|Researcher at Sea
Climate Change and our Oceans
The burning of fossil fuels, along with other human activities, is significantly increasing the amounts of
carbon dioxide (CO2)
in our atmosphere. The artificial increase of this greenhouse gas has been recognized as a major contributor to the global warming. By the end of the century global temperatures are predicted to increase by 2 to 10 degrees Fahrenheit. We are already beginning to see the effects warming can have on our environment - record high annual temperatures, melting ice sheets, and rising sea levels. Even our open oceans, once thought resilient to human impacts, are now starting to show evidence to the contrary.
The Souring of Our Oceans
The oceans play a major role in natural cycling of carbon on our planet and currently absorbs and processes half of the CO2 produced by human activities. The continual assault of CO2 is starting to take its toll on our oceans.
The pH of pristine seawater measures from 8 to 8.3 (slightly alkaline). When CO2 dissolves in seawater it forms carbonic acid. As more CO2 is taken up by the oceans surface, more carbonic acid is produced thus decreases pH (more acidic state). This phenomenon is called “ocean acidification” and is happening at a rate that hasn’t been experienced for at least 400,000 years and probably for the last 20 million years.1
and Graphics Library. 2005. UNEP/GRID-Arendal.
19 Aug 2008
Ocean Acidification - a decrease of ocean pH due to the formation
of carbonic acid as a result of increased dissolved CO2
CO2 + H2O = H2CO3 = H+ +HCO3-
Carbon dioxide + Water =
Carbonic Acid = Hydrogen + Bicarbonate
Survival in a Sour Ocean
EFFECTS OF OCEAN ACIDIFICATION
Many organisms in the oceans make their shells and other parts out of calcium carbonate – taking the ingredients they need directly from the ocean.
When ocean pH drops the chemical composition of seawater changes making some of the needed ingredients no longer available for use.
Organisms that can not make their shells die.
WHO ARE THESE ORGANISMS? WHY SHOULD WE CARE?
Many of the affected organisms are microscopically small and probably unknown to most of us but they play important role in the aquatic food web.
Others - like coral and oysters – are more recognizable and support commercial industries as well as being a vital link in the aquatic environment.
Looking for Distress Signals
On August 12, 2008, Dr. Johan Schijf will join colleagues from California and British Columbia aboard the R/V Tully as they out to explore the effects that climate change is having on the chemistry and biology of our living oceans.
Follow along on his journey across the Pacific:
Research Project Description - Johan describes the "whys" and "hows" of his research.
Research Cruise Plan - Check out where Johan trip will take him!
Cruise Logs - Follow along as Johan shares his experiences at at sea!
Ask Johan a Question - Want to know more? Just ask!
Learn more about Johan Schijf.
1 Ocean Acidification - the other half of the CO2 problem. May 2007. EUR-OCEANS Knowledge Transfer UnitEUR-OCEANS Knowledge Transfer Unit.