Ocean Currents Surface Currents Deep Currents THE RUBBER

Ocean Currents Surface Currents & Deep Currents

THE RUBBER DUCK JOURNEY: JANUARY 10, 1992: Somewhere in the middle of the Pacific Ocean nearly 29, 000 First Years bath toys, including bright yellow rubber ducks, are spilled from a cargo ship in the Pacific Ocean. 75 N 90 N 60 N 45 N 30 N 15 N 0 0 30 E 60 E 90 E 120 E 150 E 180 150 W 120 W 90 W 60 W 30 W 0

THE RUBBER DUCK JOURNEY: NOVEMBER 16, 1992: Caught in the Subpolar Gyre (counter-clockwise ocean current in the Bering Sea, between Alaska and Siberia), the ducks take 10 months to begin landing on the shores of Alaska. 75 N 90 N 60 N 45 N 30 N 15 N 0 0 30 E 60 E 90 E 120 E 150 E 180 150 W 120 W 90 W 60 W 30 W 0

THE RUBBER DUCK JOURNEY: June 16, 1995: The ducks take three years to circle around. East from the drop site to Alaska, then west and south to Japan before turning back north and east passing the original drop site and again landing along the coast of Washington state. 75 N 90 N 60 N 45 N 30 N 15 N 0 0 30 E 60 E 90 E 120 E 150 E 180 150 W 120 W 90 W 60 W 30 W 0

THE RUBBER DUCK JOURNEY: July 30, 1996: A duck washes up in the Kure Islands, in the middle of the Pacific. 75 N 90 N 60 N 45 N 30 N 15 N 0 0 30 E 60 E 90 E 120 E 150 E 180 150 W 120 W 90 W 60 W 30 W 0

THE RUBBER DUCK JOURNEY: April 9, 1997: A duck makes its way to the small Hawaiian Island of Lanai. 75 N 90 N 60 N 45 N 30 N 15 N 0 0 30 E 60 E 90 E 120 E 150 E 180 150 W 120 W 90 W 60 W 30 W 0

THE RUBBER DUCK JOURNEY: 1995 to 2003: Some ducks head North, through the Bering Straight and into the frozen waters of the Arctic. Frozen into the ice the ducks travel slowly across the pole, eastward. Ducks begin reaching the North Atlantic where they begin to thaw and move Southward. July 3, 2003: A duck finally washes up on the east coast of the U. S. on the coast of Maine. 75 N 90 N 60 N 45 N 30 N 15 N 0 0 30 E 60 E 90 E 120 E 150 E 180 150 W 120 W 90 W 60 W 30 W 0

THE RUBBER DUCK JOURNEY: July 15, 2007: The first rubber duck finally reaches England. 75 N 90 N 60 N 45 N 30 N 15 N 0 0 30 E 60 E 90 E 120 E 150 E 180 150 W 120 W 90 W 60 W 30 W 0

You. Tube Duck Song • https: //www. youtube. com/watch? v=RPUm. Rmdcjw

Surface Currents

Surface Currents

What about debris from the Japan tsunami? • Video clip of tsunami debris hitting the U. S.

Surface Currents • Horizontal, stream like movements of water that occur at the surface of the ocean. • Ex: Gulf Stream is 100 miles wide; 2, 000 feet deep with a max speed of 5 mph

3 Factors that Influence Surface Currents: • Global Winds • Coriolis Effect • Continental Deflection

Deep Ocean Currents • Caused by differences in density (temperature & salinity) • Move along ocean bottom from poles to equator. (avg speed = 8 miles a day) • Ex: Polar Creep

Deep Ocean Current

Mixing of Surface & Deep Currents • Very little mixing occurs between surface and deep currents. (thermocline temperature zone) • Upwelling: Winds move warm surface water away allowing cold deep water to move up and replace it. Brings nutrients and minerals to the surface which feed plankton.

