Weekly Ocean News

WEEKLY OCEAN NEWS

WEEK THREE: 15-19 September 2008

Ocean in the News

Eye on the tropics -- During the last week several tropical cyclones (low pressure systems that form over tropical or subtropical oceans) developed and traveled across tropical waters of the major ocean basins of the Northern Hemisphere:
- In the North Atlantic basin, Hurricane Ike, which had reached category 4 status on the Saffir-Simpson Intensity Scale on the previous weekend as it traveled across the southeastern Bahamas in southwestern Atlantic, weakened after making landfall along the northeastern coast of Cuba. After crossing Cuba, it had weakened to a minimal category 1 hurricane before it re-intensified to a strong category 2 system after entering the Gulf of Mexico late in the midweek. On early Saturday morning, Ike made landfall on the upper Texas Gulf coast near Galveston. Ike weakening to a tropical storm and then to a tropical depression by early Sunday, over southwestern Arkansas. An image from the MODIS instrument on NASA's Terra satellite shows the clouds surrounding Hurricane Ike approximately 14 hours before landfall. [NASA Earth Observatory] Additional information and images on Hurricane Ike are on the NASA Hurricane Page. Imagery from instruments onboard the European Space Agency's Envisat satellite also helped track Hurricane Ike. [ESA]
- In eastern North Pacific, Tropical Storm Lowell over the previous weekend off the coast of southwest Mexico. During the week, Lowell traveled to the northwest through midweek before turning toward the northeast and weakening to a tropical depression. This depression made an initial landfall near the southern tip of Mexico's Baja California Peninsula late last week before traveling across the Gulf of California and making a second landfall along the western coast of mainland Mexico. Additional information concerning Tropical Storm Lowell, along with a variety of satellite imagery, can be found on the NASA Hurricane Page.
- In the western North Pacific, Tropical Storm Sinlaku formed over the waters of the Philippine Sea east of Luzon at the start of last week. During the week, it traveled to the north-northwest, intensifying to a major category 4 typhoon (on the Saffir-Simpson Intensity Scale). By late in the weekend, Sinlaku was posed to make landfall along the coast of mainland China. A satellite image was made of Typhoon Sinlaku by the MODIS instrument on NASA's Terra satellite late last week as this typhoon was brushing by Taiwan . [NASA Earth Observatory] Additional imagery and information concerning Sinlaku are available from the NASA Hurricane Page.
  A tropical storm, identified as Tropical Storm 16, formed briefly over the waters to the east of Japan.
Another Chesapeake Bay "smart buoy" deployed -- On this past weekend, NOAA deployed one of its "smart buoys" where the Susquehanna River empties into the head of Chesapeake Bay in an effort to monitor the weather, oceanographic and water quality at the northern end of the nation's largest estuary. This buoy is the fifth in the Chesapeake Bay Interpretive Buoy System that marks the Capt. John Smith Chesapeake National Historic Trail. [NOAA News]
Historic hurricane tracks website is updated -- NOAA's Coastal Services Center along with the National Hurricane Center have updated the interactive "Historical Hurricane Tracks" website that permits users to generate custom maps showing the path of tropical cyclones (hurricanes and tropical storms) in the Atlantic and eastern North Pacific basins between 1851 and 2007. [NOAA News]
Circumnavigation of the Arctic basin possible -- An image of the Arctic sea ice concentration generated from data obtained at the end of the first week of September by the Advanced Microwave Scanning Radiometer–Earth Observing System sensor on NASA’s Aqua satellite showed sufficiently open Arctic waters in the Northwest Passage through the Canadian Archipelago and the Northern Sea Route along the Russian coast for navigation around the basin's ice pack for the first time in at least 50 years. [NASA Earth Observatory]
A crack detected floating ice tongue -- An image made from data collected by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite one week ago shows a large crack that developed in the floating ice tongue attached to northwestern Greenland's Petermann Glacier. This floating ice tongue is reported to be the Northern Hemisphere's largest. [NASA Earth Observatory]
Marine vessel fuel emissions remain a global concern -- Faculty members from the Rochester Institute of Technology and the University of Delaware warn that the emissions from ocean vessels provided significant contributions of greenhouse gases and particulate matter that would seriously impact the planetary climate. They champion a strategy of improved emission control policies and a switch to cleaner fuels with lower sulfur. [Rochester Institute of Technology]
New rules governing activities in fragile polar regions to be considered -- Experts at a UN-affiliated conference marking the International Polar Year in Iceland are considering a new internationally coordinated set of rules designed to govern commercial and research activities in the Arctic and Antarctic for the protection of these fragile polar regions on both the ocean and landmasses. [EurekAlert!]
Spinning eddies in Southern Oceans could affect planetary climate -- A research team headed by a mathematician from Australia's University of New South Whales report that the large gyres, or massive spinning eddies, in the Southern Oceans could have a profound influence on marine life and ultimately upon global climate, as they appear to trap pollutants, nutrients and drifting living organisms, as well as diverting major ocean currents. [EurekAlert!]
Tropical African climate linked to Northern Hemisphere circulation patterns -- Scientists from Brown University, the University of Arizona and the Royal Netherlands Institute for Sea Research, who have examined lake bottom core sediments collected from southeast Africa's Lake Tanganyika discovered that over the last 60,000 years, the regional climate has been linked with atmospheric and oceanic circulation patterns associated with the Northern Hemisphere. [EurekAlert!]
Climate models accuracy confirmed by ice cores -- A researcher from Oregon State University claims that analysis of the concentrations of carbon dioxide and other trace gases trapped in bubbles contained in ancient ice cores obtained from Antarctica indicate that the carbon dioxide levels during a 70,000 year span with the most recent Ice Age appear to correlate well with abrupt changes in climate. The study also supports the theory that ocean currents and circulation patterns play an essential role in creating different patterns of warm and cold climates. Some suggest that this discovery confirms the validity of computer climate models that would project a warmer future climate. [EurekAlert!]
A miscalculation in undersea geologic record is uncovered -- A scientist from the University of Miami studying oceanic sedimentary records from three ocean basins for the last 10 million years claims that the assumptions made to date carbonate sediments based upon a radiochemical dating method using the ratio between the carbon-13 and carbon-12 isotopes are incorrect and would affect the dating farther into the past. [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.

