Climate change science, not hype

Last week, NASA announced that 97% of Greenland’s vast ice sheet had undergone at least some surface melting this summer, compared with a normal melt area of about 50%. The 2012 figure, said the headline on the space agency’s press release, was “unprecedented.”

That’s a powerful word in any context, but it’s especially so when you’re talking about the politically charged topic of climate change. If the melting was unprecedented, it would reinforce the idea that scientists are right about the dangers of human-generated greenhouse gases, and at the same time make it harder for skeptics to take potshots at the science.

The skeptics were naturally delighted, therefore, when it turned out that such widespread melting is anything but unprecedented. It happened most recently in 1889, and it happens, on average, every 150 years or so. This summer’s surface melt has very likely been influenced by global warming, but it might have happened anyway. The same goes for the heat waves that have pummeled large parts of the nation this summer and the drought that’s now destroying crops in the Midwest.

The drama and the hype — alarmist headlines, crowing skeptics, backtracking scientists (or at least, publicists) and a confused public — made me crazy. With one poorly chosen word, climate-change skeptics were handed an opportunity to sow more doubt and confusion about global warming.

I work at Climate Central, a nonprofit, nonpartisan research and news organization, and a good part of my work is dedicated to putting an end to just that sequence of events. Our central mission is communicating to a general audience what the science is and what it is not.

For the record: The science clearly shows that climate is changing largely as a result of greenhouse gas emissions. The science is equally clear that without rapid and drastic cutbacks in greenhouse gas emissions, the changes are likely to threaten life, property and Earth’s biosphere in all sorts of ways — including melting glaciers and worsening weather crises — by the end of century, and in many cases, much sooner. In fact, some of these changes are already happening.

But there is a lot science doesn’t know as well, especially what the link might be (if any) between climate change and specific events. It doesn’t know for certain what the future holds for, say, hurricanes. (The tentative conclusion: These storms could become fewer but more powerful.) It can’t say precisely how high sea level will rise, or how fast.

And there are outliers, scientists with (and sometimes without) legit credentials who doubt the mainstream conclusions. Yes, scientific “facts” are mutable: As data accumulate, knowledge changes. But just because science adjusts itself to new information (or because outliers invariably exist), it doesn’t make the mainstream wrong.

I’m not a scientist; I’m a science journalist. I translate the arcane terminology of experiments, data and theories into everyday English. In the current climate of global warming doubt — in which any uncertainty is used to discredit mountains of confirming data, where even a typo might promote misunderstanding — the job can be a minefield.

I just co-wrote a climate-change primer for Climate Central: 60 simple, bite-size dispassionate chapters about what scientists know on the topic, no more, no less. Accuracy is always the appropriate goal for a journalist, but for “Global Weirdness,” we were hyper-vigilant.

Each chapter was reviewed, down to the comma, by at least one of Climate Central’s doctorate-level staff scientists, and revised based on their critiques. Each chapter was then re-reviewed by at least one scientist outside our organization, drawn from a list of the world’s most eminent experts, and revised again.

It was something like the peer review process that scrutinizes scientific findings before they are published. No writer (and no scientist) particularly likes to have his or her work picked apart in this manner, but it’s the best way we know to get things right.

This doesn’t mean our work won’t come under criticism. The very fact that we take mainstream climate science seriously will paint us as partisan hacks in the eyes of those who insist the whole thing is a scam, and that includes some scientists with doctorates of their own. And we’ll no doubt also be criticized by those who think we aren’t scaring people enough. Without fear, they believe, people might not take action.

Who knows, the fear pushers might be right. But as convinced as I am that limiting greenhouse gases is important, I’m grateful for every time a critical scientist or editor has stopped me from making an “unprecedented” error.

In the end our best hope is sticking with the science as it is, not as any one person or cause wishes it might be.

After all, the truth is scary enough.

Michael D. Lemonick is a senior writer for Climate Central, a contributor to Time magazine and a coauthor of “Global Weirdness: Severe Storms, Deadly Heat Waves, Relentless Drought, Rising Seas, and the Weather of the Future.”