Diane Evans NASA 248.
(photo credit: Dani Machlis/Ben-Gurion University)
Photos from space have already helped reduce the
differences between climate change models and will play a significant
role ahead of the next assessment, Dr. Diane Evans, director for earth
science and technology at NASA's Jet Propulsion Laboratory, said
Evans lectured at Ben-Gurion University of the Negev in the morning and spoke to The Jerusalem Post
by phone after her presentation.
A periodic assessment of climate change put out by the
Intergovernmental Panel on Climate Change used satellites to chart the
rise of the seas and the reduction of the ice sheets at the poles,
Evans told the Post
"The IPCC came out with their 4th assessment in 2007. The third
assessment didn't know if the ice sheets were gaining or losing mass.
We now know that they have been losing mass," she said, to demonstrate
the beneficial use of satellites in tracking environmental phenomena.
"The next assessment is supposed to come out in
2013. Between now and then, satellite imaging will be used to assess
the truth of the models. The models will be checked against the direct
observations of the satellites," she said.
Evans was here as part of an annual BGU event to remember Israeli astronaut Col. Ilan Ramon and the crew of the Columbia
shuttle, which disintegrated upon reentry into the atmosphere on
February 1, 2003. She gave a lecture in Beersheba entitled "Eyes on the
Earth: The Critical Role of Satellites in Understanding our
"What we try to do is calm the debate by providing direct observations," she remarked to the Post
According to Evans, the images have shown that the ice sheets at
the poles are melting abnormally fast, the seas are rising and the
glaciers in Antarctica and Greenland are receding even faster than the
For Evans, the debate over whether the changes are man-made or
natural is "a little beside the point, because they are definitely
happening and faster than was predicted."
Evans suggested that even if global warming was another phase
in the earth's development, moving to a carbon-free sustainable economy
was still an economically worthwhile goal, "since oil will eventually
NASA has been observing the Earth for the last 20 years and has
been looking into environmental applications "more and more." In
addition to climate change, NASA satellites have been monitoring
natural disasters. Some of the systems can even be used to trace
tension and buildup in the tectonic plates which cause earthquakes.
"The satellites can give an indication of potential magnitude,
not timing. They also show the resulting changes in stress and tensions
along fault lines in the area after an earthquake," she said.
Evans did not know whether any satellite could have offered
advance warning of the earthquake that wracked Haiti on January 12.
However, she said the research, though still in its infancy, might
eventually be useful in predicting aftershocks.