Laura Henry What is the Global Conveyor Belt? Thermohaline Temperature Salinity Deep-ocean current Downwelling Occurs at poles Upwelling Occurs at equator Continuous cycle Climate and the Global Conveyor Belt Ocean water transfers sun’s energy Regulates/normaliz es Earth’s temperature Begins in North Atlantic Moves heat towards poles Takes 1,000 years to complete Early Connections to Climate Change Wallace Broecker, 1984 Carbon levels in polar ice measured Revealed patter of high carbon levels just before ice age Rise in atmospheric temperature connected to glacial periods Later Research Studies of forams from glacial periods Forams found at intermediate ocean levels rather than in the deep sea Forams lack O^16 molecules Evidence that global warming is directly followed by ice age Global Warming’s affect on the belt Melting of ice caps diluting salt water Water in the poles becoming less dense Disrupting the process of downwelling Global warming in the past Henrich Events Sheets of ice break off glaciers Melt into Atlantic Release ice-rafted debris Dansgaard-Oescher Events (DC) Freshwater introduced into North Atlantic Antarctic deep water released CO2 transferred to atmosphere Implications of a conveyor belt shut-down Tropic zones would experience severe heat waves Moderate zones thrust into ice-age Inhabitable areas cut down Possibly no way to reverse a shut-down Too soon to know for sure Not enough research to be certain RAPID tests inconclusive Nothing of this scale has occurred before More scientific evidence in favor of a conveyor belt shut down than against it Sources http://oceanservice.noaa.gov/education/kits/currents/06conve yor.html http://science.howstuffworks.com/environmental/earth/ocean ography/ocean-current3.htm http://northwestpassage.bangor.ac.uk/diary.php http://academic.emporia.edu/aberjame/student/tinsley1/webp age1.html http://montessorimuddle.org/tag/paleontology/ http://www.rsmas.miami.edu/groups/coral-lab/faq/ http://scijinks.nasa.gov/atmosphere-formation http://www.webquest.hawaii.edu/kahihi/sciencedictionary/C/cl imatezone.php http://www.divediscover.whoi.edu/polar/impact.html http://www.esr.org/outreach/polar/what/what.html