9 September 2011: U.S., Canada Explore Oceans’ Changing Chemistry
![A scientist prepares to deploy an Argo float off the side of the RV Wecoma, a research vessel owned by the U.S. National Science Foundation. A scientist prepares to deploy an Argo float off the side of the RV Wecoma, a research vessel owned by the U.S. National Science Foundation.](https://webarchive.library.unt.edu/web/20130218181008im_/http://photos.state.gov/libraries/amgov/3234/2011_Week_1/09082011_Argo-floats-300.jpg)
A scientist prepares to deploy an Argo float off the side of the RV Wecoma, a research vessel owned by the U.S. National Science Foundation.
U.S. and Canadian scientists are working together to understand the oceans' changing chemistry through floats that monitor the acidity and total carbon dioxide content of seawater, according to the U.S. National Oceanic and Atmospheric Administration.
The Argo floats, which measure 1.5 meters tall, drift with deep ocean currents and transmit the gathered data via satellite back to scientists, NOAA said in an August 2 press release.
"Most observations have been taken by scientists aboard specialized research ships, so this represents a major step forward in the ability to monitor ocean chemistry at higher frequency and lower cost," said Lauren Juranek, an oceanographer with the University of Washington's Joint Institute for the Study of the Atmosphere and Ocean (JISAO).
Juranek was the lead author in a study of the new method, which was published in the journal Geophysical Research Letters August 2.
According to NOAA, this new method shows how readings of ocean acidity and carbon dioxide levels can help scientists understand changes in the chemistry of the world's oceans.
The method was developed by researchers from NOAA's Pacific Marine Environmental Laboratory in Seattle, JISAO and colleagues from the Canadian Department of Fisheries and Oceans in British Columbia and Quebec.
The scientists established the method by determining the relationships among seawater temperature, oxygen, acidity and carbon dioxide through observations on ship-based expeditions during the last five years. These relationships were then applied to high-resolution observations collected by an Argo float deployed in the North Pacific in early 2010.
The Argo floats used in the study are part of the international Argo observing network, which combines about 3,000 active floats deployed throughout the world's oceans by researchers in more than 30 countries. The floats regularly collect temperature, salinity and other data that are used to determine how the oceans' chemistry is changing over time.
"These measurements can be used to complement traditional ship-based observations, not replace them. Because we can't sample as frequently as we would like to, this approach allows us to provide repeat data on 10-day intervals," said Richard Feely, a NOAA senior scientist and co-author of the study. He said that even though some ship-based work remains essential, the Argo floats give scientists a "new perspective on ocean physics and chemistry" and a more complete view of the ocean carbon system.
He said absorption of carbon dioxide causes the level of acidity in seawater to rise in a process called acidification, which can have adverse effects on organisms such as corals, mussels and oysters.
The floats are critical to understanding and predicting these changes in both the atmosphere and the ocean, and the information they provide helps to guide international actions, optimize governmental policies and shape industrial strategies, according to the International Argo Project website.
NOAA said the scientists involved in the study will continue working across national borders to learn about the Earth's environment and better conserve and manage coastal and marine resources.
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