Leslie Field, an engineer and Portola Valley resident, has a plan for covering polar ice to slow its melting and will give a presentation at 7:30 p.m. Tuesday, Dec. 7, in the Community Hall at 765 Portola Road.
As North Pole ice melts, the Arctic Ocean becomes less white, which means less sunlight — and less heat — reflected through the atmosphere and out into space. The increasingly darker ocean then absorbs increasingly more heat.
"It's a positive feedback loop, which will always get an engineer's attention," Ms. Field said in a phone interview. "What can one do to interrupt that (feedback loop)?"
What she has done is experiment with tiny spheres of reflective glass. There are details to be worked out, but if such microspheres of glass were implanted in fabric-like squares about three-feet on a side, with the fabric distributed on the surface of the ice, it might work, Ms. Field said.
About 20 percent of global warming is due to melting ice, she said. As the oceans warm, significant change could come to major currents such as the Gulf Stream, which has moderated weather on both sides of the Atlantic Ocean since the last ice age.
Notions are out there to "fertilize" the ocean with iron filings to encourage greenhouse gas absorption by plankton, or to add particles to the upper atmosphere to reflect sunshine. Such fixes are commonly known as geo-engineering, but Ms. Field prefers to call her idea eco-engineering.
Scientists worry about unintentional consequences. The airborne particles, for example, could reduce the efficiency of solar driven power plants by 20 percent, according to a 2009 study by the National Oceanic and Atmospheric Administration.
Ms. Field's proposal benefits by being relatively inexpensive, relatively benign, and reversible, she said, adding that she has done small-scale tests in the Sierra Nevadas and on a Canadian lake, and that she is hoping to find funding for a larger test.
Go to www.ice911.org for more information.