The future apparently holds less-snowy winters, earlier springs, and hotter summers because of human-produced greenhouse gases, scientists say. Accumulating evidence supports climate scientists' gloomy forecasts. Five of the hottest years measured since modern record keeping began a century ago occurred in the past decade, according to the National Aeronautics and Space Administration. Last year, the year of Katrina and Rita, set records for hurricane activity.
"If you love your children, replace your lights," says Joseph Lstiburek, principal engineer of Building Science, a Boston-based consulting company that specializes in building technology.
The No. 1 contributor of carbon emissions worldwide is the US. It is responsible for 22 percent of the world's annual emissions. In second place, China produces 17 percent, while Russia at No. 3, contributes 6 percent. By another measure, of the top five producers (responsible for more than half of global emissions), the US is by far the highest per capita contributor – 20 metric tons per person per year compared with China's 3.6 metric tons. (Unless otherwise noted, all statistics are from the US Department of Energy's Energy Information Administration.)
But the flip side of these numbers is that, of the top five CO2-producing countries – India and Japan are fourth and fifth, respectively – an individual American can have the greatest impact in reducing carbon emissions.
The best place to start is to reduce electricity consumption. Power plants lose two-thirds of their energy in waste heat. For every one unit of electricity your space heater consumes, for example, two units have been lost at the power plant. This inefficiency is reflected in electricity's cost to consumers. Even though more American homes use more natural gas than anything else, homeowners spend more than twice as much on electricity – $100 billion annually compared with $47 billion. Not only is electricity more expensive, but because of its inherent inefficiency, it contributes 21 percent more CO2 annually than does transportation.