Climate change: Topic at Princeton library March 15

Anthony Stoeckert, Packet Media Group
   If you panic at footage of melting ice caps and fear that our planet is headed toward devastating drought, wildfires and flooding, then Stephen Pacala might be able to put your mind at ease a bit.
   Not that Stephen Pacala — a professor of ecology and evolutionary biology at Princeton University — thinks it’s a guarantee that humans will smarten up and reverse the trend of global warming, but he’s hopeful that things could start changing.
   ”It’s easy, these days, to succumb to despair, and I think it’s important not to,” Dr. Pacala says. “Can I paint a scenario where we don’t take action as a species? Where we aren’t mature enough as a species to take action before we have to do something to geo-engineer the planet? Sure I can give you a scenario that will do that for you.
   ”But I also know that when I travel around and talk to young people, that so many of the smartest ones are working on this problem. And the progress on the technological front is so rapid and so unprecedented and so much in the hands of 24- and 25-year-olds that it really gives me hope that we’re clever enough to save ourselves from our own folly.”
   Dr. Pacala will be appearing at the Princeton Library with science writer Michael Lemonick on March 15. Both men are part of Climate Central (www.climatecentral.org), a Princeton-based organization devoted to researching and reporting on global warming trends.
   The appearance is part of a series of conversations with authors and experts the library has hosted this winter. According to Dr. Pacala, audience members can expect Mr. Lemonick, a science writer who has written for various publications and written several books, to ask Dr. Pacala — the director of the Princeton Environmental Institute — about topics including the seriousness of global warming, and the evidence that’s it’s already here, particularly via extreme weather. They also plan to get the audience involved and asking questions.
   ”We’re entering the era where all of a sudden the damages are clear, so I think the message that it’s already here is an important one,” Dr. Pacala says.
   During a phone interview, Dr. Pacala speaks about climate change-related issues in a friendly, conversational way, which should make the evening informative for non-scientists. When asked if the strange weather we’ve experienced — hurricanes, drought, winters with minimal snowfall — is caused by global warming, Dr. Pacala cites a comparison to Barry Bonds’ home run totals during baseball’s steroids era.
   In his late 20s and early 30s, Mr. Bonds had home run totals in the 30s or 40s. When he was 37 and widely believed to be using steroids, he hit 73. Dr. Pacala notes that while Mr. Bonds almost certainly achieved that total because of steroid use, you can’t point to any single home run he hit and say he hit it because of steroids. Similarly, Dr. Pacala says scientists can’t point to any single storm and say it was caused by global warming, but that it’s clear that climate change as has affected weather patterns.
   He makes another comparison with a more serious topic: lung cancer. Statistics show that nine out of 10 cases of lung cancer are caused by smoking, so there’s a one in 10 possibility that any individual case of lung cancer is not caused by smoking.
   ”You don’t know that any one cancer was caused by smoking, you just know that there’s a high probability,” Dr. Pacala says. “That’s what we’re doing with the climate problem. We can say that there’s a certain probability that an event was caused by climate change, but we can’t assign any one event, unambiguously deterministically, to climate change.”
   Regarding climate-change deniers, who are rampant in conservative media, and can even be found in Congress, Dr. Pacala says that while they get a lot of attention in the media, the majority of Americans believe in climate change. According to “USA Today,” an online survey by Duke University indicated that half of Americans say climate change is definitely occurring and another 34 percent say it probably is.
   ”If you look at the American people, they buy it,” Dr. Pacala says. “So there is a real disconnect between the American people and, for example, Republicans in the House of Representatives.”
   But climate change isn’t the most important issue for most voters, so a lot of people who believe in climate change are voting for candidates who don’t. If someone thinks the economy or national defense are the most important issues, they’ll vote for a Republican if they agree with him or her on those issues, even if they disagree with the candidate’s stance on climate change.
   ”So I can come up with a political scenario where you can push the system over the edge, just not this year or next,” Dr. Pacala says. “On the other hand, the executive actions that the executive branch can now take, put us on a path to de-carbonizing our economy. They don’t finish the job, but they start it.”
   Climate change deniers often point to cold weather patterns as proof that there isn’t global warming. On a recent episode of “The Daily Show,” Jon Stewart summed up their beliefs this way: It’s cold where I am today, so therefore, global warming isn’t occurring.
   Dr. Pacala says that while cold-weather records continue to be set, two records for high temperatures are set for every record low temperature. “In a stationary climate, you’ll get as many cold records as hot records,” he says. “The problem is now it’s two to one, and it will become three to one, four to one, five to one and so on.”
   The deniers also cite scientists who don’t believe in climate change, and while Dr. Pacala says that while those scientists are out there, the overwhelming majority of scientists believe in climate change.
   ”The scientific community is never 100 percent behind anything,” he says. “There were shiny-credentialed people who said that HIV didn’t cause AIDS for a very long time. Lord Kelvin went to his deathbed saying that heavier-than-air flight was impossible because he proved it, and this was after the Wright brothers.”
   Getting back to Dr. Pacala’s optimism for the future, he says that it’s because of young people, and the possibility of advances such as a device that would convert sunshine and greenhouse gases and water into a burnable fuel.
   ”Plants do this, but at low efficiency,” he says. “There’s no theoretical reason why you can’t develop a high-efficiency non-biomoleculed version of the same thing. And somebody who does that becomes the richest person in history and saves the world. So the incentive for the smartest, the most gifted young people is just extraordinary, so it is not too surprising that you find a bunch of them working on it.
   ”If I had to bet, if I had to actually forecast what would happen, my guess is that the species is now clever enough that we’re going to hit on something. It’s nothing like a certainty, it’s just a gut feeling. And not to throw everything we have at this issue is kind of like deciding that you’re going to spend your retirement and go to Vegas when you’re 65 and try to win it all.”
    Michael Lemonick and Stephen Pacala will hold a conversation on climate change at the Princeton Public Library, 65 Witherspoon St., Princeton, March 15. Drinks and light fare will begin at 6:30 p.m. with the talk starting at 7:30 p.m. The cost is $50. Attendance is limited to 50 people. For tickets, go to www.princetonlibrary.org