December 11th, 2013

Speakers

University Distinguished Professor and Advisor in Marine Studies, Oregon State University

Climate Scientist, Lawrence Livermore National Laboratory

Description 

When environmental scientist Jane Lubchenco served as administrator for the National Oceanic and Atmospheric Administration from 2009 to 2013, the U.S. was experiencing the most extreme four years of weather in its history.

With 770 major tornados, 70 Atlantic hurricanes, 6 major floods, 3 tsunamis, record-breaking snowfall, drought, heat waves and wildfires, climate change started to become part of the conversation.

“I think that that extreme weather actually changed a lot of peoples’ opinions,” said Lubchenco, a marine ecologist at Oregon State University.

Climate scientist Ben Santer pointed to an earlier time in history when climate change came into the picture for researchers.

“After the European Summer heat wave in 2003, the game changed,” said Santer, a scientist at the Lawrence Livermore National Laboratory.

Scientists then began looking at how human intervention in the climate system changes the likelihood of weather events. While some researchers say it’s difficult to connect the dots between extreme weather events and human fingerprints, Santer said it’s clear the fingerprints are there, increasing the intensity of such occurrences.

“The vanguard of science, I think, is looking at how human activities, how human-caused warming of the oceans – the surface, the atmosphere, moistening of the atmosphere – is changing the likelihoods of those kind of threshold-crossing events,” Santer said. “And there is recognition that we now, as scientists, may confirm statements on how we're changing those likelihoods.”

Lubchenco used a baseball analogy to describe human-caused climate change: When a baseball player starts taking steroids, there's a much greater chance he's going to be hitting lots of home runs...you can't point to one particular home run, but the pattern of more and larger is attributable to his taking steroids.

“I think a lot of people have difficulty wrapping their minds around some of the language that scientists use to describe events like this,” Lubchenco said. “We're honoring Steve Schneider tonight and he was one of the champions of trying to find the right analogies to describe things.”

Santer talked about how computer modeling has shown that global warming will lead to more intense hurricanes and typhoons, but Lubchenco said heat waves are one of the most damaging natural disasters.

“I think there is increasing evidence that the very, very large heat waves that we are seeing, we expect to be seeing more of those and lasting longer,” she said. “And I think the attribution for those is stronger.”

When Santer was asked what he says to people who deny climate change because it’s cold outside, he replied, “That’s a phenomenon we climate scientists refer to as winter.”

“There seems to be this incorrect expectation that as human-caused burning of fossil fuels has increased levels of carbon dioxide and other heat-trapping greenhouse gases in the atmosphere that we expect each year to be inexorably warmer than the previous year and we expect winter to go away,” Santer said. “That never was our expectation.”

When Santer testified in front of Congress in 2010, he first heard the contrived narrative that global warming had stopped. Because the claim didn’t have any actual scientific evidence, Santer described it as “science by eminence of position.”

The sea ice in the Arctic has been melting at a rate much faster than was predicted, and with the ocean absorbing more of the heat’s energy, it could impact the path of the jet stream and change the temperatures in the U.S., according to Lubchenco.

“We know that the Arctic has an influence on the rest of the planet but we're just beginning to tease out all the ways in which that's playing out,” she said.

Unfortunately, predictions about the jet stream are only based on computer modeling, rather than clear observational data.

“That would be terrific if we had that baseline for understanding what's happening to this very important large scale ocean circulation, Santer said. “Our best understanding though is that we're not likely to see some catastrophic collapse in this circulation as was portrayed in The Day After Tomorrow.”

Lubchenco expressed concerns about global warming’s disruption of food supplies and national security.

“I think that for a long time, folks thought fairly naively that ag was no big deal because planting zones would just move toward the poles and everything would be fine,” Lubchenco said. “But I think there's increasing reason for concern because of droughts, changing precipitations, changing patterns of precipitation and heat waves and those are wreaking havoc with the food supply, food-growing regions."

During the audience Q&A, Lubchenco was asked about international organizations and cooperation to access and influence climate change.

“One of the real challenges that I faced when I was at NOAA that is only becoming worse is that there is some suspicion by some members of Congress that anything that's international is bad,” she said.

But both speakers also expressed hope for the future.

“People who never would have listened to me – even five years ago – are now willing to give me 30 minutes of their time to listen to the science,” Santer said.

“This makes me hopeful: Climate One,” he said. “This is a safe place where people with very different perspectives on the science and the solutions can have a discussion.”

Lubchenco was hopeful about the social shifts that are starting to emerge.

“Many more people are beginning to see climate not as an economic issue, not as a political issue, but as a moral issue – not only our obligation to other people in the world but to future generations and to all of life on earth,” she said. “Changing the way we think about the problem, I think, is part of the solution.”

“It's just frustrating that we aren't farther along because we see that there is real urgency in moving ahead with this.”

- Danielle Torrent
December 11, 2013
Photos by Ed Ritger
The Commonwealth Club of California