Shop Windows to the Universe

Dig into Montana Before History: 11K Years of Hunter-Gatherers in the Rockies and Plains by D. H. MacDonald, Ph.D. See our online store book collection.
The climate system of the Southeast Pacific region
Click on image for full size
Robert Wood (University of Washington) and the VOCALS Scientific Working Group

Southeast Pacific Climate

The Southeast Pacific Ocean region off the coastal areas of Peru and Chile is one part of the world where stratus and stratocumulus clouds are frequently present. Other areas include the subtropical climate regimes off the coast of California (US), and Namibia (Africa ). These areas are of great importance not only to regional climates, but to the Earth's global climate as well. The climates of these regions involve feedbacks between the ocean, clouds, atmosphere, and land. Scientists in the VOCALS Field campaign are focusing their experiments in the Southeast Pacific (SEP) Ocean off the coasts of Chile and Peru. They have chosen this area because the feedbacks in the regional climate systems are very clear.

The climate of the Southeast Pacific region is the result of interactions between the Andes Mountains, the ocean, and the atmosphere, including clouds. Clouds form right above the ocean, in an area known as the marine boundary layer. These clouds are of the low stratus type. They create an almost continuous blanket over much of the Southeast Pacific. The precipitation in this region is mostly in the form of drizzle.

Westerly winds blow thousands of miles across the Pacific Ocean toward South America. When they reach land and run into the Andes Mountains, they are forced to turn north. The wind causes the water at the ocean surface to move perpendicular to it, away from the coast, becasue of a process called Ekman transport. When the surface water moves westward, it is replaced by very cold, nutrient rich water from deep in the ocean in a process called upwelling. In the Southeast Pacific Ocean, upwelling is associated with the Humboldt Current system.

It appears that the atmosphere over most of the SEP is very clean. However, copper smelters located in Chile and Peru produce aerosols. Aerosols are also present naturally in this area from sea salt and plankton. Aerosols are known to affect the formation of clouds and precipitation.

Last modified September 22, 2008 by Sandra Henderson.

Shop Windows to the Universe Science Store!

Our online store includes books on science education, classroom activities in The Earth Scientist, mineral and fossil specimens, and educational games!

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Stratus

Stratus clouds belong to the Low Cloud (surface-2000m up) group. They are uniform gray in color and can cover most or all of the sky. Stratus clouds can look like a fog that doesn't reach the ground....more

Stratocumulus

Stratocumulus clouds belong to the Low Cloud (surface-2000m) group. These clouds are low, lumpy, and gray. These clouds can look like cells under a microscope - sometimes they line up in rows and other...more

What is VOCALS?

What if you wanted to learn more about the climate of a very large area of the world? What would be involved in studying how the oceans, land, and atmosphere interact? You would need to have a team of...more

Drizzle

Drizzle is light precipitation that is made up of liquid water drops that are smaller than rain drops. Drizzle can be so light that only a millimeter of water falls to the Earth's surface in one day. It...more

Winds in the Southeast Pacific

The winds in the Southeast Pacific mainly blow from south to north. They have a strong effect on the climate in the region and worldwide. The winds in this area get their start with a major flow in the...more

Ocean Upwelling

There are places in the ocean where water from the deep sea travels up to the surface. These are called areas of upwelling. The deep waters can have a large influence upon life in the ocean and the climate...more

Aerosols: Tiny Particulates in the Air

When you look up at the sky, you are looking at more than just air. There are also billions of tiny bits of solid and liquid floating in the atmosphere. Those tiny floating particles are called aerosols...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA