Unless you've been summering in Antarctica, in which case you experienced the phenomenon firsthand, you've seen the news coverage indicating that global warming is now considered a serious issue.

Scientific studies, such as the prestigious and conservative Intergovernmental Panel on Climate Change 4th Assessment Report, point to human activity as an undeniable contributor.

Even Doubter-in-Chief President Bush mentioned global warming concerns in his State of the Union address. It seems you have to be a member in good standing of the Flat Earth Society to doubt the human effect on the Earth's climate.

The scientific consensus is that the release of greenhouse gases through the consumption of fossil fuels causes global warming. Like every industry, IT plays a part in this process. And as a growing industry, IT will be consuming more and more, and therefore contributing more and more to global warming and other types of environmental degradation. Just consider PCs. Gartner estimates that in the next three years, 400 million will be replaced worldwide. That's a lot of plastic, glass, metals and chemicals to dispose of, with all of their attendant environmental effects.

It can be argued that IT helps other industries reduce their resource consumption by making, say, petrochemical processes more efficient. And IT makes it possible for people to work remotely, cutting down on resource consumption by individuals. Although I can't prove it, I believe that without IT, the effects of climate change would be worse today, and much worse in the near future.

But let's not delude ourselves. Computers and networks come with environmental costs. IT devices can be resource-intensive to produce and difficult to dispose of properly.

It's time to add environmental factors to the total cost of ownership calculation for every IT hardware purchase. Right now, when IT buys gear from vendors, neither party gives much thought to the environmental after­effects. Can you imagine being compelled to upgrade to a new car every five years and then having to either give the old one away or pay someone to take it because its net value was effectively zero and it required special handling to recycle? That's the situation CIOs are in with hardware.

But imagine if IT executives started to include environmental issues in TCO. They not only would ask how energy efficient a vendor's devices are but would also demand specifics on the disposal of the gear at the end of its useful life. They might even probe as to whether the widgets under scrutiny were produced in an environmentally sound manner. The answer might not be a deal breaker (and let's face it, many an IT vendor's sales force would be clueless about how the gear they peddle is put together), but just asking such questions would send a message to high-tech manufacturers: All other things being equal, I will choose the more environmentally conscious company.

By and large, CIOs do a pretty good job of minimizing the environmental effects of their IT assets. Today's tight budgets actually help here, since you buy technology only when you need it. But beyond that, many of you pay for the proper disposal of old computers. Some of you donate hardware to nonprofits and schools. Others offer obsolete gear to employees. A large number of you hire asset-disposal firms to recycle your stuff. To me, that sounds like the "reduce, reuse, recycle" credo in action.

One more action - making hardware's environmental effects part of your TCO calculation - seems like a logical and necessary step. It's time to take it.