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Oceans and the Climate By Chris Santomassi and Jake Coughlin

By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

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Page 1: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

Oceans and the ClimateBy Chris Santomassi and Jake Coughlin

Page 2: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

El Niño-Southern Oscillation El Niño is a period of changes in pressure

between Tahiti and Darwin and the warming of the central and East Pacific ocean

There is no clear cut cycle for when this happens but its general cycle has been noticed to occur every 3 to 8 years

What exactly causes the change in temperature are still unknown but are being researched

El Niño is believed to indirectly cause droughts and floods and drastically affect the fishing and agriculture industries

Page 3: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

La NiñaLa Niña is the name for the cold phase of ENSO

(El Niño-Southern Oscillation) when the water in the Eastern Pacific ocean cools and the trade winds get stronger. It is regarded as the opposite of El Niño and causes cooling rather than warming

During La Niña cyclone occurrences become more frequent and precipitation usually rises in the mid-west North America and in Asia

The mid-west and Canada are especially affected and during La Niña longer winters are recorded albeit, with more snow

Page 4: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

The ocean conveyor belt (Thermohaline circulation)

THC is the circulation of ocean currents on a very large scale caused by global density gradients

THC can alter climate because it circulates heat which is a form of energy and many different dissolved substances to different regions that would not normally contain them

Page 5: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

THC cont.This system of fluctuating ocean waters

is heavily affected by climate because cooler temperatures would make the water move slower and possibly cause it to become stagnant and stop circulating

A warmer climate, however would reduce how dense the water becomes and force it to circulate faster

Page 6: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

THC cont.Water gains salinity when the rate of evaporation is

high and salts become more diluted in water when there is an influx of freshwater which usually comes from melting ice or a river, lake pouring into the ocean

Water gains density when it loses heat, usually by traveling to higher altitudes and water loses density by gaining heat usually by moving to lower altitudes because more sun hits lower altitudes than higher ones due to the Earth’s axis

However, dense water masses are not always in this condition and need water masses of different densities to flow so that they can become stably stratified

Page 7: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

THC cont.Water that is less salty floats over water that

contains dissolved salts because the high salinity content has more mass because it fills “interstices” between water molecules, this floating is called stable stratification

However, dense water masses are not always in this condition and need water masses of different densities to flow so that they can become stably stratified

Page 8: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

THC cont.The thermohaline circulation is instigated in

the North Atlantic and Southern oceans where differences in temperature and salinity shift water masses.

Salinity also plays a role in thermohaline circulation because water that has a higher salinity content is more dense than fresh water

Salinity and temperature are the predominant driving force of deep water circulation

Page 9: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

THC cont.The water moves due to heat because when it’s

at the poles water is very cold and dense at which point it sinks and slowly travels to the poles

At the poles the water becomes less dense due to the heat and moves above the cold water to the poles

Thermohaline circulation moves water very slow, rarely moving faster than 10cm per second, it does transport massive amounts of water, having to move all the water in all of the oceans

Page 10: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

Coriolis effectCaused by the movement of air while the Earth

is rotating, and as a result the masses of air curve clockwise in the northern hemisphere and counterclockwise in the southern hemisphere

The circulating wind has a large effect on the surface of the oceans and can alter its course, deeper ocean currents are largely unaffected by wind and caused many early oceanographers to think that deep water remained static

Coriolis effect

Page 11: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

Coriolis effect cont.As air moves from a high pressure system to

a low pressure system in the Northern hemisphere the air masses are deflected to the right by the Coriolis effect, the Coriolis effect has the opposite effect in the Southern hemisphere where air is deflected to the left

The strength of the winds play a big role, as winds that are strong get deflected a lot while weaker winds are only slightly deflected.

Page 12: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

Coriolis effect cont.The winds correlation to the poles is also

especially relevant since winds that are closer to the poles will be deflected more than winds traveling at the same speed at the equator

The force of the Coriolis effect is zero at the equator

The Coriolis effect is linked to prevailing winds and the rotations of storms and in the hydrosphere where it affects the rotation of ocean currents

Page 13: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

Works Cited "Consequences of rotation for weather." Csep10.phys.utk.edu. Web. 19 Oct. 2009.

<http://csep10.phys.utk.edu/astr161/lect/earth/coriolis.html>. "The Coriolis Effect: A (Fairly) Simple Explanation." Polar Satellite Meteorology at

CIMSS. Web. 19 Oct. 2009. <http://stratus.ssec.wisc.edu/courses/gg101/coriolis/coriolis.html>.

"Coriolis Effect." Abyss.uoregon.edu Web Server. Web. 19 Oct. 2009. <http://abyss.uoregon.edu/~js/glossary/coriolis_effect.html>.

"Coriolis Force: an artifact of the earth's rotation." WW2010 (the weather world 2010 project):. Web. 19 Oct. 2009. <http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/fw/crls.rxml>.

"Coriolis Home Page." Physics at Oregon State University | Department of Physics. Web. 19 Oct. 2009. <http://www.physics.orst.edu/~mcintyre/coriolis/>.

"Global Warming and the Thermohaline Circulation: A negative feedback mechanism." San Jos&eacute; State University - Powering Silicon Valley. Web. 19 Oct. 2009. <http://www.sjsu.edu/faculty/watkins/thermohaline.htm>.

"Thermohaline circulation." Methane catastrophe. Web. 19 Oct. 2009. http://www.killerinourmidst.com/THC.html

. "Thermohaline Circulation: The Global Ocean Conveyor." Windows to the Universe. Web. 19 Oct. 2009. <http://www.windows.ucar.edu/tour/link=/earth/Water/circulation1.html>.

Page 14: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

Works Cited cont.http://www.seisdeagosto.com/indica/wp-conten

t/uploads/2006/05/Coriolis_effect14.pnghttp://www.windows.ucar.edu/earth/Water/ima

ges/thermohaline_circulation_conveyor_belt_big.gif

http://www.windows.ucar.edu/earth/images/currents1.jpg

http://www.windows.ucar.edu/earth/images/currents1.jpg

http://people.uncw.edu/tobiasc/GLY%20150/Abrupt%20Climate%20Change%20FAQ_files/conveyor-belt.gif

http://www.mbl.edu/news/press_releases/images/thermohaline_circulation.jpg

http://oceanography.earthednet.org/Mini_Studies/Deep_Ocean_Circulation/Deep_Ocean_Circulation_files/image009.jpg

http://www.liv.ac.uk/physocean/schematics/thc.gif

http://www.geology.um.maine.edu/ges121/lectures/19-ocean-conveyor/conveyor.jpg

Page 15: By Chris Santomassi and Jake Coughlin. El Niño-Southern Oscillation El Niño is a period of changes in pressure between Tahiti and Darwin and the warming

Recommended sitesWindows.ucar.eduEncyclopedia BritannicaAtmos.uiuc.edu