DATASTREME OCEAN WEEK THREE: 20-24 September 2004

• Recent tropical weather systems are deadly:
• Remnants of Hurricane Ivan moved northward along the Appalachians at the end of last week spreading flooding rain and spawning tornadoes. As of Saturday, Ivan was responsible for the deaths of at least 25 people in the US. Earlier, 60 fatalities were reported across the Caribbean islands as a result of the hurricane that had reached Category 5 on the Saffir-Simpson Hurricane Intensity Scale. [CNN]
• Another tropical system has also proven to be deadly. As of Saturday, nine people had died as a result of Tropical Storm Jeanne, which moved along the coast of the Dominican Republic late last week before heading out across the western Atlantic toward the Bahamas over the weekend. [CNN]
• The Big Easy dodged another one -- Hurricane Ivan passed sufficiently far to the east of New Orleans that the Crescent City was able to survive major flooding and other storm damage. Much of the city that lies between the Mississippi River and Lake Pontchartrain is below sea level and depends upon pumps to keep the city dry. [USA Today]
• Changes in Antarctic ice sheet and Southern Oceans linked -- After analyzing the oceanic temperature and ice sheet history derived from deep sea sediments, scientists at the University of California, Santa Barbara claim that the rapid growth of the Antarctic ice sheets approximately 14 million years ago appears to be related changes in temperature, ocean circulation and carbon cycling in the Southern Oceans. [EurekAlert!]
• Algae could trigger coral disease -- A group of scientists recently reported that increased abundance of seaweed, a macroalgae, coming in contact with reef-building coral species could spread disease in the coral species and result widespread decline in coral reefs. [EurekAlert!]
• Rare whale found -- In July, a paleontology graduate student from South Dakota Schools of Mines and Technology found a rare 13-foot Sowerby's beaked whale that was beached on St. Catherine's Island off the coast of Georgia. [EurekAlert!]
• New generation European weather satellite unveiled -- The European Space Agency put their Meteosat-8 into operation last week, marking the first Meteosat Second Generation meteorological satellite, a geosynchronous satellite that has a variety of highly sophisticated sensors, to include the Geostationary Earth Radiation Budget (GERB) instrument that provides quantitative measurements of the solar and terrestrial radiation components in the planetary energy budget. [ESA]
• Earthweek -- Diary of the Planet [earthweek.com] Requires Adobe Acrobat Reader.

THE AUTUMNAL EQUINOX -- The Autumnal Equinox will occur midday on Wednesday, 22 September (at 1630Z, or 12:30PM EDT or 11:30 AM 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 next several days, the length of daylight will become noticeably shorter. This decrease in daylight will continue for another three months to the winter solstice on Tuesday, 21 December 2004.

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 could lead 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? Recent research from the Pacific Ocean near Hawaii provides some insight.

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

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

• 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 dollars 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 two hundred 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)
• 24 September 1493...Christopher Columbus set sail with 17 ships on his second expedition to the New World, reaching the Lesser Antilles, the Virgin Islands, Puerto Rico and Hispaniola before returning to Europe in March 1496. (Wikipedia)
• 25 September 1513... Vasco Núñez de Balboa, a Spanish conquistador-explorer, crossed the isthmus of Panama and reached the Pacific Ocean, which he christened Mar del Sur (South Sea), claiming the ocean and all adjacent lands for Spain. (Wikipedia)
• 25 September 1939...A West Coast hurricane moved onshore south of Los Angeles bringing unprecedented rains along the southern coast of California. Nearly 5.5 in. of rain drenched Los Angeles during a 24-hr period. The hurricane caused $2 million in damage, mostly to structures along the coast and to crops, and claimed 45 lives at sea. "El Cordonazo" produced 5.66 in. of rain at Los Angeles and 11.6 in. of rain at Mount Wilson, both records for the month of September. (David Ludlum) (The Weather Channel)
• 25 September 1956...The world's first transatlantic telephone cable system began operating (Clarenville, Newfoundland to Oban, Scotland). Previous cables had been limited to telegraph transmissions. (Today in Science History)
• 26 September 1580...English seaman Francis Drake returned to Plymouth, England, in the Golden Hind, becoming the first British navigator to circumnavigate the globe. He had commenced his voyage around the world on 13 December 1577 with five ships, but returned with only one ship. During his voyage in the Pacific Ocean, he paused near San Francisco Bay and then traveled as far north as present-day Washington State. He brought back valuable information about the world's ocean to Queen Elizabeth I. (The History Channel)
• 26-27 September 1959...Typhoon Vera ravaged Honshu, Japan, the nation's largest island, leaving over 5000 dead, more than 40,000 injured, 1.5 million homeless and 40,000 homes destroyed. It was Japan's greatest storm disaster. (The Weather Doctor)

Return to DataStreme Ocean Homepage

URL: DSOcean:/news.html
Prepared by AMS DSOcean Central Staff and Edward J. Hopkins, Ph.D., email hopkins@meteor.wisc.edu
© Copyright, 2004, The American Meteorological Society.