Irminger Current Correlation to Wind Speed Wind speeds across the Irminger Sea can reach up to 47 m/s, signaling the location of the Irminger current.

White arrows show the Irminger Current. This current is fed by the Gulf Stream carrying warm surface water along the North Atlantic. It then turns into the North Atlantic Current as it proceeds north - the offshoot of the North Atlantic current becomes the Irminger current. This current is still a warm surface current with high salinities.

The white arrows represent the East Greenland Current. This current is fed by the Beaufort Gyre north of Alaska – a slow, clockwise moving water mass. It is a cold, low density, high velocity current. The low density of this current is attributed to the melting of Arctic sea ice in the summer.

Formation of Deep Water This picture shows the formation of deep water at 2 specific sites in the North Atlantic marked by crosses. Deep water circulation currents are the bolded arrows, while surface currents are the dotted arrows. One site, off the southwestern coast of Greenland marks the formation of intermediate water (LSW – Labrador Sea Water). The other, north of Iceland, is the formation of deep water (DSOW – Denmark Strait Overflow Water).

· The Antarctic Peninsula is the northern most tip of the continent so it has a warmer and wetter climate than the coastal areas.

· The peninsula has some of the continent’s strongest winds and fiercest storms.

· The peninsula sometimes experiences sustained westerlies and gales days or even weeks on end.

· The peninsula has a greater a amount of life than other regions of the continent. Many birds and marine mammals nest and breed on the shores of the peninsula.

1819- William Smith from Blyth, on a voyage from Buenos Aires to Valparaiso, was driven toward the South. (Smith was the first to chart the Antarctic Peninsula at 64°S.)

1820- “Captain Nat” (Nathaniel B. Palmer) and his men became the first Americans to discover the Antarctic Peninsula.

1821- John Davis, an American seal hunter, set foot on the continent. He and his crew landed near the top of the Antarctic Peninsula.

Palmer Station, is located on Anvers Island. It is the only US station north of the Antarctic Circle. The station is named for Nathaniel B. Palmer.

- Alyssa, Tiffany, & Shannon

For most of our known history, the Arctic has posed as a mysterious frontier too harsh for most to survive. There are stories of attempts at exploration of the region dating all the way back to 325 BC by Pytheas of Massilia who claimed to have seen a land where the sun set for merely 3 hrs at a time and described what is believed to be sea ice. There were many attempts at exploring the Arctic Ocean, but not until 1896 was it first successfully navigated as Fridjtof Nansen made the first nautical crossing, while in 1968-69 Wally Herbert made the first successful crossing by dog sled as he parted from Alaska and reached the Norwegian island of Svalbard.

As the Arctic Ocean is the converging point of the world ocean, there are a number of crisscrossing currents that meet there. Both warm and cold water are lead there by the boundary currents along the American and Eurasian continents. The warm water (depicted by the red arrow on the map) is largely produced by the North Atlantic Intrusion water, which is produced at the tail of the Gulf Stream. This water enters the Arctic between Iceland and Europe and then follows its path circling the polar ocean. The cold water (depicted by the blue) which then interferes with it originates from a number of Siberian seas along the northern coast of Russia along with from the Pacific via the Bering Strait.

A few years back now Russia sent two mini subs down to plant their flag below the North Pole claiming a territory close to five times the size of England. This area is suspected to contain gratuitous amounts of oil; possibly up to twice the amount found in Saudi Arabia. The availability of this new resource could be very valuable to the country, boosting the Russian economic status. However most countries are in debate with Russia on this bold move saying that Russia doesn’t have the right to claim the area as their own. With the ever-diminishing ice cap, more and more of the sea floor below is becoming available for study and most feel it should be open for everyone, not sectioned off for a countries personal use.

Aicha, Joe and Nilsen

A gyre is large system of rotating ocean currents, particularly those involved with large wind movements. Gyres are caused by the Coriolis Effect.

Ocean Gyres

The South Atlantic Gryre is located in the Southern Hemisphere in between the East coast of South America (Brazil) and the West coast of Africa. Since the South Atlantic Gyre is in the Southern Hemisphere it circulates in a counter-clockwise direction because the Coriolis affect is reversed.

