Upwelling / Productivity
We see life everywhere on Earth. I have been lucky to see huge redwood trees, rich rain forests, and clouds of birds and insects that we regularly find on land. But amazingly, most of the life on earth is not on the land. Almost ¾ of our world’s surface is ocean. And for all its size, most of the life in the ocean is concentrated mostly near the surface and in shallow coastline waters. Much of that life is plant-life.
Undersea plants are vital to the ocean food chain and, just like on land, these plants need light in order to thrive. Since sunlight doesn’t penetrate very deep into the water, a lot of the plants are actually tiny “phytoplankton” that live very near the ocean surface where light is easy to find. You know how sometimes water looks more green versus blue? That has to do with how much phytoplankton there is reflecting sunlight off the water.
Where I live in California, we note that the ocean water is different colors at times and, of course, how it is different than the water coming from the Bay. Also, the water on the coast of Northern California is surprisingly cold, which not only effects the weather, but also the type of phytoplankton that exists there. Where does that cold water come from? There is something happening, called “Upwelling”
Upwelling is when temperature change causes sea water to turn over and the deep, cold water from the bottom comes up to replace the surface water. This is a natural process and brings new nutrients to the surface for more phytoplankton to flourish. This process takes place on a huge scale in our oceans and is not only the beginning of the food chain, but also where most of the Earth’s oxygen is created!
The ocean is the source of life on this planet, but don’t take my word for it. Follow the links on www.bigelow.org/vendeeglobe/, and http://www.oceanplanet.org/ to learn from some “real” ocean scientists!
Bruce Schwab, Skipper
USA 05/Ocean Planet