Oceanographer warns students about carbon-dioxide dangers

NOAA expert reports on computer modeling projects at Plainsboro facility

By: Emily Craighead
   The day after tomorrow will not bring catastrophic climate change, oceanographer Anand Gnanadesikan assured Grovers Mill Middle School eighth-graders during a presentation Tuesday.
   What the next 100 years will hold, however, no one knows for sure, he cautioned.
   "If all the ice melted, water levels would rise 40 meters — this part of New Jersey would be gone," Mr. Gnanadesikan said. "It wouldn’t flood everywhere, and it’s very, very unlikely to happen in our lifetime."
   Mr. Gnanadesikan is an oceanographer at the Plainsboro-based National Oceanic and Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory, which studies the predictability, stability and sensitivity of global and regional climate structure, and the interaction of the atmosphere and oceans. Using sophisticated computer models, scientists at the lab try to predict how climate change will affect the planet.
   Speaking to Andrew Maskell and Rae Kluge’s eighth-grade science classes, Mr. Gnanadesikan approached the question of global warming from a chemist’s point of view.
   "If not for carbon dioxide, we wouldn’t have an inhabitable planet," Mr. Gnanadesikan said. Venus, in addition to being closer to the sun, is too hot because it has too much carbon dioxide. Mars doesn’t have enough and is too cold. Earth is just about right, he said.
   Since the industrial revolution, however, carbon dioxide levels on earth have been rising.
   Carbon dioxide, he explained to the students, who are concluding a chapter on chemistry, is the Mickey Mouse molecule, because it consists of one carbon and two oxygen atoms.
   "As you add carbon to the atmosphere, the ocean chemistry changes," Mr. Gnanadesikan said.
   As more and more carbon dioxide is absorbed into the water, the chalky shells protecting organisms, such as oysters or clams, begin to flake.
   "We don’t know if the organisms will be able to adjust, or if they will just get wiped out," Mr. Gnanadesikan said. Perhaps they will evolve to create stronger cells, less dependent on the current chemical balance of the ocean.
   Proposed solutions sound like they were picked up at the corner drug store.
   The "Tums" solution calls for restoring the ocean’s chemical balance by adding calcium carbonate, or chalk. The "Geritol" solution requires adding iron to the ocean.
   Neither solution is inexpensive or practical, Mr. Gnanadesikan said. And no one can predict the side effects.
   The biggest question — how much should be spent to avoid global warming — is not one scientists can, or should, answer, he told the students. Should billions of dollars be spent to save coral reefs, or to give everyone on earth clean water?
   It is up to public policy experts, with input from scientists, to set those priorities, Mr. Gnanadesikan said.