Thursday, November 29, 2007
Researchers studied sunsets to look for effects caused by volcanic eruptions
Greek scientist Christos Zerefos shows one of the paintings that he studied at the National Observatory of Penteli, near Athens. Zerefos led a group of Greek scientists studying the colors of sunsets in more than 500 paintings by old masters from the 16th to 19th centuries.
Scientists use paintings to track climate change
The vivid sunsets painted by J.M.W. Turner are revered for their use of color and light and for their influence on the Impressionists. But could they also help global warming experts track climate change?
A group of scientists has studied the colors in more than 500 paintings of sunsets, including many of Turner’s 19th-century watercolors and oils, in hopes of gaining insights into the cooling effects caused by major volcanic eruptions.
By better understanding past changes in climate, they hope to improve computer models for future climate change.
Christos Zerefos, who led the research at the National Observatory in Athens, said he believed it was the first scientific study of art for clues to climate variations.
The scientists studied works painted around the times of major volcanic eruptions, such as the cataclysmic explosion of Mount Krakatoa in 1883, to measure how much pollution was pumped into the skies. Contemporary accounts describe brilliant sunsets after Krakatoa erupted.
“The initial idea arose from the fact that we saw an increased reddening of colors in sunsets which followed large volcanic eruptions, particularly Krakatoa,” Zerefos said.
By measuring the amount of red and green in the paintings, the scientists aimed to calculate the amount of dust in the atmosphere. The greater the pollution, the redder the sunset, Zerefos said.
Skepticism about method
But Kevin Trenberth, who heads the Climate Analysis Research Center at the National Center for Atmospheric Research in Boulder, Colo., and who is not connected to the study, warned that artists and scientists do not necessarily see sunsets the same way.
“Painters are not scientists trying to do an accurate picture of nature,” he said. “They are artists trying to make something look good or dramatic.”
And James Hamilton, the curator at the University of Birmingham, who has written books on Turner, said that while Turner claimed to paint what he saw, it’s dangerous to put too much weight on an artist’s interpretation.
“They (artists) are not making absolutely clear and accurate records of what they can see,” he said. “It’s very hard to tell when artists are being absolutely accurate and when they’re using vivid sky as a platform to more vivid painting.”
John Thorne, a professor of atmospheric meteorology at the University of Birmingham, who is not connected to the study, said that while there can be a worry about painters taking artistic license, the study deals with that by using a cross section of artists.
“Some artists are very true to nature, some are very true to making up their own story,” Thorne said. “But they’ve used a huge cross-section. So rather than a specific artist, they’re more showing an average across all artists.”
Hamilton agreed, noting: “The more artists and more known dates, the better.”
554 paintings examined
The group examined 554 paintings from 181 artists and categorized 54 of them as “volcanic sunset paintings” because they were painted within three years of major volcanic eruptions.
The volcanic group included paintings by 19 artists, including Turner, Claude Lorrain, John Singleton Copley, Friedrich Caspar David, Breton Jules, Edgar Degas, Alexander Cozens and Gustav Klimt.
The scientists measured the color ratio in all the paintings and found that those with the highest red to green ratio were in the volcanic group.
Posted by SANJIDA AFROJ at 10:37 AM