Thinning Arctic Ice Allows Plankton Bloom

NASA scientists exploring the Chukchi Sea in the Arctic were surprised to discover massive phytoplankton blooms under the sea ice.  In the past, the ice was too thick for sunlight to penetrate and spur phytoplankton growth; however, global warming has drastically thinned the ice in many areas.  The ice where the phytoplankton bloom was discovered is 3-foot-thick first year ice that will melt in the spring.  A decade ago, this ice was 10 feet thick and did not ever melt.  This discovery, besides providing more evidence of global warming, astonished the scientists who had thought that this region did not sustain much life.  The thinner ice that allows 50% of sunlight to pass through and the nutrient-rich waters provide all the necessities for phytoplankton to thrive.  This particular phytoplankton bloom was 70 miles wide and over a hundred feet deep.  These phytoplankton blooms create new questions about the balance of the Arctic food web.  Animals that feed on plankton used to have to wait for spring to come before the plankton blooms reached their peak.  However, now that blooms are occurring under the ice, the scientists worry that it will throw off the migratory patterns of plankton-eating animals such as Arctic terns and California gray whales.  However, many birds are unable to reach their food, fish that eat under-ice plankton.  Sea animals, however, will be able to feast on this plankton with less competition than in the past.  The scientists are unsure how these plankton blooms will alter the Arctic food webs in the future, and look forward to investigating more.

            I can see how the phytoplankton blooms could upset the delicate Arctic food web.  Since there is no way to know just yet what the effect will even be, scientists cannot begin to look for solutions.  This is a scary idea because the Arctic is so rapidly changing that solutions are needed as soon as a problem arises.  By the time the effect of these plankton blooms becomes evident, it may be too late to fix the problem!  There is just no way to know; however, I will say that the animals that are predicted to benefit the most from these phytoplankton blooms (gray whales, walruses, and Eider ducks) are not endangered or even threatened species.  This could create overpopulation of these species in the future, which will obviously create problems.  Then again, with global warming threatening these species, perhaps the added food source will stabilize the population and prevent future endangerment of these species.  Only time will tell the effects of phytoplankton blooms.

Scientific American link:
http://www.scientificamerican.com/article.cfm?id=thinning-arctic-ice-allows-plankton-bloom