Reported June 2009

WHAT IS GLOBAL WARMING DOING TO THE OCEANS? Global warming is raising the oceans' temperatures, but it's also making it easier to absorb Carbon Dioxide (CO2). Large amounts of CO2 -- up to a million tons an hour worldwide -- are absorbed by the ocean. This changes the chemistry of the ocean, making it slightly more acidic. This can harm the environment, including marine animals and plants, which can result in devastation of ecosystems like coral reefs. However, because more acidic seawater absorbs less low- and mid-frequency sound (the frequencies at which many animals communicate), water becomes better able to transmit certain frequencies, meaning equally loud noises can be heard farther away in water with lower pH levels.

ABOUT GLOBAL WARMING: Global warming refers to an average increase in the earth's temperature -- which has risen about 1 degree Fahrenheit over the past 100 years -- as well as to changes in climate. A warmer Earth may lead to changes in rainfall patterns, and a rise in sea level, for example, as the polar glaciers melt. Some of this rise is due to the greenhouse effect: certain gases in the atmosphere trap energy from the sun so that heat can't escape back into space. Without the greenhouse effect, the earth would be too cold for humans to survive, but if it becomes too strong, the earth could become much warmer, causing problems for humans, plants and animals.

The American Geophysical Union and the Acoustical Society of America contributed to the information contained in the TV portion of this report. This report has also been produced thanks to a generous grant from the Camille and Henry Dreyfus Foundation, Inc.

If you would like more information, please contact:

Peter Weiss
American Geophysical Union
Washington, DC 20009-1277
(800) 966-2481
http://www.agu.org
pweiss@agu.org

Acoustical Society of America
Melville, NY 11747-4502
(516) 576-2360
http://asa.aip.org
asa@aip.org

Monterey Bay Aquarium Research Institute (MBARI)
Lisa Borok
Communications Associate
Moss Landing, CA 95039-9644
(831) 775-1807
lisab@mbari.org

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