A growing number of business leaders, government officials and private citizens are concerned about global warming and its implications, and are proposing steps to reverse the trend.
Many scientists say that reversal is not possible and that certain types of destruction, such as the melting of the polar ice caps, have already gone past the point of no return. Others say that the planet Earth has the ability to heal itself. This takes time, though.
"While some argue that 'the Earth will heal itself,' the natural processes for removing this human-caused CO2 from the atmosphere work on the timescale of hundreds of thousands to millions of years," Werne said. "So, yes, the Earth will heal itself, but not in time for our cultural institutions to be preserved as they are. Therefore, in our own self-interests, we must act in one way or another to deal with the changes in climate we are causing."
There are many steps humans can take to lessen the effects of global warming. NASA is committed to a two-pronged approach:
• Reducing emissions of greenhouse gases and stabilizing the levels of these gases in the atmosphere
• Adapting to the climate change already happening
Decreasing the rate at which fossil fuels are burned is critical to that effort. Development of clean energy, including solar, wind and geothermal energy, has immense potential to reduce the amount of coal and oil burned in powering electrical generating plants, NASA said.
More-sustainable transportation options, such as mass transit and alt-fuel vehicles, will also reduce the amount of greenhouse gases in the atmosphere. (The Union of Concerned Scientists estimates that about 25 percent of energy-related CO2 emissions in the United States come from passenger vehicles.)
Even individual efforts, such as lowering thermostats in winter and using energy-efficient light bulbs, can help to address global warming. But most climate researchers also stress the immediate need for large-scale, international policies to address the complex causes and effects of global warming.