2From the Sun to Our Earth! Global movement of matter is driven by the properties of water and energyHeat Transfer:RadiationConductionConvectionConvection is the primary mechanism of energy transfer in the atmosphere, oceans and asthenosphere
3What Causes Climate and Seasons The shape of the planet and the tiltMilankovitch Cycles: Like a top the Earth wobbles and the length of the elliptical orbit changes every 100,000 years as well as the tilt, causing different latitudes to receive more or less sunlight
4What are the Major Global Convection Cells? Hadley Cells: Start at equator and rise to about N/S latitude (trade winds)Rainforests form where air risesDeserts form where air descends
5Convection CellsFerrel Cells: Exist from degrees latitude N/S (Westerlies)Polar Cells: Cold, very dry dense air (Polar Easterlies)Jet Streams: Extremely fast moving winds found at boundaries of convection cells
7How do our oceans affect weather? Trade winds created by the Coriolis Effect apply friction to the surface of the ocean and drag water in the same direction.Thermohaline currents: Temperature and salinity affect density of the ocean consequently causing currents (cold salty water is denser)Twice a day the gravitational pull from the moon causes high tides
8What is El Nino-Southern Oscillation (ENSO) ? Rise in temperature of 0.5 Celsius degrees more than normal in the Eastern Pacific Ocean near the equator, usually beginning around December (hence the name, “Christ Child”)Occurs at irregular intervals of 2-7 years and has usually lasted one or two years, but has been coming more frequently.Disrupts global weather patternsTriggered by Southern Oscillation
9What are the Effects of El Nino The deeper, warmer water in the east limits the amount of nutrient-rich deep water normally surfaced by the upwelling processSince fish can no longer access this rich food source, many of them die off
10What happens in the atmosphere? Tropical thunderstorms are fueled by hot, humid air over the oceansThe hotter the air, the stronger and bigger the thunderstormsThe east coast of southern Africa and Australia often experiences drought during El NinoDescribe economic consequences!