by Michael D. Lemonick

This story was originally published in the Summer 2010 issue of On Earth magazine.

I am often asked to speak to science-journalism classes, and when I do, I usually start off with a question. "How many of you," I ask, "got into journalism to make the world a better place?" Invariably, most of the students raise their hands.

"Not me," I tell them, to general surprise. It's true, though. I admire journalists who see their mission this way. I'm simply not one of them. I decided to be a science journalist because I love learning about how the natural world works, from the subatomic level right up through biology to the planets and the birth, evolution, and ultimate death of the cosmos. Journalism simply gives me a way to make a living at it.

For whatever reason — a big part of it is undoubtedly the fact that my father was a physicist — I'm especially drawn to the physical sciences. I've been writing about astronomy and physics, for example, since my very first week on my first job at the now-defunct Science Digest magazine, in 1983. By 1987 I was working as a writer at Time, and that summer, when a group of climate scientists came to visit the magazine's editorial staff, I was intrigued by the story they laid out for us.

Since the Industrial Revolution began, they said, humans have been burning fossil fuel and, as a result, pumping carbon dioxide into the atmosphere. CO2 is a greenhouse gas — it traps heat. Therefore, the earth's average temperature is likely to rise. The scientists' best guess was that the thermometer would rise by about 8 degrees Fahrenheit by 2100. They acknowledged that this might not sound like a lot. But it would be comparable to the global temperature change that brought the planet out of the most recent Ice Age. And this time it would be happening a lot faster.

I loved this story — it was about the physical sciences, it was clearly a big deal, and it was new and surprising to me. Most important, the science was both straightforward and entirely plausible. My enthusiasm, and that of my editors, led to a cover story in Time in September of that year titled "The Heat Is On." It was, as far as I know, the first major magazine story about what we then called the greenhouse effect. (The story also discussed the hole in the ozone layer, which had just been discovered over Antarctica.)

In putting the story together, I had to figure out how to characterize global warming. It was tempting to proclaim impending doom, which would grab attention and sell magazines. That would make my employers happy, of course. In my time at Science Digest, where Andy Revkin, Elisabeth Rosenthal, and several other prominent environment writers got their start, we did a lot of that. My favorite cover lines included "Spontaneous Human Combustion," "Sex in Space" (I think it involved frogs), and "Space Telescope Sees to the Edge of the Universe! Ten Pages of Pictures" (a story about the Hubble, years before it was launched, with pictures of the telescope being assembled).

I was now working at a more responsible magazine, though, and at that point climate change was only a potential threat. There were no definitive measurements showing that the earth was in fact warming or that sea level was rising. This didn't refute the idea, however. Climate is a noisy system, with temperatures and other indicators wobbling up and down around an average value. The signal of climate change would be too small to see against this noise, even if it was there.

It wasn't long, however, before the signal did emerge from the background noise, in the form of temperature increases, sea level rise, glacial retreat, and dozens of other measures. During the 1990s, the skeptics' arguments got weaker and the number of skeptics diminished. "Faced with these hard facts," I wrote in a 2001 Time cover story, "scientists no longer doubt that global warming is happening, and almost nobody questions the fact that humans are at least partly responsible."

The nature of journalism was also changing during that time. Faced with increasing competition from blogs and other online news outlets, newspapers and magazines were starting to move in the direction of shorter, more sensational, and more user-friendly stories. Time was no exception. The magazine upped its personal-health coverage and downplayed serious science. In 2003 for example, it ran a cover story titled "The Secret of Eating Smarter." In 2004 it ran "How to Live to Be 100." (The answer was "eat smarter.")

My growing discontent with the changes in journalism was reinforced by a seminar I'd started teaching at Princeton University in 1999 called "Life on Mars — or Maybe Not." It addressed the interaction between science and journalism, looking at the factors that distort science as it moves from the lab or scientific journal onto the front page. Science journalism demands a certain degree of latitude when it comes to representing the complexities of a particular field: even the most diligent reader is still looking for lively, understandable prose. But in their quest for liveliness, many news outlets started emphasizing worst-case scenarios or looking for the most quotable rather than the most knowledgeable sources. To compound that problem, climate change was becoming a much more sharply politicized story. Slowing down climate change will require government intervention, which horrified advocates of smaller government. And reining in emissions threatened some entrenched economic interests. Motivated by these extra-scientific arguments, some lobbyists, politicians, and think tanks latched on to these non-experts to argue the "other side" of the "climate debate" -- much as the antievolution movement found scientists to support its efforts to teach the so-called controversy over evolution.

Thanks to pressure from climate skeptics, some journalists started adding dissenting voices in an attempt to add "balance" to their stories, even though scientific skepticism about climate change had largely vanished among true experts. It now lies with nonexperts like Freeman Dyson — scientists from unrelated fields who don't know much about climate science but weigh in anyway.

The move toward sensationalism isn't why I left Time in 2007; the magazine does better than most at staying intellectually honest about science. It was because Time, desperate to cut staff costs, had offered an attractive severance package, and I was ready for a change. Not long after I left, I got wind of a new nonprofit being formed in Princeton. Called Climate Central, it was created by climate scientists and philanthropists who were unhappy with the way the science was being conveyed to the public.

Climate Central's mission was to counter the trend by providing stories to existing media that reflected the best available science -- no advocacy, no hype. To do so, Climate Central assembled a team of journalists and scientists who would work together to report significant findings and trends. Sure, it would mean giving up some of the fierce independence that most journalists hold dear, but in light of my growing cynicism about my profession, it sounded pretty great. I managed to get hired.

Since then, I've published stories on behalf of Climate Central in Time, Newsweek, E360, Parade, and other publications. I've tried to live up to the organization's mission -- by reporting, for example, that famed climate scientist Jim Hansen's argument that we must reduce CO2 to less than 350 parts per million to avert worst-case climate scenarios isn't universally accepted by his colleagues; or that the vanishing snows of Kilimanjaro, which Al Gore so eloquently referred to in An Inconvenient Truth, may not be a victim of climate change alone; or that the newly discovered emissions of methane from Arctic subsea permafrost may, but also may not, signal impending doom.

But I've also tried to be clear at all times that the underlying science of climate change is extremely solid, and that much of the hand-wringing over "Climategate" and "Himalayagate" and other recent challenges to climate science is just nonsense. I'm still refining my own sense of judgment, weighing when it's important to give a study's weaknesses prominence and when to mention them on the side, focusing instead on the broader truth that climate change is real and potentially dangerous.

I find this approach to climate reporting to be tremendously satisfying. It lets me craft a short lesson about how science actually works, uncertainty and all. It's not an attempt to sell any one idea; it's an attempt to get at the truth as best I can. I like to think that this sort of journalism will continue to appeal to readers through all of the wrenching changes now going on in the profession, and will be part of what emerges on the other side.

That's the message I try to pass on to my students and to any other young journalists I talk to. The science of climate change, like all of science, is complex and messy, but the truth eventually emerges from the background noise. Watching that happen, and reporting on it, is endlessly fascinating and important and fun. If the world ends up being a better place as a result, that's okay too.