DATASTREME OCEAN WEEK SEVEN: 22-26 March 2010

Items of Interest:

• International observances --
Several days during this upcoming week have been designated as special days that are intended to focus public attention on the environment and earth science:
• "World Water Day" --
Monday, 22 March 2010, has been designated by the United Nations as the annual World Water Day, with this year's theme identified as "Clean Water for a Healthy World," which has a goal of raising the profile of water quality at the political level, to a level that would be alongside considerations of water quantity. The United Nations Educational, Scientific and Cultural Organization (UNESCO) will lead the activities of the World Water Day 2009 with the support of United Nations Economic Commission for Europe and the Food and Agriculture Organization of the United Nations. Observance of World Water Day around the world arose from the 1992 United Nations Conference on Environment and Development in Rio de Janeiro. [UN-Water]
• "World Meteorology Day" --
Tuesday, 23 March 2010 is World Meteorology Day. This day is designated to celebrate the anniversary of the establishment of the World Meteorological Organization (WMO) on 23 March 1950. The WMO is an agency within the United Nations. The theme of this year's World Meteorological Day for 2010 is "http://www.wmo.int/wmd/index_en.html" marking the 60 years of scientific and socio-economic benefits to the international community provided by WMO.
• Tsunami Awareness Week --
NOAA and the National Tsunami Hazard Mitigation Program have designated this upcoming week (21-27 March) as the first Tsunami Awareness Week. Open houses will be held at the National Weather Service's tsunami warning centers in Alaska and Hawaii, and community tsunami awareness activities will be conducted in coastal states. [NOAA News] The Governor of Alaska, along with NOAA, has proclaimed this coming week (21-27 March 2010) as Tsunami Awareness Week in Alaska. This start of this week coincides with the 46^th anniversary of the series of devastating tsunamis that struck southeastern Alaska following several earthquakes. [Governor's Office for State of Alaska]

Ocean in the News:

• Eye on the tropics --
The western South Pacific basin remained active last week, as Tropical Cyclone Ului continued to travel to the southwest, gradually weakening to tropical storm status before making landfall along the northeast coast of Queensland, Australia over this past weekend. Over the previous weekend, Ului had become a major category 5-cyclone on the Saffir Simpson Scale near the Solomon Islands. See the NASA Hurricane Page for additional information and satellite images of Tropical Cyclone Ului.
Earlier in the week, Tropical Cyclone Tomas became a major category-3 cyclone as it traveled southward across the Fiji Islands, resulting in significant damage to the islands. Tomas later intensified to a category-4 cyclone as it traveled to the south-southeast over the southwest Pacific, before weakening and finally dissipating by midweek. Satellite images and additional information concerning Tomas are on the NASA Hurricane Page.
A unique image of the two powerful tropical cyclones was obtained from the MODIS sensors onboard NASA's Aqua and Terra satellites early last week. [NASA Earth Observatory]
• Pacific smelt are listed as threatened --
Early last week, NOAA’s Fisheries Service announced that Pacific smelt (eulachon), small ocean-going fish that are found in the eastern North Pacific and Bering Sea have been listed as threatened under the Endangered Species Act. [NOAA News]
• Atlantic bluefin tuna not placed on list --
The proposal sponsored by the Principality of Monaco and supported by the US to list Atlantic bluefin tuna (Thunnus thynnus) under Appendix I of CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) was not adapted by the International Commission for the Conservation of Atlantic Tunas (ICCAT). [NOAA News]
• Steps announced that would provide equitable enforcement to protect marine resources --
NOAA administrator, Dr. Jane Lubchenco, recently outlined specific steps her agency has either taken or will take to assure that effective and fair enforcement program will protect fisheries and other marine resources. This action is in response to a January review made by the US Commerce Department Inspector General. [NOAA News]
• Clarification of federal protective actions is needed --
A report prepared by the National Research Council indicates that while the actions proposed by the US Fish and Wildlife Service and NOAA's National Marine Fisheries Service to reduce water diversions in the California Bay-Delta are "scientifically justified" as a means to protect endangered and threatened fish species, these actions need additional clarification and evaluation. [National Academies]
• New Arctic Future Website focuses on impacts of sea ice loss --
NOAA recently unveiled a website entitled "Future of Arctic Sea Ice and Global Impacts" that is designed to provide the public, businesses and government officials with easy-to-understand cause-and-effect-graphics and links to the scientific literature demonstrating how changes in the Arctic sea ice could impact the weather and climate of polar and midlatitudes. [NOAA News]
• Review of global weather and climate for February 2010 and boreal winter --
Using preliminary data collected from the global network of surface weather stations, scientists at NOAA’s National Climatic Data Center have determined that the combined global land and ocean surface temperature for February 2010 was the sixth highest for any February since global climate records began in 1880. They also noted that the combined land-ocean temperature for the three months of December 2009, January and February 2010 was also the fifth highest for this three-month Northern Hemisphere winter-Southern Hemisphere summer season. Furthermore, the average global ocean surface temperatures for both February and the three-month season were the second highest on record. Correspondingly, the global land surface temperature for February 2010 was 14th highest, while that of the December 2009-February 2010 was the 13th highest.
The areal coverage of Arctic sea ice was below the 1979-2000 average and represented the fourth lowest February extent since satellite surveillance began in 1979. Conversely, the extent of Antarctic sea ice was above average, marking the eighth largest February extent on record.
The Northern Hemisphere snow cover was the third largest on record during February, while the snow cover across North America for the three-month winter season was the largest on record that started in the late 1960s. [NOAA News]
• Is the current El Niño making a "last hurrah"?
-- An oceanographer with NASA's Jet Propulsion Laboratory who has been monitoring the current El Niño event has noted that sea-level height data obtained from the NASA/European Ocean Surface Topography Mission/Jason-2 oceanography satellite appears to indicate an eastward-moving wave of warm water, known as a Kelvin wave, may signal a "last hurrah" for this El Niño. [NASA Earth Observatory]
• Rapid response oceanographic expedition deployed to Chilean earthquake site --
A "rapid response" expedition, called the Survey of Earthquake And Rupture Offshore Chile, is being conducted by scientists from the Scripps Institution of Oceanography onboard the research vessel Melville in the coastal waters off Chile. This expedition is to explore the rupture site of last month's 8.8-magnitude Chilean earthquake, studying the changes in the seafloor due to movements along faults and by submarine landslides. [EurekAlert!]
• Shrimp found under Antarctic ice --
A researcher with NASA's Jet Propulsion Laboratory and colleagues have used a small submersible camera that he designed to investigate the waters approximately 600 feet under the West Antarctic ice sheet. They discovered Lyssianasid amphipod, a pinkish-orange shrimp creature, swimming beneath the ice. [NASA JPL]
• Winds across the Southern Ocean seen to influence rate of climate change --
Using seven years of data collected from the Argo fleet of profiling floats, Australian and US scientists have discovered that changes in the intensity of the prevailing winds blowing over the Southern Ocean have driven variations in the depth of the surface layer of sea water. This surface-mixed layer is responsible for regulating air-sea exchanges of heat and carbon dioxide, thereby influencing the rate of climate change. [CSIRO]
• New environmental satellite is renamed GOES-15 --
As is tradition, once one of the newly launched Geostationary Operational Environmental Satellite (GOES) satellites has been tested by NASA and NOAA engineers, a change in names takes place. At the end of last week, the new GOES-P satellite that was launched nearly two weeks ago was renamed GOES-15. This new satellite, which is the last of the current GOES-N-P series of environmental weather satellites, will be stored in geosynchronous orbit and will be used once one of the earlier satellites malfunctions. While the satellite was launched by NASA, NOAA will assume operational control of it. [NASA GSFC]
• 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, drought, floods, 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, to include drought, floods and storms during the current month. [NCDC]
• Earthweek --
Diary of the Planet [earthweek.com] Requires Adobe Acrobat Reader.

