Weekly Ocean News

WEEKLY OCEAN NEWS

DATASTREME OCEAN WEEK THREE: 17-21 September 2007

Ocean in the News

(Thurs.) Thin Arctic sea ice is reported -- An expedition to the North Polar Sea by an international team of scientists aboard the Research Ship Polarstern from the Alfred Wegener Institute for Polar and Marine Research reports thin Arctic sea ice of approximately one meter thickness, which represents a 50-percent thinning of the ice compared with six years ago. Oceanographic buoys were deployed. [Alfred Wegener Institute for Polar and Marine Research] Instruments onboard the European Space Agency's Envisat satellite also have detected the smallest areal extent of Arctic sea ice. [ESA]
(Thurs.) Mathematics applied to melting of polar ice-- Mathematicians from the University of Utah have been developing mathematical models designed to study the permeability of sea ice to saltwater in an effort to understand the effect of higher temperatures upon the melting of the polar icepack. [EurekAlert!]
(Tues.) "Mission to Aquarius" to study Florida reefs -- A team of scientists and educators participating in NOAA's National Marine Sanctuary Program will start a nine-day mission called "Aquarius 2007: If Reefs Could Talk" on Monday that will take them to the Aquarius undersea lab, the world’s only undersea scientific facility, below the surface waters of the Florida Keys National Marine Sanctuary. This mission, designed to study corals and marine life, can be tracked by students and the pubic through the OceansLive.org education Web portal. [NOAA News]
(Tues.) Green in the Red Sea -- An image of the surface water of the Red Sea obtained from the Sea-viewing Wide Field-of-View Sensor (SeaWiFS) shows chlorophyll from phytoplankton, single cell marine plants that accumulated in several large patches. [NASA Earth Observatory]
(Tues.) Starving whales could mean depleted ocean -- Researchers with Stanford University and the University of Washington report that based upon their genetic studies, the number of gray whales in the eastern North Pacific remains well below historic levels, indicating that these whales may be starving, potentially caused by problems in the food chain as the oceans become depleted. [EurekAlert!]
(Tues.) A glimpse at ancient whales -- Paleontologists at the University of California, Berkley discovered and are studying an ancient "whale fall" with an ancient whale fossils from California's Año Nuevo Island that they date between 11 million to 15 million years ago. [EurekAlert!]
Eye on the tropics -- During the last week several tropical cyclones (low pressure systems that form over tropical or subtropical oceans) developed and moved across tropical waters:
- In the western Gulf of Mexico, a tropical depression developed rapidly into Tropical Storm Humberto, the eighth named tropical cyclone of the 2007 North Atlantic hurricane season North Atlantic, early last week. As it moved to the northeast, it intensified to a Category 1 hurricane (on the Saffir-Simpson Scale) just before making landfall along the upper Texas Gulf coast early last Thursday. Humberto represented the third hurricane of the season in the North Atlantic basin. A MODIS image from the NASA Terra satellite showed the clouds surrounding Tropical Storm Humberto before it became a hurricane. [NASA Earth Observatory] A subsequent image from NOAA's GOES-12 satellite shows Humberto after it made landfall. [NOAA OSEI]
  A tropical depression formed in the central tropical Atlantic at midpoint of last week and eventually became Tropical Storm Ingrid, the ninth named tropical cyclone of the 2007 North Atlantic hurricane season, at the end of the week. Over the weekend, this minimal tropical storm weakened and was reclassified as a tropical depression as it approached the northern Leeward Islands. An image from the GOES-12 satellite shows the clouds associated with Tropical Storm Ingrid at the end of last week. [NOAA OSEI]
- In the western North Pacific, a typhoon (the western North Pacific equivalent of a hurricane) called Nari formed near early last week to the east-southeast of Taiwan and moved to the northwest and then to the north toward South Korea. It became a supertyphoon near the end of the week as maximum sustained winds exceeded 140 mph. By late Sunday (local time), Nari had made landfall in South Korea and quickly weakened to a tropical storm. A MODIS image from NASA's Terra satellite shows the clouds surrounding Typhoon Nari. [NASA Earth Observatory] A later satellite image from the Japanese MTSAT satellite shows the typhoon near Okinawa. [NOAA OSEI]
  Another typhoon, called Wipha, formed to the northeast of the Philippine island of Luzon on Saturday (local time) and moved to the northwest. As of Monday (local time), it was a minimal typhoon as it moved toward China.
Flooding from a typhoon -- A pair of images obtained from the MODIS instrument on NASA's Aqua satellite taken nearly two weeks apart over a region of Japan to the north of Tokyo before and after the landfall of Typhoon Fitow reveals the extent of the flooding caused by that typhoon. [NASA Earth Observatory]
Corals place on an endangered list -- A exhaustive study of marine life conducted by the Conservation International (CI) and the IUCN (World Conservation Union) of coral in waters surrounding the Galapagos Islands has led the IUCN to place three species of corals unique to these islands on the IUCN Red List of Threatened Species since these coral soon could become extinct. [EurekAlert!]
New Jersey beaches closed because of medical waste and trash -- The New Jersey Department of Environmental Protection was forced to close several state beaches over the recent Labor Day weekend because medical waste and other trash had washed onto the shore. These beaches have since been reopened. [US Water News Online]
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.

