BEIJING, June 21 (Xinhuanet) -- Because of Earth's warming temperatures, more and more free-floating icebergs are breaking away from Antarctica and becoming "hot spots" for marine life with complex webs of life teeming below and seabirds above, a new study reveals.

    The rising temperatures at the South Pole are causing Antarctic ice shelves to shrink and break apart into thousands of icebergs that drift out to sea.

    Researchers examined two icebergs drifting in the Weddell Sea, an arm of the Southern Atlantic Ocean that slices into Antarctica southeast of South America's Cape Horn, and discovered the icebergs transport material from the continent and release it further out at sea as they melt.

    This material produces a "halo effect" of increased biological activity for a radius of more than two miles around the icebergs.

    The team used a small remotely operated vehicle (ROV) to explore the undersides of the icebergs and underwater caves. The researchers could then identify and count the animals in the images the ROV sent back; they found significant increases in phytoplankton, krill (a staple food for whales and seals) and seabirds.

    The findings are detailed in the June 22 issue of the journal Science.

    The thriving iceberg communities may act as a new source of organic carbon, as well as a new carbon sink, as phytoplankton take up carbon dioxide from the atmosphere for photosynthesis, then die and sink to the ocean's bottom where the carbon can be stored for many years.

    "While the melting of Antarctic ice shelves is contributing to rising sea levels and other climate change dynamics in complex ways, this additional role of removing carbon from the atmosphere may have implications for global climate models that need to be further studied," said study team leader Ken Smith of the Monterey Bay Aquarium Research Institute.

    (Agencies)