S.-European Initial Joint Polar System. [NOAA News]
(Tues.) A new coastal mapping vessel to be built -- NOAA officials recently announced that a Pascagoula, MS shipbuilder will build a new Small Waterplane Area Twin Hull Coastal Mapping Vessel or (SWATH CMV) with sophisticated sonar that will collect depth data from the full seafloor in coastal waters for production of new nautical charts. [NOAA News]
(Tues.) Historic pre-incident surveys of coastal shoreline is launched -- Officials with the NOAA Office of Response and Restoration and the U.S. Navy recently announced that they have been collaborating in the first surveys of potential threats to coastal shorelines due to hazardous material leaks or spills. Pearl Harbor in Hawaii was the first site for the survey. [NOAA News]
Eye on the tropics --
- In the eastern Pacific, former Hurricane Paul made landfall early Thursday morning along the western Mexican coast as a tropical depression. At the start of last week, an image from the MODIS sensor (Moderate Resolution Imaging Spectroradiometer) on NASA’s Terra satellite captured the spiral bands of clouds and the eye of Paul south of Baja California. [NASA Earth Observatory]
  Tropical Depression 18-E formed last Thursday and moved westward across the eastern North Pacific. A visible image made by sensors on NOAA's GOES-11 satellite captures clouds from Tropical Depression 18-E. [NOAA OSEI]
- In the western North Pacific, Supertyphoon Cimaron formed late Friday east of Luzon in the Philippines and moved westward to become a category 5 typhoon on the Saffir-Simpson Scale on Sunday. By late Sunday this typhoon, with maximum sustained winds of over 143 mph made landfall in the northern Philippines as one of the most intense storms to ever hit the country. [USA Today] A visible image from Japan's MTSAT-1 satellite shows Supertyphoon Cimaron hours prior to landfall on Luzon. [NOAA OSEI]
What has happened to the Atlantic hurricane season? -- While coastal residents are relieved that the pre-hurricane season forecasts of much above average hurricane activity in the North Atlantic have not come true so far this season, researchers at the National Hurricane Center and Colorado State University are attempting to determine how the effects of a developing El Niño episode and upper tropospheric wind patterns have had on reducing the actual number of hurricanes below the earlier forecasts. [USA Today]
New York City could be at risk from hurricanes and sea level rise -- A team of scientists with the Goddard Institute for Space Studies have been collaborating with colleagues at New York City's Department of Environmental Protection to determine the impact that future rises in sea level, along with the approach of hurricanes, would have upon residents of New York City based upon the output from a variety of computer models. [NASA Earth Observatory] Additional information and images are available from a NASA website. [NASA]
Coastal flood events not new to Gulf Coast -- An oceanographer at Rice University recently reported that his research of the Gulf Coast over the last 10,000 years indicates every bay along the Texas and Louisiana Gulf coast is vulnerable to significant flooding and expansion due to rising sea levels and a reduction in sill flowing from dammed rivers. He warns that these rapid flooding events have occurred before. [EurekAlert!]
Ocean bacteria could have a "switch gene" that could affect global climate change -- Researchers at the University of Georgia report the discovery of a "switch gene" in two groups of marine bacterioplankton that appear to regulate the emission of sulfur compounds from the oceans into the atmosphere in sufficient quantity that would affect the global climate. [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 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:

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)