THE AUTUMNAL EQUINOX -- The Autumnal Equinox will occur Monday morning (officially at 1544Z, 22 September 2008 or 11:44 AM EDT, 10:44 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 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 Sunday, 21 December 2008.
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 autumnal and spring equinoxes because of their equatorial orbit. At these times, 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

15 September 1752...A great hurricane produced a tide (storm surge )along the South Carolina coast that nearly inundated downtown Charleston. However, just before the surge reached the city, a shift in the wind caused the water level to drop five feet in ten minutes. (David Ludlum)
16 September 1928...Hurricane San Felipe, a monster hurricane, which left 600 dead in Guadeloupe and 300 dead in Puerto Rico, struck West Palm Beach, FL causing enormous damage, and then headed for Lake Okeechobee. Peak winds were near 150 mph. The high winds produced storm waves that breached the eastern dike on Lake Okeechobee, inundating flat farmland. When the storm was over, the lake covered an area the size of the state of Delaware, and beneath its waters were 1836 victims. The only survivors were those who reached large hotels for safety, and a group of fifty people who got onto a raft to take their chances out in the middle of the lake. (David Ludlum) (Intellicast)
16 September 1988...Hurricane Gilbert made landfall 120 miles south of Brownsville, TX in Mexico during the early evening. Winds gusted to 61 mph at Brownsville, and reached 82 mph at Padre Island. Six-foot tides eroded three to four feet of beach along the Lower Texas Coast, leaving the waterline seventy-five feet farther inland. Rainfall totals ranged up to 8.71 in. at Lamark, TX. Gilbert caused $3 million in property damage along the Lower Texas Coast, but less than a million dollars damage along the Middle Texas Coast. During its life span, Gilbert established an all-time record for the Western Hemisphere with a sea-level barometric pressure reading of 26.13 inches (888 millibars). Winds approached 200 mph, with higher gusts. Gilbert devastated Jamaica and Mexico's Yucatan Peninsula. (The National Weather Summary) (Storm Data) (The Weather Channel)
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)