Washington, Sept 16: A new study conducted at the National Center for Atmospheric Research (NCAR) suggests that a two-pronged approach, involving both injecting sulfate particles in the stratosphere and cutting the emission of greenhouse gasses, may be more effective in cooling Earth’s temperature.
The study stresses that the impact of the two processes, which scientists refer to as geoengineering, will be much stronger if they are carried out together rather than separately.
Tom Wigley, an official at NCAR, used a computer model for the study, and calculated the impact of injecting sulfate particles in every one to four years into the stratosphere.
He tracked sunlight and other energy flowing into and out of the Earth system, and examined two scenarios that project the impact of emissions on climate from now to the year 2400.
He says that such injections can provide the world more time to cut the emission of green house gasses in the environment, provided this approach is found to be environmentally and technologically viable.
"A combined approach to climate stabilisation has a number of advantages over either employed separately," he says.
Wigley claims that it is really very difficult to cut the emission of Carbon di-oxide (CO2) to such an extent that it contains the temperature from rising more than 3.6 degrees Fahrenheit (2.0 degrees Celsius) over present levels, and this is the reason researchers began to find an alternative approach to reduce the impact of climate change.
He says that in the 1970s a strategy was proposed to cool the climate, which called for injecting large amounts of sun-blocking sulfate particles into the stratosphere via aircraft or other means.
He believes that Geoengineering can help fight the challenges economic and technological challenges faced in cutting the emission of green house gasses. "Geoengineering could provide additional time to address the economic and technological challenges faced by a mitigation-only approach," he says.
Wigley however says that geoengineering is not a panacea, as carbon dioxide from fossil fuel burning has led to an increased acidification of Earth's oceans.
He says that geoengineering may be help limit global warming, but the oceans will continue to acidify as greenhouse-gas emissions climb, threatening certain marine ecosystems.
Wigley further says that mitigation approach alone can potentially solve both the warming and ocean acidification problems, but it is facing economical and technological difficulties.
"A relatively modest geoengineering investment could reduce the economic and technological burden on mitigation by deferring the need for immediate or near-future cuts in carbon dioxide emissions," he says.
Bureau Report
First Published: Saturday, September 16, 2006, 00:00