IODP Tahiti sea level expedition gets underway

October 07, 2005

Off the coast of Tahiti, IODP scientists will take samples of fossil corals from the ocean seafloor to analyze the environmental records that are inside them. Scientists expect the coral reefs to yield records on changes in sea surface temperature during the circumscribed period and information on climatic anomalies, including El Niño/Southern Oscillation events.

Through this research expedition, IODP scientists aim to learn more about the timing and course of past global sea level changes to better understand present and future sea level rise due to global greenhouse conditions. Since the climax of the last ice age, global sea level has risen by about 120 meters, primarily because of the melting of large inland ice sheets and thermal expansion of the global body of ocean water?attributable to rising temperatures.

According to IODP scientists, Tahiti is well situated for these investigations because the island is located in a tectonically stable region. Consequently, changes in sea level here can be related solely to global effects. Because the corals off Tahiti have strict ecological requirements and are extremely sensitive to environmental changes, both natural and human-induced, they are accurate, sensitive recorders of past sea level and climatic change.

The science party will analyze fossil, i.e. dead corals, because they form archives that help decipher the long-term behavior of the tropical ocean-atmosphere system and how it has responded to manmade and natural impacts. Live corals will not be cored, nor analyzed.

Because corals live in a sufficiently narrow depth range, they can be used as absolute sea level indicators. Corals can be considered chronometers as they can absolutely date by radiometric methods, methods so accurate that even in the oldest coral rocks to be studied, scientists will be able to accurately determine the age of corals to within 50 years.

Expedition co-chief scientist Yasufumi Iryu of Japan's Tohoku University says, "We are very excited about being able to understand these past environmental changes in such detail for the first time."

French co-chief scientist Gilbert Camoin of the CEREGE Institute adds, "Understanding the rate at which sea level and environments have changed is vital to understanding the effects that human activity now have on Earth's environment."

At the conclusion of the expedition, the fossil coral core material will be shipped to an IODP core repository located at the University of Bremen, Germany. In mid-February 2006, IODP scientists will gather again in Bremen to further analyze the fossil corals and associated reef rocks in greater detail.
-end-
More about the science party's activities will be posted during the course of the expedition at www.ecord.org (general information) or www.iodp.de (expedition logbook).

ESO, the ECORD (European Consortium for Ocean Research Drilling) Science Operator, is managing the Tahiti Sea Level Expedition on behalf of IODP. Coordinated by the British Geological Survey, ESO includes the University of Bremen and the European Petrophysics Consortium (Universities of Leicester, Montpellier, Aachen and Amsterdam). In addition to ECORD funding, ESO is supported by IODP, in part, with commingled funds from the U.S. National Science Foundation and Japan's Ministry of Education, Culture, Science, and Technology. See www.ecord.org for more information.

The Integrated Ocean Drilling Program (IODP) is an international marine research program dedicated to advancing scientific understanding of the Earth by monitoring and sampling subseafloor environments. Through multiple platforms, IODP scientists explore the program's principal themes: the deep biosphere, climate change, and Earth processes. Mission-specific drilling platforms are operated by the ECORD Science Operator (ESO), one of three IODP Implementing Organizations. Two others?in Japan and in the United States?conduct riser-equipped and riserless drilling operations, respectively. IODP's initial 10-year, $1.5 billion program is supported by two lead agencies, the U.S. National Science Foundation and Japan's Ministry of Education, Culture, Sports, Science, and Technology. ECORD and the People's Republic of China Ministry of Science and Technology give additional support. More program information about IODP is available at www.iodp.org.

For more information, interviews, images, contact an IODP program office:

France
Christiane Grappin
christiane.grappin@cnrs-dir.fr
Tel.: +33 (0) 1 44 96 43 37

UK
Andy Kingdon
aki@bgs.ac.uk
Tel.: +44 (0)115 936 3415 (office)
+44 (0)7779 616 602 (mobile)

Germany and Central Europe
Albert Gerdes
agerdes@marum.de
Tel.: +49 421 218-655 40 (office)
+49 172 43 77 986 (mobile)

North America
Nancy Light
nlight@iodp.org
Tel.: +1 (202) 465-7511
+1 (202) 361-3325 (mobile)

Integrated Ocean Drilling Program Management International

Related Sea Level Articles from Brightsurf:

Sea-level rise will have complex consequences
Rising sea levels will affect coasts and human societies in complex and unpredictable ways, according to a new study that examined 12,000 years in which a large island became a cluster of smaller ones.

From sea to shining sea: new survey reveals state-level opinions on climate change
A new report analyzing state-level opinions on climate change finds the majority of Americans believe in and want action on climate change--but factors like state politics and local climate play important roles.

UM researcher proposes sea-level rise global observing system
University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science researcher Shane Elipot proposes a new approach to monitoring global sea-level rise.

How much will polar ice sheets add to sea level rise?
Over 99% of terrestrial ice is bound up in the ice sheets covering Antarctic and Greenland.

Larger variability in sea level expected as Earth warms
A team of researchers from the University of Hawai'i (UH) at Mānoa School of Ocean and Earth Science and Technology (SOEST) identified a global tendency for future sea levels to become more variable as oceans warm this century due to increasing greenhouse gas emissions.

Sea-level rise could make rivers more likely to jump course
A new study shows that sea level rise will cause rivers to change course more frequently.

UCF study: Sea level rise impacts to Canaveral sea turtle nests will be substantial
The study examined loggerhead and green sea turtle nests to predict beach habitat loss at four national seashores by the year 2100.

Wetlands will keep up with sea level rise to offset climate change
Sediment accrual rates in coastal wetlands will outpace sea level rise, enabling wetlands to increase their capacity to sequester carbon, a study from the Marine Biological Laboratory, Woods Hole, shows.

How sea level rise affects birds in coastal forests
Saltwater intrusion changes coastal vegetation that provides bird habitat. Researchers found that the transition from forests to marshes along the North Carolina coast due to climate change could benefit some bird species of concern for conservation.

As sea level rises, wetlands crank up their carbon storage
Some wetlands perform better under pressure. A new Nature study revealed that when faced with sea-level rise, coastal wetlands respond by burying even more carbon in their soils.

Read More: Sea Level News and Sea Level Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.