WEEK NINE: 31 October-4 November 2011

• Opportunity for Teachers: The National Ocean and Atmospheric Administration's (NOAA) Teacher at Sea 2012 Field Season program is now accepting applications until 30 November 2011. 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.

• Eye on the tropics -- The weather across the Northern Hemisphere tropical ocean basins was relatively quite last week. However, a tropical storm formed one week ago Sunday night over the waters of the western Caribbean Sea offshore of Central America. This tropical storm was named Rina, the seventeenth named tropical cyclone of the 2011 Atlantic hurricane season. By Monday afternoon, this system had intensified to become the year's sixth hurricane in the basin as it traveled to the northwest just off the Central American coast. Hurricane Rina intensified into a strong category 2 hurricane (on the Saffir-Simpson Scale) by midweek as it headed for the coast of Belize and Mexico's Yucatan Peninsula. However, this hurricane weakened and turned toward the north as it was close to the coast. Rina weakened to a tropical storm and then to a tropical depression as it reached the Yucatan Channel. By last Friday afternoon, Rina became a remnant low. Heavy rain and some high waves associated with Rina battered the Yucatan coast [USA Today]. Since extended forecasts made early last week had projected Hurricane Rina to reach the Florida Keys, the 15th NASA Extreme Environment Mission Operations (NEEMO) ended earlier than planned. NOAA, the agency operating the Aquarius Undersea Laboratory, determined that Rina posed a risk to the safety of the mission taking place near Key Largo, FL and elected to bring the six submerged aquanauts back to the surface last Wednesday. [NASA Headquarters] Additional information along with satellite images for Hurricane Rina are available from the NASA Hurricane Page.
• Funding provided for collaborative hurricane research -- During the past week, NOAA's Office of Weather and Air Quality announced that 12 multi-year proposals have been funded to aid university and federal scientists involved with tropical cyclone research in an attempt to obtain more rapid transfer of new technology, research results, and observational advances through NOAA's Joint Hurricane Testbed. [NOAA News]
• Northeast skate quota increased --Based upon new scientific information showing that the overall population of skate, a type of cartilaginous fish, has increased, NOAA has increased the amount of skate that can be caught in waters off the Northeast coast between the end of November 2011 and the end of April 2012. [NOAA News] In a letter to US Senator John Kerry of Massachusetts, NOAA Administrator Dr. Jane Lubchenco discussed the current health status of the Northeast groundfish industry and the efforts being undertaken by her agency to address the needs and concerns of this industry. [NOAA News] [NOTE: This link requires Adobe Acrobat Reader. See link below]
• Bacterial infection appears to have claimed five dolphins -- NOAA recently reported that pathologists have identified the Brucella bacteria as apparently being the cause of the deaths of five bottlenose dolphins in the northern Gulf of Mexico since early 2010. The investigation continues. [NOAA News]
• Antarctic killer whales recuperate in tropical waters -- Scientists from NOAA's Southwest Fisheries Science Center report that Antarctic killer whales appear to migrate rapidly to warm tropical waters in order to regenerate skin tissue after being coated with diatoms or algae for months in the colder waters surrounding Antarctica. [NOAA Fisheries Service]
• Successful launch of nation's newest environmental satellite -- Last Friday, the NPOESS Preparatory Project (NPP) spacecraft payload was launched by NASA from Vandenberg Air Force Base, CA and successfully placed into orbit. This polar-orbiting NPP spacecraft features five new instruments that will collect detailed information about Earth's atmosphere, land and oceans. These data will be vital for NOAA’s weather and climate forecasting mission. [NOAA News] [NASA] Photos and video of the launch are available. [NASA Earth Observatory]
• Crack seen in an Antarctic glacier ice shelf -- During two recent flights on the NASA DC-8 aircraft, researchers participating in the Operation IceBridge project have found and inspected a crack running across the floating ice shelf of the fast moving Pine Island Glacier along the West Antarctic coast. The rapid thinning of this marine glacier is of concern to scientists because it could contribute to sea level rise. [NASA Blogs] Nearby, scientists from Lamont -Doherty Earth Observatory have been studying the retreat of the fast-flowing Thwaites Glacier, which drains into west Antarctica's Amundsen Sea. The scientists are expecting the melting to accelerate within the next two decades, once the glacier detaches from an underwater ridge. Some of the data from this glacier were collected by NASA's IceBridge campaign in 2009. [Lamont -Doherty Earth Observatory]
• Prehistoric data from ocean floor could help predict future climate -- Scientists at the University of Missouri, the University of Florida and the United Kingdom's University of Manchester report that their examination of deep ocean temperature and circulation data approximately 70 million years ago during the "greenhouse climate" of the late Cretaceous Epoch provides evidence of a warm and salty water mass in the Atlantic basin moving south. They claim that their research should help in the understanding of the potential consequences of future increases in greenhouse gases. [University of Missouri News Bureau]
• Seaweed could be affected by ocean warming -- A scientist at the University of Western Australia reports that the herbarium records collected in the waters surrounding Australia since the 1940s reveals that nearly one quarter of the temperate seaweed species in these waters could be headed to extinction because of increased ocean temperatures due to a changing climate. [EurekAlert!]
• 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, 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, 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 227-229 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. Environmental Protection Agency (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

1. In terms of nutrient cycling, the climax forest that originally occupied the Chesapeake Bay drainage basin was a(n) [(open)(closed)] system.
2. 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.

• 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)
• 6 November 1528...Shipwrecked Spanish conquistador Álvar Núñez Cabeza de Vaca became the first known European to set foot on Texas soil, near present-day Galveston Island. (Wikipedia)

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Prepared by AMS DS Ocean Central Staff and Edward J. Hopkins, Ph.D., email hopkins@meteor.wisc.edu
© Copyright, 2011, The American Meteorological Society.