DATASTREME OCEAN WEEK NINE: 25-29 March 2013

ITEMS OF INTEREST

• Tsunami Awareness Week -- NOAA and the National Tsunami Hazard Mitigation Program (a partnership between NOAA, the United States Geological Survey, the Federal Emergency Management Agency, the National Science Foundation, and the 28 U.S. Coastal States, Territories, and Commonwealths) have designated this upcoming week (24-30 March 2013) as National Tsunami Awareness Week. Tsunami awareness training exercises will be conducted for the states and territories along the Pacific that is called Pacific Tsunami Exercise (PACIFEX 13). Open houses will be held at the National Weather Service's tsunami warning centers in Alaska and Hawaii, along with various community activities in coastal states. The Governor of Alaska has proclaimed this coming week as Tsunami Awareness Week in Alaska. This week coincides with the 49th anniversary of the series of devastating tsunamis that struck southeastern Alaska following several earthquakes. [Governor's Office for State of Alaska]
• Participate in fourth campaign of Worldwide GLOBE at Night 2013 -- The fourth in a series of GLOBE at Night citizen-science campaigns for 2013 will begin next Sunday (31 March) and continue into the following week, running through 9 April. GLOBE at Night is a worldwide, hands-on science and education program designed to encourage citizen-scientists worldwide to record the brightness of their night sky by matching the appearance of a constellation (Orion or Leo in the northern hemisphere, and Orion and Crux in the southern hemisphere) with seven star charts of progressively fainter stars. In addition to this campaign and the three previously held in early weeks of January, February and March, the one additional GLOBE at Night campaigns will be in 2013: 29 April-8 May. Check the GLOBE at Night website for additional information on this week's activities plus a Teacher Information Page and activity packet.
• Asteroids, climate change and mass extinctions -- You are invited to read this week's Supplemental Information...In Greater Depth that describes how geoscientists have gathered evidence of five major mass extinctions over the last 550 million years from fossil records. These records also help in reconstructing past climates and help in the understanding of climate change.

Ocean in the News:

• Eye on the tropics --- Only one organized tropical cyclone was detected across the planet's ocean basins last week. In the western South Pacific Ocean basin, Tropical Storm Tim dissipated early in the week (local time) as it traveled to the southwest across the Coral Sea toward the southeastern coast of Australia's Queensland. Satellite images and additional information on Tropical Storm Tim can be found on the NASA Hurricane Page .
• Algae in Gulf use toxins as a shield when hungry -- Scientists from NOAA's National Centers for Coastal Ocean Science and North Carolina State University report that a species of marine algae in the Gulf of Mexico that are responsible for what is often known as a "red tide" protects itself from predators by becoming highly toxic when hungry and most vulnerable. The "red tide" or Harmful Algal Blooms (HABs), plague Gulf Coast communities. [NOAA's National Centers for Coastal Ocean Science News]
• Effects of Arctic oil and gas activities on marine mammals and Alaska native communities to be considered -- Last week officials with NOAA's Fisheries announced that it is seeking public comments through the end of March on a supplemental draft environmental impact statement (EIS) for oil and gas activities in the Arctic Ocean. The (EIS) draft, which was developed in collaboration with the US Department of the Interior's Bureau of Ocean Energy Management, includes analysis on how a broader range of potential offshore oil and gas activities could affect the environment, with a specific focus on marine mammals and the Alaska Native communities that depend on these animals for food and cultural traditions. [NOAA Fisheries]
• More frequent extreme storm surges in future -- In research conducted at Denmark's Niels Bohr Institute, scientists have found that a tenfold increase in the frequency of extreme storm surges produced by tropical cyclones (primarily from hurricanes) would occur if the global temperatures would increase by two Celsius degrees. They based their conclusions from daily tide data from monitoring stations along the US Atlantic and Gulf coasts extending back to 1923. Statistical climate models were used to predict the number of hurricane surges 100 years into the future. [Niels Bohr Institute]
• Florida manatees take winter refuge in warm springs -- Analysis of organized annual statewide winter counts of the endangered Florida manatees by the Florida Fish and Wildlife Research Institute has indicated that the manatees rely on warm-water refuges in the waters around the southern two-thirds of the Florida Peninsula during winter cold spells. The manatees consistently return to specific refuges that include warm water discharges from power plants and warm-water springs. The researchers found that hot springs offered the manatees the best protection of the refuges studied. Therefore, protecting and improving access to these warm springs may be critical for the long-term survival of Florida manatees. [PLoS ONE]
• Greenland's peripheral glaciers provide significant contribution to sea-level rise -- Scientists from Switzerland's University of Zurich and colleagues participating in the European Union's Ice2sea program claim that the contribution made by those Greenland glaciers separated from the ice sheet to global sea-level rise constitutes approximately ten percent of the estimated contribution of the entire world's glaciers and ice caps. Furthermore, this contribution is higher than expected. The researchers recently completed an inventory of Greenland's glaciers and ice caps, using lasers to measure the height of the ice from space and to determine changes in the mass of those ice bodies, separate from the main ice sheet. [EurekAlert!]
• Evolution of early life challenged by oxygen-poor ocean -- Geochemists from the University of California, Riverside and their colleagues from Virginia, Canada and France have analyzed the chemistry of the ancient oceans between 1.8 billion to 0.8 billion years ago and how this chemistry affected early marine organisms. Based upon their tracking of a variety of elements including chromium and molybdenum, they found that during this one-billion year interval oxygen levels in the ancient oceans were generally low. The low oxygen levels meant that marine life was dominated by bacteria rather than diverse and large populations of more complex organisms. This general lack of complex life organisms during this interval have led some scientists to label it the "the boring billion." [University of California, Riverside Today]
• Mass extinction at end of Triassic triggered by huge volcanic eruptions -- Researchers at the Massachusetts Institute of Technology (MIT) and colleagues from other research institutions claim that numerous huge volcanic eruptions occurred at approximately 200 million years ago, which was at the same time as a massive extinction that decimated 76 percent of marine and terrestrial species of life. This mass extinction marks the end of the Triassic geologic period and the onset of the Jurassic, during which dinosaurs flourished during the next 135 million years. The massive volcanic eruptions from a large region known as the Central Atlantic Magmatic Province (CAMP) over a 40,000-year span at the end of the Triassic appear to have triggered the mass extinction as the atmospheric carbon dioxide levels rose, which caused acidification of the oceans and increased global temperatures. [MIT News]
• 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, drought, floods, 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, to include 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. 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.

Historical Events:

• 25 March 2000...A rouge wave near Shelter Cove, CA swept a lady from a Canadian school group into the ocean. Four members of the group tried to rescue her, but were overcome by the waves and currents. A fishing vessel and the US Coast Guard rescued two of the rescuers. (Accord's Weather Guide Calendar)
• 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)
• 26-28 March 2004…The first ever confirmed hurricane in the South Atlantic Ocean, named Catarina, struck the coast of the Brazilian states of Santa Catarina and Rio Grande do Sul with heavy rains and winds, before dissipating over land late on the 28th. (The Weather Doctor)
• 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 were 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)
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Prepared by AMS DS Ocean Central Staff and Edward J. Hopkins, Ph.D., email hopkins@meteor.wisc.edu
© Copyright, 2013, The American Meteorological Society.