WEEK EIGHT: 25-29 October 2010

Items of Interest:

• Opportunity for Teachers:
The National Ocean and Atmospheric Administration's (NOAA) Teacher at Sea 2011 Field Season program is now accepting applications until 30 November 2010. 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:

• Eye on the tropics --
Several organized tropical cyclones were found across the major ocean basins of the Northern Hemisphere during the last week:
• In the North Atlantic basin, Tropical Storm Richard, the seventeenth named tropical cyclone of the 2010 hurricane season, formed from a tropical depression over the western Caribbean Sea late last week. This tropical storm moved westward and brushed the coast of Nicaragua and Honduras during the early morning hours of Sunday. By late Sunday morning, Tropical Storm Richard moved across to the west-northwest toward Belize and became the tenth hurricane of 2010 as maximum sustained surface winds strengthened to 85 mph. [USA Today] Satellite images and additional information on Richard appear in NASA Hurricane Page.
• In western North Pacific basin, Typhoon Megi, which had become a supertyphoon (roughly equivalent to a category 5 hurricane on the Saffir-Simpson Scale) during the previous week over the Philippine Sea, reached the traveled northern Luzon in the Philippines at the start of this past week. Moving across Luzon, Megi had weakened to a category 2 typhoon before curving to the north. Megi traveled across the South China Sea toward the coast of southeast China. After briefly intensifying to a category 3 system, Megi began weakening and was reclassified as a tropical storm as it approached the Taiwan Strait and the China coast. Some casualties associated with Megi were reported in Taiwan. [USA Today] See the NASA Hurricane Page for additional information and satellite images on Megi.
  Two other tropical depressions formed last week over the western North Pacific. Tropical Depression 16 moved across the waters southeast of Kadena, Japan. See the NASA Hurricane Page for more information on TD 16W. The other system, Tropical Depression 17 formed northeast of Saipan. The NASA Hurricane Page has a satellite image and additional information on TD 17 W.
• In the North Indian Ocean Basin, Tropical Cyclone Giri formed late last week over the Bay of Bengal to the southeast of Myanmar (Burma) and intensified to a category 4 cyclone on the Saffir-Simpson Hurricane Scale. By early Saturday, Giri made landfall along the coast of Myanmar. [USA Today] For additional information along with satellite imagery on this cyclone, consult the NASA Hurricane Page.
• Annual Arctic Report Card handed out --
NOAA's Climate Program Office recently released its 2010 annual update of the Arctic Report Card, a report of the state of the air, ocean and ice in the Arctic basin prepared by an international team of 69 scientists, including those from NOAA. These experts have found that the region continues to warm at an unprecedented rate in 2010, with record temperatures in Greenland, record decreases in Arctic snow cover and a thinning of Arctic sea ice, together with a reduced areal coverage in the summer sea ice. The scientists caution that these events could result in dramatic changes in the weather patterns elsewhere across the Northern Hemisphere. [NOAA News]
• More Gulf waters are reopened --
At the end of last week, NOAA reopened more than 7000 square miles of Gulf of Mexico waters off the Florida Panhandle to commercial and recreational fishing, after following consultation with officials from the US Food and Drug Administration and the Gulf Coast States. Currently, 96 percent of federal waters are open following the Deepwater Horizon BP oil spill. [NOAA News]
• Rehabilitated sea turtles returned to Gulf waters --
Last week, scientists from NOAA, the Louisiana Department of Wildlife and Fisheries and the Audubon Nature Institute along with assistance from the US Coast Guard returned 32 rehabilitated sea turtles to Gulf of Mexico waters offshore of Louisiana, approximately three months after being rescued from the oil spill. [NOAA News]
• Population of spotted seals placed on threatened list --
Although the southern distinct population segment of the spotted seal is located in areas outside the jurisdiction of the United States, NOAA recently listed this population as being threatened under the Endangered Species Act, meaning that this agency can strictly regulate importation of the animal or its parts into the country. In addition, Americans would be prohibited from taking this animal whose population is centered in northeast China's Liaodong Bay, an arm of the Yellow Sea, and eastern Russia's Peter the Great Bay, a gulf in the Sea of Japan. [NOAA News]
• Draft management plan for a national marine sanctuary released for public review --
At the end of last week, NOAA officials released for public review and comment a draft management plan and environmental assessment for the agency's Flower Garden Banks National Marine Sanctuary that is located in the waters of the Gulf of Mexico off the Texas and Louisiana coasts. [NOAA News]
• Dam is breached to restore stream health in Maryland --
The Simkins Dam on Maryland's Patapsco River recently was breached, which opened approximately 20 miles of stream habitat along this river and its tributaries. NOAA's Fisheries Service and local partners celebrated the breaching of this dam as an opportunity to restore the health of this river and Chesapeake Bay, the nation's largest estuary, into which the Patapsco River flows. [NOAA News]
• Microbial consumption of oil-spill waste is a surprise --
Researchers at Harvard University, the University of Georgia, the U.S. Naval Research Laboratory, the Monterey Bay Aquarium Research Institute and Stanford University have found that microbes living in the bottom waters of the Gulf of Mexico may have consumed more oil spilled into the Gulf from the Deepwater Horizon oil spill than previously thought. [EurekAlert!]
• Sea-level rise measured in the Falklands --
Using sea level measurements from 1842 and from the last 30 years, researchers at the United Kingdom's National Oceanography Centre have found that the sea level of the South Atlantic around the Falkland Islands has increased since the mid-nineteenth century. Furthermore, the rate of in the sea-level rise has accelerated over the last several decades. This long-time series in sea level measurements in the Falklands is needed to assess the role that increasing global temperatures would have on global sea level. [National Oceanography Centre]
• Feasibility studies made of wind farms offshore of the Del-Mar-Va Peninsula --
In a study conducted by the University of Maryland's Center for Integrative Environmental Research, wind farms placed 12 to 40 miles off the coast of the Del-Mar-Va Peninsula appears to be a reasonable means for Maryland to meet its renewable energy goals, but some economic and political hurdles remain. [University of Maryland]
• 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: Loss of Louisiana's Coast

