Upwelling

When I talked about the Gulf of Guinea, I mentioned that it was a site of coastal upwelling. There are different kinds of upwelling, depending on how the process occurs. Upwelling can occur off the coast or in the open ocean. Today, I’m going to give a general overview of upwelling.

Upwelling is a process in which deep, cold water is brought to the surface of the ocean. Upwelling occurs when wind pushes the surface water away, allowing the deeper water to rise to the surface. This cold water is typically full of nutrients that are vital for seaweed and plankton growth, creating areas of high productivity.

In this nutrient-rich water, seaweed and plankton population increases drastically, which sets off a chain reaction. The large amount of seaweed attracts herbivorous fish, and the large amount of plankton attracts filter feeders and small fish. Larger fish are attracted by all the small fish. Sharks, dolphins, and even sea birds are attracted by the large amounts of fish in the area.

Areas of upwelling are very important to both the ocean and to humans.

Upwelling provides food for all kind of fish, marine mammals, and sea birds. Think of the open ocean as a desert. It’s so vast and deep that it could be days before a dolphin or a shark can find their next meal. Areas of upwelling in the open ocean are like an oasis, especially for migratory animals who might not encounter a lot of food on their long journeys.

Coastal upwelling covers about 1% of the world’s oceans, but it provides about 50% of all our harvested fish. Some of the most successful fishing grounds occur in or around areas of upwelling. And when something happens and the upwelling stops, like in an El Niño weather event, the fishing industry takes a heavy hit, harvesting fewer and smaller fish.

Upwelling is so important that scientists and businesses are joining together to try and figure out how to create artificial upwelling using technology. So if you’re looking for a job in something groundbreaking, look into artificial upwelling! I have a feeling that it’ll be an important endeavor for years to come.

Sources and links:
https://oceanservice.noaa.gov/facts/upwelling.html ⇐ brief look into upwelling
https://www.nationalgeographic.org/encyclopedia/upwelling/ ⇐ more in-depth view of upwelling and coastal upwelling
https://oceanexplorer.noaa.gov/explorations/02quest/background/upwelling/upwelling.html

Gulf of Guinea

Let’s travel to the eastern side of the Atlantic Ocean, right off the coast of Africa. Between Cape López, near the Equator, and Cape Palmas lies a body of water known as the Gulf of Guinea.

The Volta River and the third largest river in Africa, the Niger River, are the major rivers that feed into the Gulf of Guinea. Because of the runoff from these two rivers, and the high amounts of rain along West Africa, the gulf’s water is lower in salinity than other parts of the ocean. This warm water is separated from deeper, colder, saltier water by a shallow thermocline.

A thermocline is a thin, distinct layer in a body of water that marks when the temperature of the water rapidly changes with depth. In the ocean, it separates the upper mixed layer near the surface and the deep, calm water below. Thermoclines exist in the atmosphere as well.

Off the coast of Guinea and Côte d’Ivoire, a seasonal coastal upwelling forms in the gulf. An upwelling occurs when cold, nutrient-rich water from the deep is brought up to the surface water. This nutrient-rich water creates a boom of activity that attracts organisms from every level of the food chain, including fish, birds, and mammals. When the nutrients are depleted, the organisms move on.

The Gulf of Guinea has been nominated as a Hope Spot. The beaches around the gulf contain prime nesting sites for leatherback sea turtles, which are a threatened species. Sea turtles grow for many years before they reach sexual maturity, and the process of reproduction can be fatal to females. Newly hatched sea turtles have a high mortality rate because of predation before they reach the ocean and from human activity. It’s extremely important to protect these nesting sites.

Within the Gulf of Guinea lies the island nation of São Tomé and Príncipe, which contains vital habitat for humpback whales, African manatees, dolphins, and soft corals. Humpback whales are considered endangered by the IUCN Red List their populations are threatened by whalers and by getting struck by cruise liners and cargo ships. African manatees are classified as vulnerable.

The Niger River is being explored for oil and gas mining, which could have a serious impact on the Gulf of Guinea. Luckily, non-government organizations (NGOs) have been working hard with both government and international partners to develop green practices to extract those natural resources. The NGOs have also been developing full-scale wildlife law enforcement programs to protect the gulf and its wildlife.

This is definitely a cool Hope Spot and I wish them the best of luck. If you travel to any of the beaches containing turtle nesting sites, see if there are any volunteer programs you can join. I know in the US there are volunteer programs that help get the baby sea turtles into the water. May not be the ideal vacation plan, but it’ll be something memorable to share with your friends and family!

Sources:
https://mission-blue.org/hope-spots/
https://www.britannica.com/place/Gulf-of-Guinea