Not too long ago, the only eco-conundrum most of us faced on a regular basis was when the grocery store bagger would ask, “Paper or plastic?” A lot has changed: the world is getting warmer, weather patterns are getting wackier, oil is getting scarcer, and those pesky eco-conundrums are more confusing than ever. Does the energy saved by a new, efficient refrigerator outweigh the waste of tossing out my old one? Isn’t it just as effective to diligently turn off my household lights as it is to invest in costly CFL and LED light bulbs? What should I do if I can’t afford a more fuel-efficient car? (Answers, respectively: yes, no, and read on.) Finding commonsense answers to these kinds of questions was the impetus behind the new book Cooler, Smarter: Practical Steps for Low-Carbon Living, authored by a group of energy experts from the non-profit Union of Concerned Scientists. “There’s a lot of ‘noise’ out there, a lot of conflicting advice when it comes to addressing climate change and cutting your own carbon footprint,” says senior energy analyst Jeff Deyette, a contributing author. “We dug deep and really …