According to the Louisiana Coastal Wetlands Conservation and Restoration Task Force, Louisiana has been losing its coastal wetlands (bayous, marshes, and swamps) to the waters of the Gulf of Mexico at an alarming rate of about 65 to 100 square km (25 to 38 square mi) per year for the past several decades. This loss adversely affects fisheries in the Gulf of Mexico and makes the coastal zone more vulnerable to storm surges such as that produced by Hurricane Katrina in August 2005. Since the early 1930s, the state's coastal wetlands have shrunk by an area equivalent to the state of Delaware. According to USGS estimates, an additional 1800 square km (700 square mi) could be lost by mid-century. The price tag for reversing this trend, restoring some marshes, and protecting the remaining 15,000 square km (5800 square mi) of wetlands could top $14 billion and take decades to complete. Many people argue that the value of Louisiana's coastal wetlands is well worth the expense.

As much as 75% of the fish and other marine life in the northern Gulf of Mexico depend on Louisiana's coastal wetlands. The wetlands are a nursery for commercially important catches of shrimp, crawfish, blue crab, and oysters. It is a food source for larger fish including yellow fin tuna, red snapper, and swordfish. In 2003, about three-quarters of the nation's fish and shellfish catch by weight came from Louisiana's waters. In addition, the wetlands are a stopover for millions of birds migrating between North and Central/South America. Furthermore, wetlands and associated barrier islands protect the ports, buildings, and other coastal zone structures from storm surges. Wetlands are particularly important in buffering the levees surrounding New Orleans, much of which is below sea level.

Many factors contribute to the loss of Louisiana's coastal wetlands. Thousands of kilometers of pipelines transporting oil and natural gas through the marshes plus the extensive network of navigation channels allow saltwater to intrude the wetlands. Increased salinity of the originally fresh or brackish waters kill wetland grasses, shrubs, and other vegetation that anchor soil in place. The canals also allow tidal currents to flow farther inland, accelerating erosion of wetland soils. The most important factor, however, is the consequence of flood control structures (levees) constructed along the banks of the Mississippi River. Levees constrict the flow of the river so that waters and suspended sediment discharge rapidly into the Gulf. Deprived of a continuous input of sediments and vegetation-supporting nutrients, existing sediments compact, wetlands subside and Gulf waters invade the wetlands. With the anticipated continued rise in sea level due to global climate change (discussed in Chapter 12 of your textbook), erosion of Louisiana's coastal wetland may accelerate in the future.

Plans to reverse the loss of Louisiana's coastal wetlands (the Coast 2005 plan and the Louisiana Coastal Area plan) seek to restore the structure and function of coastal wetlands. One proposal is to breach some levees along the lower Mississippi. This partial diversion of the Mississippi would increase the supply of sediments to the wetlands. Closing or installing locks on some navigation canals would reduce saltwater intrusion. In addition, dredged sediment would be used to re-build wetlands and restore barrier islands.

Concept of the Week: Questions

1. The most important factor contributing to erosion of Louisiana's coastal wetlands is [(saltwater intrusion)(levees along the banks of the Mississippi River)].
2. Global climate change that is accompanied by a rise in sea level is likely to [(accelerate)(have no effect on)] the rate of erosion of Louisiana's coastal wetlands.

Historical Events:

• 25 October 1859...The Royal Charter Storm, named after the loss of the fully rigged ship Royal Charter off the coast of Anglesey, England, drowned about 500 people, along with the loss of gold bullion. The ship was one of over 200 vessels wrecked between 21 October and 2 November, with the loss of around 800 lives. This tragedy led to the introduction of gale warnings in June 1860. (The Weather Doctor)
• 25 October 1941...South Greenland Patrol expanded to include three cutters of the Northeast Greenland Patrol and form the Greenland Patrol. (USCG Historian's Office)
• 25-26 October 1980...The combination of unusually high tides and southeasterly winds gusting to 75 mph generated waves with heights to 25 ft, resulting in serious flooding, beach erosion and sea wall damage along the Maine coast. Wind damage was considerable and as many as 100,000 homes were without power for up to 40 hrs. (Accord Weather Guide Calendar)
• 27 October 1728...Captain James Cook, the famed British naval officer who was one of the first of the scientific navigators, was born on this date. Captain Cook surveyed the coasts of Labrador and Newfoundland before making three expeditions into the Pacific Ocean where he became the first Englishman to explore previously uncharted locations. On his various voyages, he conducted astronomical observations and his ship's botanist studied the flora and fauna that were collected. (Today in Science History)
• 28 October 1492...The famous Italian explorer, Christopher Columbus, landed on Cuba. (Wikipedia)
• 28 October 1991...Typhoon Thelma devastated the Philippines. Reports indicated that 6000 people died by catastrophic events related to the storm including dam failure, landslides, and extensive flash flooding. The greatest number of casualties occurred on Leyte Island where an 8-ft storm surge struck Ormoc, accounting for over 3000 fatalities. (The Weather Doctor)
• 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)

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Prepared by AMS DS Ocean Central Staff and Edward J. Hopkins, Ph.D., email hopkins@meteor.wisc.edu
© Copyright, 2010, The American Meteorological Society.