HAMPTON, Va. - Global warming predictions need some adjusting if new NASA research holds true.
Scientists Bruce Wielicki and David Young are working with the Clouds and the Earth's Radiant Energy System project.
The program uses a satellite to sweep across Earth and look at regions about the size of Hampton. The instrument studies how much energy Earth gets from the sun, how much is reflected, and how much energy the planet releases into space on its own.
That data will help scientists better understand Earth's climate and develop better computer models to predict how the globe will warm in years to come.
The predictions give policy-makers reasons to implement regulations to ward off global warming, but the project's research has shown that current computer models still need tweaking.
For example, during El NiM-qo in 1997, researchers saw large losses of heat in the tropics. But computer models had predicted no significant heat loss.
That kind of misinformation could prompt unnecessary rules or no rules where some are needed, Young said.
"The government doesn't want to impose regulations on the populace if there isn't going to be that big of a change in climate," Young said.
The problem with current models comes when looking out over the next 100 years or so. While predictions are fairly accurate if skies are clear, adding clouds can produce problems.
That's because clouds can either absorb or reflect light. Many scientists think Earth's temperature is rising, but how clouds would affect that is still up in the air.
More clouds could reflect sunlight and cause a cooling effect or trap heat in the atmosphere and make things hotter.
"That's the big complication," Young said of clouds.
And it comes when the need to understand an apparent warming trend is growing.
Earth's surface is expected to warm more in the next century than any other in the past 10,000 years, according to the U.S. Global Change Research Information Office.
Temperatures at Earth's surface rose by about 1 degree Fahrenheit during the 20th century, according to the U.S. agency. The average temperature on Earth is about 60 degrees Fahrenheit. During the last ice age, it was about 52 degrees Fahrenheit.
Computer models predict that average global surface temperature will rise between 2.5 and 10.4 degrees Fahrenheit by the end of this century, and part of that discrepancy comes because of the cloud influence, the NASA researchers said.
"On any given day, 2 degrees isn't a big deal," Young said. "Averaged over a year and over the globe, it's huge."
Already researchers are seeing melting glaciers, thinning Arctic ice and rising sea levels, as well as longer growing seasons in many areas and earlier arrival of migratory birds.
Problems of warming
According to a report by the Intergovernmental Panel on Climate Change, problems are likely to rise with the temperatures, with Third World countries bearing the brunt of the misfortune.
Third World countries have less money to spend on flood management and drought concerns, according to the intergovernmental agency.
But even in developed nations, such as the United States, increased temperatures could become a problem.
The heat would mean changes in farmlands as tropical zones and arid zones expand from the equator.
The increase in tropical regions would also mean an increase in tropical diseases, according to the panel.
Plus, global sea level is expected to rise 6 to 37 inches by 2100, increasing the threat of coastal flooding.
Whether the warming trend is due to human activity or is a natural cycle remains debatable, but the U.S. Global Change Research Information Office and intergovernmental agency both agree that strong evidence points to increased burning of fossil fuels and deforestation.
It was just that kind of global warming concern that spurred the cloud work.
The scientists began looking into the weather wildcard using a satellite launched in 1997 aboard the Tropical Rainfall Measuring Mission.
In 1999, the Clouds and the Earth's Radiant Energy System project, or CERES, expanded what scientists could study by using five instruments to track everything from water vapor to what dust particles are in the air.
CERES has just compiled its first year of data from the 1999 launch. The data show that clouds decrease the worldwide average temperature by 20 degrees Fahrenheit.
Even more work is planned, as researchers hope to launch another satellite aboard the Aqua mission slated to launch next year. That mission will basically give similar data but at later times of day than what CERES currently records.
Eventually, researchers hope to have a myriad of data at once, from temperatures throughout the atmosphere to the amount of moisture.
Wielicki said the missions need several decades worth of data before becoming a more reliable tool.
"This is really a whole new way of looking at the world," he said.