VOCALS is a field campaign to better understand the interactions of the ocean, clouds, air, and land in the Southeastern Pacific.
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Image Courtesy of Robert Wood

Introduction to VOCALS Science

How big of a 'laboratory' would you need to conduct experiments on a climate system? Well, that probably depends on which part of Earth's climate system you want to study. In the case of the VOCALS, the VOCALS research team will conduct a series of scientific experiments using the Southeastern Pacific Ocean and the west coasts of Peru and Chile as their 'laboratory.' This region of the world will make a very large laboratory! The VOCALS experiments and observations are planned for the month of October, 2008. The team intends to increase their understanding of the interactions between the South American continent and the Southeast Pacific (SEP) Ocean.

This area of the world is very important to regional and global climates, but the interactions between the ocean, atmosphere, and land in the SEP are not well understood. VOCALS science will produce a better understanding of the SEP climate system and this information will be used to improve global climate models. Better global climate models will lead to more confidence in climate forecasts including predictions about global warming.

The SEP region is characterized by its persistent stratocumulous clouds, fog and drizzle, strong low level winds, ocean currents, nutrient rich marine habitats, cool surface sea temperature, arid desert, and the Andes Mountain range . The processes that link these components of the region are not well understood, making it difficult to represent this area accurately in global climate models. To conduct scientific research on such a large scale, specially equipped airplanes, research ships, buoys, and meteorological towers are being used to make observations and collect data.

Scientists in the VOCALS field campaign are very interested in collecting data that is needed to address a set of questions that fall into two general categories. First, scientists want to explore the interactions between aerosols, clouds and drizzle in the part of the atmosphere near the sea surface known as the marine boundary layer (MBL). These things play an important role in Earth's radiation budget by reflecting sunlight out to space. The second key area of scientific interest is learning about chemical and physical processes that occur between the upper ocean, the atmosphere, and the land. This includes the sampling of mesoscale ocean eddies by the reserach ships.

Learning more about how human activity impacts the SEP climate system will be an important part of VOCALS. For example, how do the aerosols from copper smelters affect cloud formation? If ocean temperatures warm, will there be significant changes in the economically important commercial fishing industry? How will changing climates impact human activity and the economics of this region?

VOCALS is scheduled to take place in the month of October because this is the time of year when the coverage of stratocumulus over the SEP is at its greatest, the southeast trade winds are at their strongest, and the coupling between the upper ocean and the lower atmosphere is most closely linked.

For updates from the scientists during the VOCALS campaign, check out the Postcards from the Field. VOCALS Scientists will be posting updates during the month of October 2008.

Last modified October 13, 2008 by Julia Genyuk.

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