Earth to warm even if greenhouse gas cut - US study
Date: 20-Sep-02
Country: USA
If nations cut back on emissions, it will not heat up as
much, but it will still be hotter than it is now, according
to a computer climate model.
"Some continued global warming will occur ... even if the
greenhouse gases in the air do not increase further, but the
warming could be much less than the worst-case scenarios,"
lead researcher James Hansen said in a statement.
If emissions continue to increase at the current rate,
global temperatures may increase by 2-4 degrees Fahrenheit
(1-2 Celsius) the study found.
But if carbon dioxide emissions do not increase any faster
than they are now and if nations cut emissions of true air
pollutants - those harmful to humans - temperatures might
only rise 1.4 degrees Fahrenheit (.75 Celsius).
The climate model provided a convincing demonstration that
global temperature change of the past half-century was
mainly a response to climate forcing agents, or imposed
perturbations of the Earth's energy balance, researchers
found.
This was especially true of human-made forcings, such as
carbon dioxide and methane, which trap the Earth's heat
radiation as a blanket traps body heat.
Hansen is based at NASA's Goddard Institute for Space
Studies in New York City, but the research was a
collaborative effort among 19 institutions, including seven
universities, federal agencies, private industry and other
NASA centers, and was funded by NASA.
The results appear in the current Journal of Geophysical
Research-Atmospheres.