Introduction to Ocean Circulation - Geography 163ApproachPowerPoint PresentationSlide 4Slide 5Why do we care?Slide 7Global Heat TransportSlide 9Slide 10El NiñoSlide 12El NiñoSST Departures (oC) in the Tropical Pacific During the Last 4 WeeksNiño Region SST Departures (oC) Recent EvolutionRecent Evolution of Equatorial Pacific SST Departures (oC)NPP & ClimateSlide 18BiogeographyBiogeographical BoundariesSlide 21CO2 SequestrationSlide 23Climate & FishSlide 25ScalesGlobal BathymetryHyposgraphic CurveWind-Driven GyresGlobal Ocean CirculationSlide 31Global Wind ClimateConveyor BeltNet Air-Sea Heat FluxAtlantic TemperatureAtlantic SalinityAtlantic OxygenAtlantic PhosphateCoastal UpwellingSlide 40Slide 41SummaryIntroduction to Ocean Circulation - Geography 163 •Wind-driven circulation of major gyres & surface currents•Buoyancy-driven circulation linking the major gyres & the global conveyor belt•Coastal circulations & land-ocean interactions•Build from physical principles (w/out math)Approach•First principles do “work” •Build descriptions from first principles•Do not bludgeon students with calculus•Work with available data setsWhy do we care?•Climate–Global heat & water cycles–Weather & weather/climate prediction •Global biogeography & biogeochemistry–Species ranges & adaptation to global change–Fossil fuel CO2 sequestration•Marine resources–Renewable (fisheries)–Non-renewable (oil, etc.)IPCC [2007]Global ClimateChangeGlobal Heat TransportHow can it be constant?Global Heat TransportGlobal Heat Transport1015 W = 1 PetawattEl NiñoEl NiñoEl NiñoSST Departures (oC) in the Tropical Pacific During the Last 4 WeeksDuring the last 4-weeks, equatorial SSTs were more than 1.0°C above average between 165°E and 120°W and near the western S. American coast.Niño Region SST Departures (oC) Recent EvolutionThe latest weekly SST departures are:Niño 4 1.0ºC Niño 3.4 1.1ºCNiño 3 0.7ºCNiño 1+2 0.1ºCRecent Evolution of Equatorial Pacific SST Departures (oC)LongitudeTimeSince the beginning of June 2009, SST anomalies have been at least +0.5°C across most of the equatorial Pacific. During December 2009, positive SST anomalies increased across much of the equatorial Pacific. From late December 2009 to mid-February 2010, positive SST anomalies decreased across portions of the central and east-central Pacific. Recently, positive SST anomalies have decreased over the central Pacific.NPP & ClimateNPP = Net Primary Production rate of C fixed by phytoplanktonChlorophyll is found in all plants & phytoplanktonAverages are from persistently warm ocean (SST> 15C)From Behrenfeld et al. [2006]NPP & ClimateBiogeographyBiogeographical BoundariesBiogeographyCO2 SequestrationIt’s gotta go somewhere...CO2 SequestrationThis is where.Climate & FishPacific Decadal Oscillation Warm phase - southern Cool phase - northernWe’re now in a cool phase…Introduction to Ocean Circulation - Geography 163 •Wind-driven circulation of major gyres & surface currents•Buoyancy-driven circulation linking the major gyres & the global conveyor belt•Coastal circulations & land-ocean interactionsScales•Ocean basins are wide & shallow –Typical scales are 104 km across and 5 km deep–“Spit on a basketball”•Aspect ratio has important implications–Horizontal velocities are >> vertical velocities–Horizontal property changes are << vertical onesGlobal BathymetryHyposgraphic CurveWind-Driven GyresGlobal Ocean CirculationGlobal Wind ClimateConveyor BeltNet Air-Sea Heat FluxAtlantic TemperatureeWOCE gallery – www.ewoce.orgAtlantic SalinityAtlantic OxygenAtlantic PhosphateCoastal UpwellingCoastal UpwellingCoastal UpwellingJuly 1992AVHRR Ch 4Summary•Importance of large-scale ocean circulation–climate, biogeochemistry, marine resources•Characteristic “Types” of Ocean Circulation –Patterns of circulation can be generalized for different regions–Suggests that dynamical processes are the same –Wind-driven, Buoyancy-driven & Coastal•Scales - “spit on a