Concept of the Week: Seiche Model

A seiche (pronounced "say-sh") is a rhythmic oscillation of water in an enclosed basin (e.g., bathtub, lake, or reservoir) or a partially enclosed coastal inlet (e.g., bay, harbor, or estuary). With this oscillation, the water level rises at one end of a basin while simultaneously dropping at the other end. A seiche episode may last from a few minutes to a few days. (Refer to pages 156-157 in your textbook for more on seiches.)

With a typical seiche in an enclosed basin, the water level near the center does not change at all but that is where the water exhibits its greatest horizontal movement; this is the location of a node. At either end of an enclosed basin, vertical motion of the water surface is greatest (with minimal horizontal movement of water); these are locations of antinodes. The motion of the water surface during a seiche is somewhat like that of a seesaw: The balance point of the seesaw does not move up or down (analogous to a node) while people seated at either end of the seesaw move up and down (analogous to an antinode).

Go to the University of Delaware's Seiche Calculator at http://www.coastal.udel.edu/faculty/rad/seiche.html. Set the "Modal Number" to 1 and then press "Calculate" for a graphical simulation of a seiche in an enclosed basin.

Partially enclosed basins usually have a node located at the mouth (rather than near the center) and an antinode at the landward end. Go to the Seiche Calculator, set the "Modal Number" to 0.5 and then press "Calculate" for a simulation of a seiche in a basin open to the right. Furthermore, some basins are complex and have multiple nodes and antinodes; these can be simulated on the Seiche Calculator by selecting different values of "Modal Number" greater than one.

The natural period of a seiche depends on the length and depth of the basin and generally ranges from minutes to hours. The period is directly proportional to basin length. For example, the natural period of a seiche in a small pond is considerably less than its period in a large coastal inlet. Also, for the same basin, the natural period is inversely proportional to water depth; that is, the period shortens as water deepens. Using the Seiche Calculator, you may wish to experiment with different basin lengths and depths. Conversely, one can determine the average depth of a lake by determining the period of the seiche and the length of the lake.

