Weekly Ocean News

WEEK EIGHT: 26-30 October 2009

Items of Interest:

Opportunity for Teachers: The National Ocean and Atmospheric Administration's (NOAA) Teacher at Sea 2010 Field Season program is now accepting applications until 31 December 2009. 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 --Organized tropical weather activity was relatively light this past week across the major ocean basins of the Northern Hemisphere:
- No organized tropical cyclone activity occurred during this past week in the North Atlantic basin.
- In the eastern North Pacific basin, Hurricane Rick, which had become the second strongest hurricane in this basin in the last half century last weekend, turned toward the northeast and made landfall along the central coast of mainland Mexico at midweek, after weakening to a tropical storm. A classic image of Hurricane Rick was made from data collected from the MODIS sensors on NASA's Terra satellite when Rick was a category-5 hurricane (on the Saffir-Simpson Scale). [NASA Earth Observatory] Additional images and information on Hurricane Rick appear in NASA Hurricane Page.
- In the central North Pacific, Hurricane Neki, the second named tropical cyclone of 2009 to form in that basin, developed at the start of last week approximately 700 miles south of Hawaii's Big Island. During the week, this hurricane traveled westward and then northwestward and northward, intensifying into a major category 3 hurricane. Over this past weekend, Neki weakened was downgraded to a tropical storm as it traveled northward several hundred miles west of the Hawaiian island of Kauai. For more information including satellite images concerning hurricane Neki, consult the NASA Hurricane Page.
- In western North Pacific Typhoon Lupit, which had become a major category-4 typhoon last weekend, continued to travel west to near the northeastern coast of the Philippine island of Luzon early last week. Weakening to a tropical storm, Lupit abruptly turned to take a northward and northeastward track, passing to the east of Taiwan late week. An image of the near surface winds surrounding the typhoon was obtained from data collected by the scatterometer instrument onboard NASA' QuikSCAT satellite. [NASA Earth Observatory] The NASA Hurricane Page has additional satellite images and information on Lupit.
Public comment needed for sonar operations off the Marianas -- NOAA’s Fisheries Service is seeking public comments through mid-November on a proposed rule designed to minimize the impact that sonar operations conducted by the US Navy in the waters off the coast of the Mariana Islands would have on marine mammals. [NOAA News]
"Back home again in Indiana" for "NOAA Teacher at Sea"-- Christine Hedge, a seventh-grade science teacher from Carmel Middle School in Carmel, IN recently returned home to her students after spending six weeks in the Arctic Ocean on board the U.S. Coast Guard icebreaker Healy as "NOAA Teacher at Sea." She was part of a multi-agency effort designed to collect seafloor mapping and oceanographic data along the North American Extended Continental Shelf. [NOAA News]
New PORTS® system installed to improve safety for marine interests at Port of New Orleans -- A new ocean observing system, the NOAA Physical Oceanographic Real-Time System (PORTS®) has been installed on the lower Mississippi River near the Port of New Orleans (LA) that collects observations of tides, currents, water and air temperature, barometric pressure, winds and bridge clearance from a variety of sensors in and around the port. This system is meant to ensure ship captains and pleasure boaters with real-time free observations designed to increase maritime safety and efficiency. [NOAA News]
Precipitation patterns during El Niño and La Niña events -- Images were assembled too show the differences in the sea surface temperatures and the precipitation across the Pacific Ocean Basin and the Americas from their respective long-term averages during major El Niño and La Niña events (December 1997 and December 1998, respectively) from NOAA’s Advanced Very High Resolution Radiometer and from the Global Precipitation Climatology Project's blended rainfall data collected by several satellites. El Niño and La Niña events are associated with anomalous large-scale atmospheric and oceanic circulation patterns. [NASA Earth Observatory]
Studying causes of coral bleaching -- Researchers from the National Institute of Standards and Technology and five other institutions have been using sophisticated technology to study the metabolic activity of a pathogen that has been shown to cause coral bleaching, which represents a serious threat to undersea reef ecosystems. [EurekAlert!]
Model developed to predict hurricane-related power outages -- Researchers at Johns Hopkins and Texas A&M Universities have developed a risk analysis computer model that accurately predicts power outages in a region in advance of an approaching hurricane. [EurekAlert!]
Planetary seismic noise could improve hurricane time series reconstruction -- Seismologists from Northwestern and Clemson Universities used digital seismograms dating through the 20th century from monitoring stations in Massachusetts and Puerto Rico to improve the time series of North Atlantic hurricanes especially prior to the era of satellite surveillance. [Geological Society of America]
New delta land could be built by cutting Mississippi levees -- Researchers at the University of Texas in Austin propose that cutting holes in levees along the Mississippi River below New Orleans so as to divert some of the river could produce nearly half as much new land in the river's delta from suspended sediments annually as is lost due to sinking of the land. [EurekAlert!]
Building a rogue wave -- Physicists at the Australian National University using a model developed for optics to arrive at a possible theory for the sudden development of rogue waves in the ocean, in which small peaks called "breathers" suddenly appear and then disappear in one spot, possibly seeding the rogue waves. [EurekAlert!]
Saving the beach sand -- A seven-year study conducted by the US Geological Survey in collaboration with the South Carolina Sea Grant Consortium designed to improve projections of coastal change has resulted in a model for beach preservation that involves determination of those geologic features and ocean processes that keep the sand from washing away. [USGS Newsroom]
Annual Arctic Report Card handed out -- NOAA's Climate Program Office recently released the 2009 annual update of the Arctic Report Card, a report of the state of the air, ocean and ice in the Arctic basin prepared by 71 national and international scientists. These experts have found that drastic changes in the region have occurred within the last five years, with 2009 having slightly more summer sea ice than during the two previous years. [NOAA News]
Arctic sediments reveal unprecedented changes in last century -- Analysis of sediments from the Arctic retrieved by University at Buffalo geologists and colleagues indicated that the changes recorded by these sediments during the last 50 years are unprecedented when compared with other previous warming episodes during the last 200,000 years. [University at Buffalo]
Exploring the oldest known submerged town -- Marine archaeologists from Greece and the United Kingdom have discovered of late Neolithic pottery in waters of the Mediterranean Sea off the southern Laconia coast of Greece, which appear to make the ancient port city of Pavlopetri, the oldest submerged community, dating back to between 5000 and 6000 years ago. [EurekAlert!]
Loss of West Antarctic ice sheet may be slower than thought -- Analysis of data collected by the West Antarctic GPS Network project has led researchers from the University of Texas at Austin, Ohio State University, and the University of Memphis suggest that the rate of ice loss from the West Antarctic ice sheet has not been as fast as previously thought. [EurekAlert!]
Potential Australian seabed response to climate change studied -- Scientists at Australia's Commonwealth Scientific and Industrial Research Organisation have conducted a five-year study designed to predict potential high-risk areas in the seabed surrounding Australia due climate change in addition to seabed movement, erosion and changes in reef growth. [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: 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

The most important factor contributing to erosion of Louisiana's coastal wetlands is [(saltwater intrusion)(levees along the banks of the Mississippi River)].
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:

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)
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)