Ocean Temperature Layers

Upwelling

El Nino Activity

El Niño of the late 1990 s It rose out of the tropical Pacific in late 1990 s. By the time it had run its course the giant El Niño of the late 1990 s had changed weather patterns around the world, killed an estimated 2, 100 people, and caused at least 33 billion [U. S. ] dollars in property damage. Along the coast of Peru (west coast of South America) weeks of heavy rain caused coastal rivers to flood their banks, five or six inches of rain a day in some places. Peru was where it all began, but El Niño’s abnormal effects on climate (including: sunshine, temperature, atmospheric pressure, wind, humidity, precipitation, cloud formation, and ocean currents) changed weather patterns across the equatorial Pacific and in turn around the globe. Indonesia and surrounding regions suffered months of drought. Temperatures reached 108°F in Mongolia; Kenya’s rainfall was 40 inches above normal; central Europe suffered record flooding; and Madagascar was battered with monsoons and cyclones. In the U. S. mudslides and flash floods flattened communities from California to Mississippi, storms pounded the Gulf Coast, and tornadoes ripped Florida. Aside from the climate related disasters the El Niño of the late 1990 s caused it also marked the first time that climate scientists were able to predict abnormal flooding and droughts months in advance, allowing time for threatened populations to prepare. Perhaps the most important effort was the development of the TAO (tropical atmosphere/ocean) array of 70 moored buoys to span the equatorial Pacific. They monitor water temperature from the surface down to 1, 600 feet [500 meters]. Thanks to the TAO buoys, and a variety of other tools, climate scientists now have information of unprecedented range and accuracy, which has enabled them to confirm and expand their theories about what occurs both during normal weather patterns and the arrivals of El Niño.

Buoy Location Across the Pacific Ocean

Normal Conditions (Equatorial Pacific) The climate in the equatorial Pacific is usually determined by sunlight heating the surface zone of the western Pacific around Australia and Indonesia, causing huge volumes of hot, moist air to rise thousands of feet creating a low-pressure system at the ocean’s surface. As the air mass rises and cools, it sheds its water content as rain, contributing to monsoons in the area. Now much drier and higher in the troposphere, the air heads east, guided by winds in the upper atmosphere, cooling even more and increasing in density as it travels. By the time it reaches the west coast of the Americas, it is cold and heavy enough that it starts to sink, creating a high-pressure system near the water’s surface. The air currents then flow as trade winds back toward Australia and Indonesia. As the trade winds blow westward over the Pacific, they push the warm top layer of the ocean with them, causing the hottest water to pile up around Indonesia. All along the coast of the Americas, and especially off Ecuador and Peru, colder deep ocean currents upwells to replace the warm water that was carried away by the global winds, bringing to the surface nutrient rich water from the deep ocean. That wealth of nutrients from the deep ocean sustains an enormous food web and makes the coastal waters off Peru one of the world’s best for fishing.

El Nino Conditions (Equatorial Pacific) El Niño changes all that. For reasons that scientists still do not understand, every few years the trade winds weaken or even disappear. Without the trade winds the warm top layer of the eastern Pacific does not move west. It stays in place, getting hotter and hotter. This causes the humid air above the extremely warm ocean to rise and condense as torrential rain on the west coast of the Americas. This, in turn, reduces the salinity of the coastal seas, where deep ocean upwellings have already stopped. Marine life that customarily thrives on upwellings off Ecuador and Peru now search for cooler, richer waters. Because El Niño moves the rains that would normally soak the western Pacific toward the Americas, such places as Australia, Indonesia, and India may experience severe drought. Meanwhile, back in North America, the jet streams that travel 5 to 8 miles above Earth’s surface shift dramatically. The polar jet stream tends to stay farther north over Canada than usual; as a result, less cold air moves into the upper United States.

El Nino Summary • Predictable, occurring every 2 -12 years • The South Pacific Trade Winds slow down or stop, moving less warm tropical water to Australia & Indonesia. • Temps rise along the west coast of South America • Stops upwellings along South America, which means no nutrients, disrupting the food chain. • Affects ALL life in ocean & on land • Change between ocean & atmosphere cause global climate change.

El Nino’s Affect on Global Climate • Dry conditions in the western Pacific (Australia & Indonesia) • Heavy rainfall in South America (Peru) & Southern U. S. • Mild winter temperatures in Northern U. S.

El Nino