THE AUTUMNAL EQUINOX -- The Autumnal Equinox will occur early next Sunday morning (officially at 0951Z, 23 September 2007 or 5:51 AM EDT or 4:51 PM CDT, etc.). At that time the noontime sun will appear directly above the equator, representing one of the two times during the year for such an occurrence, with the other being at the vernal equinox in March. The term "equinox" arises from the fact that this time of year represents "equal night" and equal day essentially everywhere. Within the subsequent several days, the length of daylight will become noticeably shorter. This decrease in daylight will continue for another three months to the winter solstice early Saturday, 22 December 2007.

Editor's note: John White, a meteorologist from North Carolina involved with the AMS Education program, reported that the geosynchronous (or geostationary) satellites make an "satellite eclipse" of the sun near the spring and autumnal equinoxes because of their equatorial orbit, such that these satellites pass through the earth's shadow and the satellite is powered down when the solar array does not receive sufficient sunlight. [For more information, consult NWS Southern Region GOES Satellite FAQ] EJH.

Concept of the Week: Sea Water Salinity and Carbon Dioxide

In view of the contemporary concern regarding global climate change, scientists are studying the various factors that govern the ocean's ability to absorb atmospheric carbon dioxide. Concentrations of atmospheric carbon dioxide are on the rise primarily because of the burning of fossil fuels (i.e., coal, oil, natural gas). Carbon dioxide is a greenhouse gas (an atmospheric gas that absorbs and radiates infrared radiation) so that higher levels of atmospheric carbon dioxide may be contributing to global warming. The ocean's role in regulating the concentration of atmospheric carbon dioxide depends on the temperature, salinity, and biological components of surface waters.

As noted in Chapter 3 of your textbook, gases are more soluble in cold seawater than warm seawater. Hence, changes in sea surface temperature affect the ability of the ocean to absorb carbon dioxide. As noted in Chapter 1 of your textbook, photosynthetic organisms take up carbon dioxide and release oxygen. And through cellular respiration, all organisms release carbon dioxide. What about the effects of changes in salinity on the ocean's uptake of atmospheric carbon dioxide? Research from the Pacific Ocean near Hawaii provides some insight on this question.

Since the late 1980s, scientists have been recording ocean conditions at a site (dubbed ALOHA) about 100 km (62 mi) north of Oahu. In 2003, David M. Karl, a biogeochemist at the University of Hawaii in Honolulu, reported a decline in the rate at which surface ocean waters were absorbing carbon dioxide from the atmosphere. In fact, in 2001, the rate of CO₂ uptake was only about 15% of what it was in 1989. Why the change in CO₂ uptake? In this region of the Pacific north of Hawaii, sea surface temperatures showed no significant change during the period of observation but precipitation decreased and evaporation increased. Less precipitation coupled with higher rates of evaporation caused the surface water salinity at ALOHA to increase by about 1%. Increasing salinity inhibits water's ability to absorb gases including carbon dioxide. Karl and his colleagues attribute 40% of the decline in the ocean's CO₂ uptake to the saltier waters. The balance of the decline may be due to changes in biological productivity or ocean mixing

Concept of the Week: Questions

With rising sea surface temperatures, the rate of evaporation of sea water [(increases)(decreases)].
With increasing salinity and constant temperature, the amount of atmospheric carbon dioxide that is taken up by ocean water [(increases)(decreases)].

