If you had asked me that question just a year ago, I probably would have expressed skepticism. I have covered climate change as a science journalist for more than two decades and care deeply about the issue. But I’ve always thought of it as problem to be solved on the national or international level. So, like many people, I have spent a lot of time dismayed that our leaders haven’t been taking action commensurate with what is suggested by the latest scientific evidence, but relatively little time thinking about what I might do about the problem in my own life, thinking—wrongly, it turns out—that my actions were too inconsequential to make much of a difference.

But then my colleagues at the Union of Concerned Scientists asked me to join a project they had already been working on for some time: an in-depth examination of the most effective steps individuals can take to combat global warming. The project has profoundly changed the way I think about the issue. It has opened my eyes to just how easy it is for most Americans like me to make some simple changes to use energy more efficiently and thereby significantly lower our emissions. What’s more, it has shown me what a surprisingly big difference these changes can make when adopted widely.

Reduce your carbon emissions 20% this year

Our new book, Cooler Smarter: Practical Steps for Low-Carbon Living, has just been published by Island Press, the result of UCS’s two years of research on the subject by a crack team that included climate scientists, technical experts, and economists. The book challenges each of us, no matter what our circumstances, to reduce our emissions by 20 percent in the coming year—an achievable and meaningful first step—and it offers a menu of strategies to get the job done. (We’ve even developed a website that you can use to reduce your footprint by 20 percent.)

Cooler Smarter is chock full of information including some surprises about which of our actions matter most (many details about those to come). To get the answers, our experts painstakingly tracked both the direct and indirect emissions resulting from every dollar spent by U.S. consumers, analyzing the climate impact of our decisions on hundreds of topics from home insulation to diet. But let me start by sharing the big picture results.

Your carbon emissions and what matters most

The average American is responsible for emitting a whopping 21 tons of heat-trapping carbon dioxide into the atmosphere annually. To give that number some perspective, that’s more for each one of us than an average car would emit driving around the world at the equator.

On a per capita basis, Americans emit almost four times more carbon dioxide than the global average, and twice as much as citizens do in places like France or Japan with a standard of living similar to our own. That’s a lot of carbon. But here’s the good news: There’s no question Americans can use energy more efficiently—without breaking much of a sweat. Many of the suggestions in Cooler Smarter will save you money, others are great long-term investments, and some will even improve your health. And they are easier to implement than you might think.

The figure to the right shows the breakdown of the Average American’s emissions into five major categories which pretty much boil down to: the car you drive, the way you heat and cool your home, the electricity you use, the food you eat, and the stuff you buy.

You can make a real difference

If you are skeptical that changes in these categories can make a difference (as I once was) consider this: If everyone in the country cut their overall emissions by just 20 percent, it would be like shuttering 200 of the nation’s 600 coal fired power plants. Let me say that again: It would be like saying goodbye to ONE THIRD of our nation’s most-polluting sources of energy which could make an enormous difference to global warming.

But I’ll give you another example of the kind of difference these changes can make that’s a lot more personal. Among my many former wasteful habits, I used to leave the laser printer in my home office turned on 24/7, again figuring that it didn’t make much of a difference. Cooler Smarter has taught me that just hitting that single “off button” on that single one of my many gadgets will save me more than $130 per year on my electric bill. It’s just one of many easy changes I’ve already made on my path to a 20 percent reduction in my emissions that are actually helping my wallet and the planet at the same time.

Cooler Smarter gives you the tools you need to lower your emissions in each of the categories above and also offers techniques to help you inspire your friends, family, neighbors, and coworkers to do the same. Individual action alone can never replace the need to press for changes on the state, national, and international levels. But our leaders won’t be compelled to change unless we as citizens show them we value a low-carbon future and take action in our own lives. In other words, I’ve rekindled my understanding that on this issue, like so many others, we need to work for change from the bottom up and the top down. You can learn more, use our tools to help you reduce your emissions by 20 percent—and pick up a copy of the book —by visiting our website www.coolersmarter.org.