Obama's Top Science Adviser to Congress: Earth Could Be Reaching Global Warming ‘Tipping Point’ That Would Be Followed by a Dramatic Rise in Sea Level
“Climate scientists worry about ‘tipping points’ in the climate system, including ecosystems, meaning thresholds beyond which a small additional increase in average temperature or some associated climate variable results in major changes to the affected system,” Holdren told members of the House Select Committee on Energy Independence and Global Warming.
Holdren, who testified on the current state of climate science and submitted written testimony, presented the points of no return.
“Examples of tipping points of eventual concern include the complete disappearance of Arctic sea ice in the summer, leading to drastic changes in ocean circulation and climate patterns across the whole Northern Hemisphere."
Another possibility he laid out was that ice sheets in Greenland and Antarctica would begin losing mass more rapidly “driving rates of sea-level increase that could reach 6 feet per century or more.”
But Holdren, who was the director of the Woods Hole Research Center before being appointed to head Obama’s Office of Science and Technology Policy, caught heat from Republicans on the committee for the prediction.
Rep. James Sensenbrenner (R-Wis.), the ranking Republican, pointed out that Holdren had previously cited 13 feet as the figure for possible sea level rise by the end of this century--a figure far higher than the one released by the United Nations a year later.
“You gave an interview in August of 2006 with BBC News in the UK and you said that a sea level rise of up to 13 feet was in the realm of possibility,” Sensenbrenner told Holdren. “However, that’s 11 feet higher than what the IPCC (United Nations Intergovernmental Panel on Climate Change) has estimated over this period of time, which is somewhere between seven and 23 inches.”
Holdren answered that, like his current claim of 6 feet, the previous estimate was based on his reading of the scientific literature.
“That was based on scientific peer-reviewed publications that appeared in the early 2000s that indicated that over geologic time in periods of natural climate change, there had been episodes in which the sea level rise increased by as much as 2-5 meters per century, and that this could not be ruled out at the temperatures for which we were heading in the 21stt century as a result of our activity,” Holdren said.
Critics say “tipping points” are scare tactics to bring weight to their conjectures.
Steve Milloy, the president of the environmental consulting group, Steven J. Milloy Inc., told CNSNews.com that the notion of “tipping points” is trendy, but unfounded.
“I don’t even know what that means; I mean, it’s a ridiculous concept,” he said.
“There’s no such thing as a tipping point. How do we know that? We know that we’ve been coming out of the Little Ice Age for the last 200 years. How do we know that we’re not headed into another period like the Medieval Optimum -- which was very warm?”
Milloy, who founded the popular Web site, JunkScience.com, to highlight what he claims are poor scientific analyses of global climate change, said the forecasting models scientists use to make ify "tipping point" predictions of catastrophe are faulty.
“The models are all wrong,” he said. “And why are they wrong? Well, they’re based on the unproven assumption that man-made CO2 drives climate.”
“(Holdren and others) are worried about the temperature going too far and that if we get a degree warmer somehow the world is going to turn upside down.”
An Unscientific Trend in Science?
In fact, Holdren is far from alone in his notion that there are approaching “tipping points” for the earth’s climate. A survey of scholarly publications shows a number of journal articles addressing the concern.
-- In 2005, the Journal of Climate published “The thinning of arctic sea ice, 1998-2003: Have we passed a tipping point?” while researchers at the University of Oregon predicted in 2008 that a tipping point for the health of the Southern Ocean ecosystem would be reached when CO2 levels in the atmosphere reached 450 parts per million.
-- Jim Hansen, director of the NASA Goddard Institute for Space Studies, testified before the same House Select Committee in June that “ominous tipping points” loom regarding the Greenland and Antarctic ice sheets.
-- Holdren himself has used the “tipping point” idea before in his confirmation hearing before the Senate in February, while he described another dramatic prediction of his -- that one billion people could die from carbon-caused famines over a 34 year period.
Sen. David Vitter (R-La.), a top Republican on the Senate Commerce Committee, called Holdren's hand over the prediction, asking the nominee: “In 1986, you predicted that global warming could cause the deaths of one billion people by 2020. Would you stick to that statement today?”
Holdren said it was unlikely, but that “I think it could happen, and the way it could happen is climate crosses a tipping point in which a catastrophic degree of climate change has severe impacts on global agriculture. A lot of people depend on that.”
Vitter followed up, asking, “So you would stick to that statement?”
“I don’t think it is likely,” Holdren said. “I think we should invest effort --considerable effort -- to reduce the likelihood further.”
Claims such as these are evidence that Holdren is a “huge alarmist,” according to Milloy.
“A thousand years ago the Vikings farmed Greenland. What was the Arctic ice shrinkage then, in the summer? I imagine it was pretty extensive and there were no SUVs or coal-fired power plants back then,” Milloy told CNSNews.com
Milloy said the models used by climate scientists, especially those who contributed to the most recent United Nations IPCC report, do not take account of some huge factors -- including the sun and clouds.
“The models exclude that big yellow ball in the sky and they also exclude those white fluffy things that float by,” Milloy mocked. “Both of those have dramatic effects on climate on a daily basis.”
Meanwhile, a series of leaked e-mails from the University of East Anglia’s Climate Research Unit between climatologists now known as “Climategate” show that there is not enough understanding of all of the impacts on climate to make such dramatic predictions.
“If you look at those Climategate e-mails,” Milloy said, “Kevin Trenberth, who’s a very senior IPCC scientist, admits that he does not understand energy flows in the atmosphere. Well, if you don’t understand energy flows in the atmosphere, then you can’t model those energy flows and you can’t make those crazy predictions--and you ought not make global energy policy based on something you don’t understand.”
Trenberth, a contributor to the last U.N. report, is also head of climate analysis at the National Center for Atmospheric Research.
According to e-mails that are part of the Climategate leak, Trenberth allegedly told colleagues in 2004 that “we are nowhere close to knowing where energy is going or whether clouds are changing to make the planet bright. We are not close to balancing the energy budget.”
Trenberth said that “geoengineering,” attempts to change the Earth’s climate, should not be attempted.
“The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!”
Meanwhile, more than 140 other scientists wrote an open letter Monday to U.N. Secretary General Ban Ki-Moon, challenging the body to “produce convincing OBSERVATIONAL EVIDENCE for their claims of dangerous human-caused global warming and other changes in climate.”
The signers include Dr. Ian D. Clark, a paleoclimatology professor at the University of Ottawa, and Joseph D’Aleo, first director of meteorology for The Weather Channel.
The group said dire predictions from computer models alone were not sufficiently scientific.
“Projections of possible future scenarios from unproven computer models of climate are not acceptable substitutes for real world data obtained through unbiased and rigorous scientific investigation,” they wrote.