Atlantic Ocean Gyres

The Brazil current is the South Atlantic Gyre’s western boundary current and brings warm equatorial water to the pole. The Benguela current is the eastern boundary current, bringing cold Antarctic water towards the equator. The South Atlantic’s northern boundary is the South Equatorial Current and it is bordered on the south by the Antarctic Circumpolar Current. The South Atlantic Gyre is one of 5 major gyres, the others being the North Atlantic Gyre, The Indian Ocean Gyre, the North Pacific Gyre, and the South Pacific Gyre.

Ocean Gyres and Circulation

-Amelia, Kyle, Emily

The Antarctic Circumpolar Current (ACC), also known as the West Wind Draft, is a massive west-to-east flowing current in the Southern Ocean encircling Antarctica. Though its flow rate can be relatively slow in areas, the ACC is said to be one of, if not the largest the largest ocean current at 125 Sverdrups (Sverdrups (Sv) are oceanographic units of volumetric measurement: one Sv is equal to 10⁶ cm³/s, or approximately264 gallons per second). The ACC extends from the sea surface to depth s of 2000-4000 m and can be as wide as 2000 km; hence the large volume transport. The primary driver of this massive eastward current is a strong westerly wind; hence the alternative name of the West Wind Draft. The ACC connects four oceans: the Pacific, Atlantic, Indian, and Southern Oceans.

The ACC generally maintains temperature between -1°C and 5°C. Due to the rotary nature of the ACC, it has kept warmer, saltier waters from the tropical regions away from Antarctica. It flows through Drake Passage and is then split by Scotia Arc with a shallow warm water current flowing north to Falkland Current, and then passes through Indian Ocean until it is split by Kerguelen Plateau.

Antarctic Surface Water (ASW) originates near the Antarctic continent. It flows to the north until it encounters Subantarctic Surface Water. Because it is denser than the Subantarctic Surface Water, ASW begins to sink and mix with underlying Subantarctic Intermediate Water. The region of convergence between these surface water masses is referred to as the Antarctic Convergence or Polar Front. North of the Polar Front, surface waters have winter temperatures warmer than approximately 2.0°C (35.6°F), and they are relatively salty. South of this front, surface waters have winter temperatures below 1.0°C (33.8°F) and are less salty.

The core of the ACC is derived from Circumpolar Deep Water, which is a mixture of deep water from all of the affected oceans. The shallower portion of the current contains oxygen-poor water sourced from all contributing oceans, while the deeper portion contains high-salinity water primarily from the Atlantic. The coldest, saltiest water in the ocean is produced on the continental shelf around Antarctica in winter. The sources: the Weddell and Ross Seas. During sea ice formation, the cold and highly saline water (formed as a byproduct of sea ice formation) drains from the shelves deeper to the seafloor, giving it access to seep into all surrounding ocean basins.

The ACC and climate change are directly related. Being that it connects 4 of the world’s oceans, heat is constantly being redistributed. This directly influences global and regional atmospheric and oceanic temperature, precipitation, etc. Density-driven vertical movement of water circulates water between the surface and benthic areas. At the surface, there is exchange of gases (part of the global carbon flux) at surface; therefore, the rate of absorption of gases (primarily Carbon Dioxide) directly affects the Earth’s climate. Stronger westerly winds (due to increased human activity and ozone depletion) are carrying more heat, which is delivered directly into the ACC. These winds increase eddy activity that play a role in distributing heat southwards, towards the pole). This is leading to rapid warming of Antarctica and the Antarctic Peninsula (a particular region [a part of Drake’s Passage] of interest due to extraordinarily rapid climate change). The area of highest study is in Drake Passage, between the southern tip of South America and the Antarctic Peninsula.

-Dave, Jessica & Karan

OK, well, we are not really looking for Drake, but our team is the 26.5 N Team so we will be researching the waters of this line of latitude. Our first step was to see where 26.5 N is:

A view across 26.5N

Florida, Bahamas, and the Continental Shelf

Mid Atlantic Ridge

African Coast

This line of latitude is important for several reasons:

1.) The Gulf Stream moves northward over by the Floridian Coast (red line):

• The Gulf Stream is important because it is a major factor in heat transfer from the South to the North. Without the Gulf Stream the weather in the Northern Hemisphere would be drastically different!

