Divorce leaves more than a trail of legal documents, stinging egos and uprooted kids. The split-ups wreak havoc on the environment.

A global trend of soaring divorce rates has led to a surge in the number of households with fewer people. The result: We collectively devour more space and gobble up more energy and water, say the authors of a new study published online this week in the Proceedings of the National Academy of Sciences.

"Not only the United States, but also other countries, including developing countries such as China and places with strict religious policies regarding divorce, are having more divorced households," said co-author Jianguo Liu of Michigan State University. "The consequent increases in consumption of water and energy and using more space are being seen everywhere."

The study gives the down and dirty truths on exactly how much of Mother Nature's resources go down the tubes when unions are severed. But the remedy for such "squander" is made for TV: Fall back in love, or at least cohabitate.

Dirty divorce

Past research by Liu and his colleagues, published in 2003 in the journal Nature, revealed globally the number of households increased more rapidly than actual population growth between 1985 and 2000. "Even in areas with declining population size, we still see a dramatic increase in the number of households," Liu told LiveScience.

Liu and Michigan State colleague Eunice Yu thought divorces could perhaps reconcile the anomaly. They analyzed global household data for both divorced and married homes in 12 countries between 1998 and 2002. The countries included the United States, Brazil, Costa Rica, Mexico, South Africa, Greece and Cambodia, among others.

Though China wasn't included due to lack of relevant data, the authors suggest the same trend occurs there. "Even in China, where divorce was traditionally uncommon, divorce rates have recently surged," they write. They add that 1.9 million Chinese couples divorced in 2006, compared with 1.6 million in 2004.

Results showed on average there were 27 percent to 41 percent fewer individuals living in divorced households compared with married ones. Between 1998 and 2002, divorces in the 12 countries studied accounted for 7.4 million extra households.

In 2000, divorced households ranged from 16 million (15 percent of the total households) in the U.S. to 40,000 divorced households in Costa Rica, or about 4 percent of the total.

Environmental footprint

No matter how many people live in a home, the extra house itself requires resources to construct it and takes up space. It requires fuel to heat and cool. A refrigerator uses roughly the same amount of energy whether it belongs to a family of four or two, as an example.

Analysis of U.S. data for 2005 showed that divorced households used an extra 73 billion kilowatt-hours of electricity and 627 billion gallons of water compared with married households.

The researchers also compared married households in the United States with households that had weathered divorce and remarriage: The environmental footprint rose, then shrank back to that of married households.

Other lifestyle trends that impact family living structures include the demise of multigenerational households, and people remaining single longer, the researchers concluded.

The results, Liu said, indicate another lifestyle trend needs to be taken into consideration in environmental strategies.

"People have been talking about how to protect the environment and combat climate change, but divorce is an overlooked factor that needs to be considered," Liu said.

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