As we mark Earth Day today amid growing concern over global warming, one seeming bright spot is the promise of computers and the Internet to deliver a cleaner economy based on information rather than raw materials.
That was the gist of a 2004 article in the journal Environmental Science and Technology in which University of California, Berkeley, researchers Michael W. Toffel and Arpad Horvath analyzed paper and Internet delivery of The New York Times to readers in Berkeley. The pair found that the environmental case for Internet news was a slam dunk, confirming what was apparently obvious.
Yet for me, the article raised more questions than it answered.
How, for example, could the authors write that Internet delivery of the Times saved paper, yet fail to address the significant increase in per capita paper consumption during the computer age?
Soon, I was trailing a white 2004 GMC 450 truck as it left a printing facility in Concord, Calif., loaded with nearly 9,000 copies of the Sunday New York Times.
I followed the driver, 26-year-old Marcio Santos, as he headed west on California Route 4 for a drop point in El Cerrito, where the papers would be picked up for final delivery to Berkeley. What I found was not what we've been led to believe.
Let's begin with the idea that computers and the Internet save paper.
It hasn't quite worked out. When the first personal computer - an IBM PC - hit the mass market on August 12, 1981, per capita U.S. paper consumption was approximately 560 pounds. In 2006, the figure was about 670 pounds, according to the American Forest and Paper Association.
The explanation is in part that while digital technologies save paper in particular cases, they also facilitate paper use.
"The World Wide Web, far from decreasing paper consumption, served to increase the amount of printing done at home and in the office," Abigail Sellen and Richard Harper observed in their 2002 book, The Myth of the Paperless Office.
In addition, paper consumption is increasing rapidly in Asia because of industrialization made possible in part by computers and the Internet. These technologies allow companies to communicate with overseas factories and track inventory over vast distances. Remote manufacturing increases the energy required to send goods to market.
And remote manufacturing corresponds with the overall growth of outsourcing. Princeton University economist Alan Blinder, former chairman of the Board of Governors of the Federal Reserve, warns that 30 million to 40 million U.S. service jobs will be outsourced because of modern telecommunications.
Then there's the increased use of computers themselves. A 2004 article in Environmental Science and Technology by Eric Williams of United Nations University found that the amount of energy required to manufacture a desktop computer was so great, and the machine's lifespan so short, that "over the life cycle it is probably the most energy intensive of home devices aside from furnaces and boilers."
Mr. Williams noted that computer manufacturing requires large amounts of water and a variety of chemicals, many of them toxic. As of 2006, 1.75 billion Microsoft-powered PCs had been sold worldwide, according to market researcher Gartner Inc.
Finally, there is the energy used to deliver the news. The conventional wisdom holds that sending electronic data requires little if any power compared with paper delivery. But interviews with Mr. Santos and the other men and women who deliver the Times told a different story.
The deliverers provided details on the types of cars they drove and the miles they traveled each night to deliver the paper. Although the deliverers' cars were not the most fuel efficient, and although they drove about 575 miles each night combined, automobile fuel efficiency data and electricity statistics show that it likely took at least twice as much energy to deliver the news electronically.
This is because electricity, our leading source of global warming, is surprisingly inefficient. Also, each online reader will require additional power to keep the computer and Internet connection running. In contrast, once information is delivered on paper, that paper can be passed from reader to reader using no additional energy. The Audit Bureau of Circulations, which measures newspaper circulation, reports that about four people read each copy of the Times in Berkeley.
Of course, Mr. Toffel and Mr. Horvath are correct that production of newspapers is an energy-intensive process. But my research shows that in the delivery phase, electronic news uses more energy - and traditional means of delivery use less - than most people would assume.
As global warming grows more severe and its consequences more evident and alarming, it's time for a hard look at digital technologies and our energy-intensive economy as a whole.
Dusty Horwitt works for a nonprofit environmental organization in Washington. His e-mail is email@example.com.