2.) The North Atlantic Deep Water runs South toward the equator (blue line):

• The NADW is important because the cold salty water from the North travels south and changes temperature and salinity of waters it encounters

3.) This line of latitude has significance in climate change:

• Ocean circulation and weather/climate are directly correlated and with all of these different currents running past 26.5N it is a great line of latitude to focus our research on.
• The transfer of warm water from the Gulf to the North and the movement of the cold and salty North Atlantic Deep Water from the North to the South are important areas to study.
• Any climate change will be seen in the change in chemistry and physics of the water and currents in this area.

Example of significance in research:

• If the Gulf Stream moves more warm water than usual to the North then the ice in the North may start to melt and dump large amounts of fresh water into the ocean disrupting the NADW circulation.

4.) There are also a series of moorings along 26.5N that are recording the current’s velocities, salinity, and temperature. Drake is also somewhere around 26.5N, or at least before the malfunction we were trying to fly along these moorings at 26.5N!

Chris Filosa, Frank Acevedo, Katie Carson

Team Equator

The equator is an imaginary line approximately 40,075,017 meters long on the Earth’s surface that is equidistant from the north and south poles, dividing the planet into the northern and southern hemispheres. It is important area to study because the surface of the Earth at the equator is mostly ocean; it crosses the Atlantic, Pacific, and Indian Oceans.

In 1735, the French Academy of Sciences sent an expedition to the equator to see if the circumference of the Earth was greater around the Equator or around the poles. Sir Isaac Newton had calculated that the equatorial exceeds the polar diameter by about 34 miles, while the French astronomer Jacques Cassini thought that the polar circumference was greater. The expedition found that the Earth is wider at the equator.

Equatorial upwelling is an important occurrence in the ocean. In the Pacific, Easterly Trade Winds push the surface water westward along the equator. The Earth’s rotation deflects the westward current toward the right in the Northern Hemisphere and toward the left in the Southern Hemisphere.

The surface waters diverge, causing cold, nutrient rich water to be upwelled from below. Phytoplankton growth is very high under these conditions, making this an area of high primary productivity.

The winds also cause warm surface water to accumulate on the western side of the Pacific. Warmer water has a lower density, and the sea level is about two feet higher on the western side of the Pacific basin than on the eastern side. This warm water contributes to the West Pacific Warm Pool, which is responsible for the monsoons in Asia that allow farmers to grow crops.

Jason and Richa

The Amazon River:

The Amazon is home to one of the largest tidal bores on earth called the Pororoca. This translates to “great destructive noise” in the indigenous Tupi language. A tidal bore is phenomena in which the leading edge of an incoming tide forms a wave against the current. This phenomena only happens a few times a year. It is up to 4 meters high and travels at up to 30 Km/hr. This event is a hot spot for extreme surfers around the world. The world record holder rode the wave for 6.3 miles which took 33 minutes.

The Amazon River is rarely visited by outsiders because it is so difficult to get to. There is not one single bridge spanning the Amazon. The indigenous say there is no need for it. There are few roads and no cities so a bridge is unpractical. The only way to get there is by a boat. The indigenous use a canoe called a curiara, which is dug out from a log. They use this as their only means of transportation.

One of the Amazon’s tributaries, the Rio Negro, causes a phenomena knows as “black water”. The Amazon is usually fed by rivers with an origin in the mountains. This causes it to be very silty. On the contrary, the Rio Negro is NOT a mountain river. Its water is very dark due to all the tropical leaves that fall into it and can be though of as a tea. When the tea water of the Rio Negro meets the silty water of the Amazon, it does not mix well.

The Orinoco River:

On August 1st, 1498 during his third voyage to the North East coast of South America, Christopher Columbus discover the mouth of the Orinoco. 453 years later, in 1951 a collaborative effort of a French and Venezuelan team fully explored the Orinoco.

Alexander von Humboldt explored the basin in the 1800’s and reported seeing pink river dolphins. It is the largest of all river dolphins. Since then, gray river dolphins have also been discovered in the amazon. They are approximately 10 feet long, and weigh about 200 pounds. There is a myth behind the pink dolphin that at night it turns into a hansom man and seduces women. The locals do not kill or eat these dolphins because they think it is bad luck. They also think the dolphins were once human.

In the native language of Guarauno, Orinoco means “a place to paddle’. The Warao tribe is the second largest tribe in Venezuela. Numbering at only 20,000 people, their entire life style revolves around the river. Like on the Amazon, their only means of transportation is the curiara. These natives are very skilled hunters, fishermen, and craftsmen.

Until next time,

Abe, Jay, and Mario