Scientists estimating ice-sheet shrinkage and subsequent sea-level rising would occur in the next century believe the phenomenon is happening now, glaciologist Richard Alley said during a lecture at USC.
"They said the ice sheets are shrinking and they’re putting water into the ocean and part of it is because of global warming," Alley said. "They’re 100 years ahead of schedule."
During the April 23 lecture, Alley and fellow scientist Veerabdran “Ram” Ramanathan were awarded the 2009 Tyler Prize for Environmental Achievement. Tyler laureates are honored for focusing worldwide attention on environmental problems and creating solutions.
Both scientists had warned of climate change in the deep ice sheets in West Antarctica and Greenland, and the upper atmosphere. USC administers the prize, including gold medals and $200,000 cash awards. The effort is housed in USC College.
Michael Quick, executive vice dean in the College, hosted the 36th annual awards ceremony.
“USC is very proud of its role in the Tyler Prize administration,” Quick said. “The executive committee of the Tyler Prize has done an outstanding job in selecting the laureates this year.”
The two, he said, “are being recognized for their scientific contributions advancing understanding of how human activities influence global climate, and alter oceanic, glacial atmosphere phenomena in ways that adversely affect the Earth.”
In 2007, the Intergovernmental Panel on Climate Change (IPCC) declared that ice sheets in the Antarctic and Greenland are shrinking faster than anticipated, said Alley, Evan Pugh Professor of Geosciences at Penn State Univerisity.
Exactly how fast to cause a dangerous sea level is still unknown.
“I don’t believe this could happen faster than centuries, but we might in the next decades reach the level that would commit us to this [inevitability] over centuries,” he said, pointing to a screen showing a large map of the East Coast with land submerged.
Alley and Ramanathan are contributing scientists with IPCC, the United Nations network of scientists that shared the 2007 Nobel Peace Prize with former Vice President Al Gore.
About a decade ago, Alley studied a two-mile long ice core pulled up from the center of Greenland revealing the Earth’s atmosphere over 100,000 years. The ice sheet showed that in the past, global climate had drastically changed in as little as 10 years.
Larger, faster changes in ice sheet flow make an abrupt climate change more likely.
“If you’re worried about tipping over the canoe and having a tipping point, if you lean really slowly and carefully it’s not as likely to tip than if you go really fast and hard,” he said.
Shifting to renewable energy sources and becoming carbon-neutral can fight climate change, he said. The cost of converting to a carbon-neutral system would be the equivalent of 1 percent of the world economy per year.
“We would be wise to start investing now to head off climate change,” he said, criticizing those who insist scientists find more proof before committing to spending money on carbon-neutral systems.
“In fact, we don’t do that with anything else in the world,” Alley said. “You don’t pass the budget unless you’re absolutely positively sure about what the economics are going to do. The uncertainties in the models that I’ve seen tend to say invest more now because the model buys insurance against what’s coming.”
Ramanathan, a leading atmospheric scientist, was among the first to show that ozone-depleting aerosols aggravate the greenhouse effect. In 1980, he correctly predicted that global warming from carbon dioxide would be detectable by the year 2000.
“The blanket of manmade greenhouse gases that are already up there is thick enough to warm the climate beyond the threshold level for iconic changes to the climate system,” said Ramanathan, Victor Alderson Professor of Applied Ocean Sciences and Distinguished Professor of Climate and Atmospheric Sciences in the Scripps Institution of Oceanography at the University of California, San Diego.
“The bottom line is there is a way to get out of this mess. I have a way.”
He urged countries to work collectively, noting that it takes air only three to five days to travel across China into the United States — air containing billions and billion of pollutants.
“So as the Chinese are giving us their gift, we are passing along our gift to Europeans,” he said. “From Europe it goes on to Asia. We can’t solve the problem by pointing fingers at each other. We’ve caused the problem collectively and we have to solve it collectively.”
In March, Ramanathan launched Project Surya (Sanskrit for sun), which will give about 3,500 solar and other clean energy cooking devices to families in the Himalayas. He will chronicle the atmospheric soot as a result of the smokeless devices.
If Project Surya expands to hundreds of millions across the world, Ramanathan believes carbon dioxide emissions — and consequently global warming — could be controlled.
“What is my motivation?” Ramanathan asked, before pointing to a slide of himself holding a baby girl with big brown eyes. “That is my granddaughter. She may be thinking that my grandpa is leaving the problem for me to solve. I hope we don’t do that.”