SU professor discovers a potential new way to study climate, and finds himself ... - Syracuse.com

John Berry / The Post-StandardZunli Lu holds a remnant of ikaite in his lab at Syracuse University. Samples of the same mineral deposit were recovered from the Antarctic Peninsula in 2007, then measured for their oxygen isotope composition. This research was used to reconstruct the environment that was in existence at the time the material was deposited. His article was published in a peer-reviewed scientific journal in April.

Syracuse, NY -- When Zunli Lu published a recent research paper on the composition of ancient crystal sediments found in Antarctica, the Syracuse University earth sciences professor did not imagine he’d become a central character in the global debate over global warming.

Then the political climate changed.

Within a matter of days, Lu found himself being hailed by climate change skeptics across the world as the scientist who had proved their case â€" that man-made global warming is a myth.

Only one problem: Lu says the skeptics’ conclusion wasn’t true.

“The article was a 100 percent surprise,” Lu wrote Tuesday in an email, about a report in Britain’s Daily Mail tabloid, which announced that his research debunked the notion that global warming stems from man’s burning of fossil fuels.

Not only was Lu surprised, he grew distressed over what he views as misrepresentations of his work by media outlets with an anti-global warming agenda. Last week, he took his complaints public, issuing a statement on SU’s College of Arts and Sciences web page.

“It is unfortunate that my research. .. has been misinterpreted by a number of media outlets,” Lu wrote. “Our study does not question the well-established anthropogenic warming trend.” (“Anthopogenic” means “man-made.”)

So what caused the storm?

Blame it on ikaite, a rare crystal of calcium carbonate that starts to decompose at around 39 degrees Fahrenheit. Lu calls it “an icy version of limestone.”

The controversy began March 21, after an SU news release noted that Lu’s research paper, “An ikaite record of late Holocene climate at the Antarctic Peninsula,” had been published in the online journal Earth and Planetary Science Letters. The paper described the discovery of ikaite mineral crystals in the Antarctic and their potential for climate-related studies.

After analyzing sediment cores, Lu and his team found that the ikaite crystal contains information about temperatures present long ago, when the mineral formed. They are the first to prove that ikaite can be a tool for studying past climate conditions.

By dating the ikaite from a drill core, the authors concluded that the Medieval Warm Period (10th and 11th Centuries) and the Little Ice Age (17th Century) â€" two well known historical climate fluctuations in Europe â€" extended to a location in the Antarctic Peninsula.

Or, as he told the SU news services department: “We showed that the Northern European climate events influenced climate conditions in Antarctica.”

That’s where the bloggers began. They contended that Lu’s work proves the Medieval Warm Period was a global phenomenon. Because carbon dioxide emissions back then were a tiny fraction of what they are today, the skeptics argued that Lu’s paper proves the planet goes though heating and cooling periods, regardless of human activities. Thus, they said, global warming proponents have it wrong.

On the web, Lu’s research became a rallying point for global warming skeptics. This was amplified with an article in the Daily Mail, a British tabloid, under the headline, “Is this finally proof we’re NOT causing global warming? The whole of the Earth heated up in medieval times without human CO2 emissions, says new study.” Later, Fox News ran a summary titled, “Study Refutes Manmade Warming.”

Lu said his work posed no such conclusions.

“The scope of our research was not to try to find a cause for the Medieval Warm Period or the Little Ice Age in Northern Europe, but to determine whether we could get a reliable signal of past climate conditions from the mineral ikaite,” Lu said in the email. “We successfully did that. Furthermore, our research was not designed to determine the causes of current climate change.”

Lu stressed that his findings focused on one site. “The results should not be extrapolated to make assumptions about climate conditions across the entire globe,” he said.

The professor said he sent a message to the Daily Mail through an online feedback system, after he couldn’t contact an editor. He has not yet received a reply. The online article has changed from earlier drafts, perhaps due to his concerns, but the headline remains.

“I hope and I think the issue has been put to rest,” Lu said. “I never perceived that our paper would be controversial.”