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This material is available primarily for archival purposes. Telephone numbers or other contact information may be out of date; please see current contact information at media contacts.
Arctic Ocean Provides Clues to Global Climate and Environmental ChangesScientists from seven different countries will spend their summer vacation on the icy Arctic Ocean, investigating the causes of global climate and environmental changes. Supported by the National Science Foundation (NSF)'s Ocean Drilling Program (ODP), a research expedition to this high northern latitude ocean will take place from July 7 to September 3, 1995. Sailing aboard the largest scientific drill ship, the JOIDES Resolution, the scientists will study Arctic Ocean effects on the transfer of heat to the atmosphere, and deep water formation and ventilation there, which control or influence both oceanic and atmospheric carbon chemistry. "These water masses are sometimes referred to as the 'lungs' of the present world oceans because they contribute significantly to the ventilation of global ocean water," explains Peter Blum, a staff scientist with ODP. "Continuous sections of sediment cores from the deep ocean floor will allow us to reconstruct physical and chemical changes in these deep water masses over time, at scales of tens to millions of years, through analysis of the records preserved in the cores." Seafloor sediments, containing minerals and skeletons of Arctic marine organisms, are a natural archive that records the environmental conditions of the Arctic Ocean and surrounding continents. In times past, Arctic waters were warmer and free of ice. The dramatic changes in climate that brought frigid conditions to both poles left a signature deep in the ocean floor that can be retrieved only by scientific drilling. This summer's expedition follows the first exploration of the Arctic Ocean floor during the summer of 1993, when ODP scientists drilled the world's northernmost borehole, located about 570 kilometers from the North Pole. The international team of more than 50 scientists and technicians will drill holes and collect core samples to better understand deep and shallow water exchange between the Arctic Ocean and the Norwegian-Greenland Sea. These core samples will also provide information on water mass evolution, particularly initiation and variability of oceanic fronts in surface waters, as well as northern deep water formation. "We will supplement the north-south and east-west drill site transects of 1993 with about 15 additional holes at eight sites," says Blum. "This will provide sediment cores from the range of latitudes and water depths needed to reconstruct the history of these globally important water masses." Other objectives for the research cruise include investigating polar cooling and the evolution of low- to highlatitude thermal gradients in the northern hemisphere; sea-ice distribution; and the glacial history of the Arctic, as well as Greenland and Northern Europe. The Arctic acquired its ice cover between five and 15 million years ago. During the past few million years, some 26 glaciation events have affected northern polar seas and lands. Today, this frozen region remains one of the least accessible, and therefore explored, on Earth.
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