Huge Antarctic iceberg makes a big splash on sea life
"NASA satellites observed the calving, or breaking off, of one of the largest icebergs ever recorded, named "C-19".
C-19 separated from the western face of the Ross Ice Shelf in Antarctica in May 2002, splashed into the Ross Sea, and virtually eliminated a valuable food source for marine life. The event was unusual, because it was the second-largest iceberg to calve in the region in 26 months.
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Since it was so large, C-19 blocked sea ice from moving out of the southwestern Ross Sea region. The blockage resulted in unusually high sea-ice cover during the spring and summer. Consequently, light was blocked. Phytoplankton blooms that occur on the ocean surface were dramaticaly diminished, and primary productin was reduced by over 90 percent, relative to normal years.
Primary production is the formation of new plant matter by microscopic plants through photosynthesis. Phytoplankton is at the base of the food chain. If they are not able to accomplish photosynthesis, all organisms above them in the food chain will be affected. 'Calving events over the last two decades indicate reduced primary productivity may be a typical conseauence of large icebergs that drift through the southwestern Ross Sea during spring and summer, (ed. - Stanford University scientists Kevin) Arrigo said."
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http://www.eurekalert.org/pub_releases/2003-10/nsfc-hai093003.php