Historical Events

17-23 September 1989...Hurricane Hugo hit the Virgin Islands on the 17^th, producing wind gusts to 97 mph at Saint Croix. Hurricane Hugo passed directly over the island of Saint Croix causing complete devastation and essentially cutting off the island's communications systems. A storm surge of five to seven feet occurred at Saint Croix. The only rain gauge left operating, at Caneel Bay, indicated 9.40 in. in 24 hrs. Hurricane Hugo claimed the lives of three persons at Saint Croix, and caused more than $500 million in damage. A ship, Nightcap, in the harbor of Culebra, measured wind gusts as high as 170 mph. On the 18^th, Hugo hit Puerto Rico, producing a storm surge of four to six feet, and northeastern sections of the island were deluged with more than ten inches of rain. Hugo claimed the lives of a dozen persons in Puerto Rico, and caused $1 billion in property damage, including $100 million in crop losses. On the 21^st, Hugo slammed into the South Carolina coast at about 11 PM, making landfall near Sullivans Island. Hurricane Hugo was directly responsible for thirteen deaths, and indirectly responsible for twenty-two others. A total of 420 persons were injured in the hurricane, and damage was estimated at $8 billion including $2 billion damage to crops. Sustained winds reached 85 mph at Folly Beach SC, with wind gusts as high was 138 mph. Wind gusts reached 98 mph at Charleston, and 109 mph at Shaw AFB. The highest storm surge occurred in the McClellanville and Bulls Bay area of Charleston County, with a storm surge of 20.2 ft reported at Seewee Bay. Shrimp boats were found one half-mile inland at McClellanville. On the 22^nd, Hugo quickly lost strength over South Carolina, but still was a tropical storm as it crossed into North Carolina, just west of Charlotte, at about 7 AM. Winds around Charlotte reached 69 mph, with gusts to 99 mph. Eighty percent of the power was knocked out to Charlotte and Mecklenburg County. Property damage in North Carolina was $210 million and damage to crops was $97 million. The greatest storm surge occurred along the southern coast shortly after midnight, reaching nine feet above sea level at Ocean Isle and Sunset Beach. Hugo killed one person and injured fifteen others in North Carolina. (Storm Data) (The National Weather Summary)
17 September 1996…Remnants of Hurricane Fausto that had initially formed over the eastern Pacific and moved northeastward from Mexico reformed into a powerful coastal storm in Atlantic waters off the Del-Mar-Va Peninsula, before passing Cape Cod in eastern Massachusetts. Winds gusted to 50 mph and rainfall was up to four inches. Minor coastal flooding in the New York City metropolitan area. (Accord Weather Guide Calendar)
18 September 1926...The great "Miami Hurricane" produced winds reaching 138 mph, which drove ocean waters into Biscayne Bay drowning 135 persons. The eye of the hurricane passed over Miami, at which time the barometric pressure dropped to 935.0 millibars (27.61 inches of mercury). Tides up to twelve feet high accompanied the hurricane, which claimed 372 lives. (David Ludlum) (The Weather Channel)
19 September 1957...Bathyscaph Trieste, in a dive sponsored by the Office of Naval Research in the Mediterranean, reached a record depth of 2 miles. (Naval Historical Center)
19 September 1967...Hurricane Beulah deluged Brownsville, TX with 12.19 in. of rain in 24 hrs, to establish a record for that location. Hurricane Beulah made landfall on the 20^th near the mouth of the Rio Grande River, where a wind gust of 135 mph was reported by a ship in the port. (19^th-20^th) (The Weather Channel)
20 September 1909...A strong hurricane made landfall in southeastern Louisiana. A 15-ft storm surge flooded the Timbalier Bay area. Some 350 people perished. (Intellicast)
21 September 1938...The "Great New England Hurricane" smashed into Long Island and bisected New England from New Haven, CT across Massachusetts and Vermont, causing a massive forest blowdown and widespread flooding. Winds gusted to 186 mph at Blue Hill Observatory in Milton, MA, and a storm surge of nearly 30 ft caused extensive flooding along the coast of Rhode Island. The hurricane killed over 600 persons and caused $500 million damage. The hurricane, which lasted twelve days, destroyed 275 million trees. Hardest hit were Massachusetts, Connecticut, Rhode Island, and Long Island NY. The "Long Island Express" produced gargantuan waves with its 150 mph winds. Waves smashed against the New England shore with such force that earthquake-recording machines on the Pacific coast clearly showed the shock of each wave. (David Ludlum) (The Weather Channel)
20 September 1519...Portuguese navigator Ferdinand Magellan set sail from Spain in an effort to find a western sea route to the rich Spice Islands of Indonesia. In October 1520, he passed through the straits that now bear his name separating Tierra del Fuego and the South American mainland and became the first known European explorer to enter the Pacific Ocean from the Atlantic. In September 1522 one remaining ship from the original five that set sail returned to Spain, to become the first ship to circumnavigate the globe. Magellan was killed in the Philippines in 1521. (The History Channel)
22-23 September 1998...Hurricane Georges raked Hispaniola leaving over 580 dead in Haiti and the Dominican Republic, due mainly to flash flooding and subsequent mud slides in high terrain regions. Damage estimates from the storm exceeded $1 billion (US). (The Weather Doctor)
23 September 1551...The Grand Harbour at Valetta, Malta was hit by a waterspout that then moved inland and caused extensive damage. A shipping armada in the harbor about to go into battle was destroyed by the waterspout killing at least 600 people. (The Weather Doctor)
23 September 1815...One of the most powerful hurricanes to strike New England made landfall initially on Long Island, NY and then again at Old Saybrook, CT before crossing into Massachusetts and New Hampshire. Extensive structural damage resulted. Providence, RI was flooded and six people were killed. This "Great September Gale" was the worst tempest in nearly 200 years, equal in strength to the Great 1938 Hurricane, and one of a series of severe summer and autumn storms to affect shipping lanes that year. (David Ludlum)