For Immediate Release Contact: Nancy Light, IODP-MI, 202-466-2457,
North Pole Was Once a Subtropical Climate Zone, Say Scientists Returning from Arctic Coring Expedition
Sept. 7, 2004?Scientists on the Arctic Coring Expedition (ACEX) have discovered that the Arctic Ocean was once ice-free, due to the effects of prehistoric global warming. The expedition team, which has been out to sea since August 7, is operating under the auspices of the Integrated Ocean Drilling Program (IODP).
"The early history of the Arctic Basin will be re-evaluated based on the scientific results collected on this expedition," said Professor Jan Backman, of Stockholm University, and ACEX co-chief scientist. "We were surprised to find freshwater conditions and periods of extreme warmth?an indication that environmental conditions were more variable than anticipated."
Expedition scientists, representing eight nations, recovered sediment cores from nearly 400 meters below the seafloor, in waters 1,300 meters deep. The retrieved cores show evidence of subtropical, shallow seas in the form of tiny fossils, actually extinct marine plant and animals. An ACEX logbook with reports and pictures can be viewed at http://www.iodp.de/.
ACEX scientists say the fossils originated in a period known as the Paleocene-Eocenethermal maximum, a brief period that occurred around 55 million years ago, characterized by an extremely warm climate generated by a natural greenhouse effect that perhaps was the result of massive carbon input to sea and air. Specific algae, identified in the core fossils, reveal that Arctic Ocean waters were once much warmer?around 68?F, similar to waters around New York in August, and vastly warmer than today?s freezing Arctic temperatures that average 29.3?F.
?We?re seeing a mass extinction of sea-bottom-living organisms caused by these changing conditions,? observed paleontologist Michael Kaminski, University College London, UK, on board the icebreaker Oden. ?Moving forward in time, we see many species disappear. Only a few hardy survivors endure the thermal maximum.?
The ACEX scientific team returns to Troms?rway, on September 14th. The scientists will meet again in November at the University of Bremen, Germany, to examine the data collected. Further study will help explain the changes in the Arctic?s climate, from greenhouse conditions to today?s icy environment.
The Integrated Ocean Drilling Program (IODP) is the most expansive marine geoscience research program operating in the world today. It investigates planet Earth, its history and structure by collecting and studying sediments and rocks beneath the seafloor. Through technologically advanced ocean-drilling techniques and multiple drilling platforms, IODP pursues scientific discovery of the deep biosphere, the sub-seafloor, environmental change processes and effects, solid earth cycles, and geodynamics. The program, managed by Integrated Ocean Drilling Management International (located in Washington, DC, and Sapporo, Japan), is funded by the National Science Foundation and Japan?s Ministry of Education, Culture, Sports, Science and Technology. For more information, visit http://www.iodp.org/.
ACEX offshore operations are managed by the European Consortium for Ocean Research Drilling (ECORD), a group that works in concert with IODP-MI on mission-specific drilling operations. Its affiliated institutions include British Geological Survey, University of Bremen (Germany), European Petrophysics Consortium (Universities of Leicester, Montpellier, Aachen and Amsterdam) and the Swedish Polar Research Secretariat.
