It's a big holiday weekend here in the U.S., so there's a good chance that before or after reading this, you'll be driving around lost. If you are a man, you'll have avoided asking for directions, burning more fuel than would a woman driver. Which means, as a number of researchers are noticing, that differences between the genders are a factor in global warming.
According to this new survey of the cost of driving-while-lost, male pig-headedness each year causes the average male British driver to waste 20 miles' worth of gas more than does his female counterpart. And this 2008 study (click on "abstract in English" unless your Swedish is up to par) found that men in Sweden use a lot more energy in their day-to-day lives than women. Moreover, men's productive activities had higher "energy intensity"—each Swedish kronor they added to the economy required more energy than a kronor generated by women.
The British study just asked about 1,000 people about their driving habits, and extrapolated from there. But the Swedish work, by Annika Carlsson-Kanyama and Riitta Räty for the Swedish Defence Institute, was pretty rigorous. Their analysis found some striking differences: Single women with no kids used 20 percent less energy to lead their lives than did equivalent men, for instance.
What's going on here? According to Maria Alm of the Swedish Energy Agency (pdf), men use a lot more energy for transportation than do women. They drive more (sometimes refusing to ask for directions, no doubt, but also because they like cars, and they eat out and go to bars more than do women). Men also spend more time surfing the web and playing videogames, which is a far-from-trivial part of their carbon footprint: According to the IT-analysis firm Gartner, annual greenhouse-gas emissions from the use of digital technology (phones as well as computers) are now equal to what's produced by all the world's airlines.
Unsurprisingly, report our Swedish friends, men on average are less concerned about climate issues than women are, and are less likely to take energy-saving measures. Could be a subtle psychological difference. But maybe it's just self interest.
Gender also affects energy use in the non-rich nations, where the majority of humanity lives. Men in many developing nations often have more access to electricity and fossil fuels. They're reading by electric lights, and moving heavy objects on motorcycles. So it's women who have to spend muscle power gathering wood, dung, and charcoal—as is discussed, for instance, in this report on women's empowerment in the Philippines (pdf).
Moreover, when women, who do most of the cooking, have to burn wood or dung in their kitchens, they end up inhaling more pollutants. The health consequences are dire, as you can read in this World Bank report (also a pdf). I'm not sure why the Swedes are so up on these questions, but they're clearly onto something.