The Arctic Ocean! •Located in the Northern Hemisphere, extends from the Bering Sea to the Northern Atlantic Ocean •Occupies a space of approximately 14,056,000 km2 (5,427,000 sq mi), about the size of Russia! It is one of the most extreme ocean environments due to the year-round ice cover and seasonal conditions Holds a great number of highly adapted organisms, many of which have not been identified The effects of Global Warming are most prominent in the Arctic Ocean due to increasing temperatures, resulting in reduction of Sea Ice The general increase in Earth’s near surface air and ocean temperatures Caused by: 1.) Natural phenomena Volcanic activity Solar variation 2.)External forcings created by human activities Greenhouse gases Aerosols(CFC’s) and soot Greenhouse gas emissions are composed of 4 major gases Carbon Dioxide (CO2): 36-70% Water Vapor: 9-26% Methane(CH4 ):4-9% Ozone(O3 ): 3-7% Ice Core samples have shown that CO2 and CH4 level are the highest they’ve ever been 650,000 years Since 1750, CO2 levels has increased by 36% and CH4 levels by 148% Increasing global temperatures leads to the reduction of Sea Ice, which in turn causes the melting of permafrost Less sea ice Less ice-albedo The melting of permafrost releases trapped methane gas, which will accelerate the global warming process (positive feedback) http://www.youtube.com/watch?v=si9n7S9663Y 7:07-9:46 Broken down into 3 realms: 1.) Sea Ice 2.)Water Column 3.) Sea Floor The Arctic sea ice covers approximately 7x106 km2 in the summer and twice that in the winter. It reaches a thickness of 2–3m and covers nearly all of the central deep basins. < http://www.arcodiv.org/SeaIce_overview.html > This year round ice hosts a variety of ice- endemic organisms, typically unicellular plants and animals. Many taxa of Sea Ice organisms still have not yet been classified Onisimus nanseni Arthropod (shrimp-like crustacean) Lifespan of 2.5 years Endemic to Arctic Boreogadus saida Arctic Cod The main source of food for many marine mammals, birds, and fishes Sympagohydra tuuli 1.1 mm long Newly discovered genus of a Hydriod (2008) Broken down into 3 realms: 1.) Sea Ice 2.)Water Column 3.) Sea Floor Inflow from surrounding oceans allows the importing of different organisms Most exotic organisms die because of the frigid environment Majority of species consists of Copepods (plankton) Highest concentrations of water column communities found in lower latitudes Gaetanus brevispinus Copepod 5mm length, 3 year lifespan Found from 1500m and up Crossota Millisae Cnidarian Some Cnidaria can survive up to 10 years, and be as large as 30m long! Broken down into 3 realms: 1.) Sea Ice 2.)Water Column 3.) Sea Floor Organisms found on sea floor rely on food found in the water column above At present, roughly 5000 species of marine invertebrates are known to inhabit the Arctic. Over 90% of those live at the seafloor 1 Roughly 350 species live in the central Arctic Sea Floor, the rest are located at lower latitudes on the continental shelf Consists mostly of crustaceans, polychaetes (bristle worms), and mollusks 1<http://www.arcodiv.org/SeaBottom_overview.html > Ctenodiscus Crispatus Echinoderm Over 50 different types of sea star species found in the Arctic Ocean Chiton (Tonisella Lineata) Mollusk Prey of humans, seabirds, seastars, crab, lobster, and fish Ursus maritimus (Polar Bear) • Associated with sea ice • Approx. size of 8.5 feet tall, 900lbs (male) • Lifespan of 25-30 years Erignathus barbatus(Bearded Seal) • Approx. size of 7 feet long, 500lbs(male) • Circumpolar arctic distribution • Lifespan of about 30 years Delphinapterus leucas(Beluga whale) • Approx. size of 12 feet long, 3500lbs (male) • Arctic and subarctic distribution, often in or near sea ice or glacial ice • Lifespan of 35-50+ years Recent investigations have estimated a loss in summer arctic sea ice of 9.2% per decade Ice endemic species* Ice algae growth is increased when sea ice melts, and interrupts the plankton blooms Higher trophic levels (marine mammals) suffer due to the lack of energy within the ocean system Animals, such as polar bears, have to change their feeding and migratory patterns due to the lack of ice http://www.youtube.com/watch?v=JMQ21p93JZc&feature=related Melting of sea ice leads to decreased ocean salinity Responsible for changing global water cycles It has been proposed by arctic geoengineers, that by actively pumping fresh water onto the pre-existing sea ice, it would freeze and thicken Thicker sea ice is less resistant to melt, and could possibly slow down the global warming process PICTURES http://pufone.org/blog/wp- content/uploads/arctic_sea_ice_2005_vs_2007_2560x1920.gif http://www.glf.dfo-mpo.gc.ca/os/bysea- enmer/images/img_mod1_p36-e.jpg INFO http://www.nwf.org/Global-Warming/Effects-on-Wildlife-and- Habitat.aspx http://www.nrdc.org/globalwarming/qthinice.asp http://www.worldviewofglobalwarming.org/pages/glaciers.html http://geography.about.com/od/globalproblemsandissues/a/globalwa rming.htm http://www.arcodiv.org/ http://www.guardian.co.uk/environment/2009/feb/15/climate- change-polar-species QUESTIONS???
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