Concept of the Week: Questions

1. In an enclosed basin the node of a seiche is located [(at either end) (near the center)] of the basin.
2. The natural period of a seiche [(depends on) (is independent of)] the size of an enclosed basin.

Historical Events:

• 22 March 1778...Captain James Cook of the British Royal Navy sighted Cape Flattery, in present day Washington State.
• 22 March 1999...Tropical Cyclone Vance produced Australia's highest measured wind speed of 166 mph at Learmonth, West Australia. Gusts reaching 185 mph were estimated in the eyewall in the Exmouth Gulf. All homes in the village of Exmouth were either damaged or destroyed. (Accord's Weather Guide Calendar)
• 24 March 1955...The first seagoing oil drill rig (for drilling in over 100 feet of water) was placed in service by the U.S. company C.G. Glasscock Drilling Co. The rig was able to drive piles with a force of 827 tons and pull a pile with the force of 942 tons. (Today in Science History)
• 24 March 1989...The tanker Exxon Valdez grounded on a reef in Prince William Sound, AK, spilling 10.1 million gallons of crude oil, resulting in the worst oil spill in U.S. history. Coast Guard units responded and prevented the entire cargo from spilling, cleaned up the oil which did spill, and conducted an investigation into the causes of the accident. The spill provided the impetus for the passage of the Oil Protection Act in 1990. (US Coast Guard Historians Office)
• 25 March 2000...A rouge wave near Shelter Cove, CA swept a lady from a Canadian school group into the ocean. Four members of the group tried to rescue her, but were overcome by the waves and currents. A fishing vessel and the US Coast Guard rescued two of the rescuers. (Accord's Weather Guide Calendar)
• 26 March 1845...Joseph Francis of New York City patented a corrugated sheet-iron lifeboat. (Today in Science History)
• 26 March 1946...The International Ice Patrol resumed after being suspended during World War II. (US Coast Guard Historians Office)
• 26-28 March 2004…The first ever confirmed hurricane in the South Atlantic Ocean, named Catarina, struck the coast of the Brazilian states of Santa Catarina and Rio Grande do Sul with heavy rains and winds, before dissipating over land late on the 28th. (The Weather Doctor)
• 27 March 1513...Spanish explorer Juan Ponce de Leon sighted Florida (and the continent of North America) for the first time, mistaking it for another island. (Wikipedia)
• 27 March 1827...At the age of 18, Charles Darwin submitted his first report of an original scientific discovery to the Plinian Society in Edinburgh, Scotland. Darwin had made several discoveries about the biology of tiny marine organisms found along the Scottish coast. (Today in Science History)
• 27 March 1899...The first international radio transmission between England and France was achieved by the Italian inventor G. Marconi.
• 27 March 1930...The first US radio broadcast was made from a ship at sea.
• 27-28 March 1964...The most powerful earthquake in US history, the Good Friday Earthquake, rocked south central Alaska, killing 125 people and causing $311 million in property damage, especially to the city of Anchorage. The earthquake in Prince William Sound, which had a magnitude of 9.2 on the Richter scale, caused some landmasses to be thrust upward locally as high as 80 feet, while elsewhere land sank as much as 8 feet. This earthquake and submarine landslides also created a tsunami that also produced extensive coastal damage. A landslide at Valdez Inlet in Alaska generated a tsunami that reached a height of 220 feet in the inlet. A major surge wave that was approximately 100 ft above low tide caused major damage to Whittier (where 13 died) and other coastal communities in Alaska. The first wave took more than 5 hours to reach the Hawaiian Islands where a 10-foot wave was detected, while a wave that was 14.8 feet above high tide level traveled along portions of the West Coast, reaching northern California 4 hours after the earthquake. Nearly 10,000 people jammed beaches at San Francisco to view the possible tsunami, but no high-amplitude waves hit those beaches. Tsunami damage reached Crescent City in northern California. Tens of thousands of aftershocks indicated that the region of faulting extended a distance of about 600 miles. The Alaska Tsunami Warning Center was established because of this disaster, with a mission to warn Alaskan communities of the threat from tsunamis. [See the 1964 Prince William Sound Tsunami page from the University of Washington.] (Accord's Weather Guide Calendar) (US Coast Guard Historians Office)
• 27 March 1980...Waves to 20 feet and winds to 58 mph in the North Sea southwest of Stavanger, Norway led to the collapse of an oil rig accommodation platform. The deaths of 123 of the 212 people on the platform were the world's worst drilling catastrophe. (Accord's Weather Guide Calendar)
• 28 March 1848...USS Supply reached the Bay of Acre, anchoring under Mount Carmel near the village of Haifa, during expedition to explore the Dead Sea and the River Jordan. (Naval Historical Center)
• 28 March 1910...Henri Fabre became the first person to fly a seaplane after taking off from a water runway at Martigues near Marseilles, France. (Wikipedia)

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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.