Senator Eliot Shapleigh - El Paso, Texas

We hear how global warming melts ice caps, spikes temperatures and even eliminates species, as Time magazine's cover story for April 13 warns us.

Fair enough, but here's another environmental hazard that deserves our attention: The challenge that climate change presents to water supplies across America, particularly in big states like Texas and California. The biggest concentrations of Americans live in big states, so the greatest damage could be done there if atmospheric changes spawn more droughts.

To imagine this better, dial the clock back to last week's wildfires across North Texas and Oklahoma, which wiped out dozens of homes and spread a yellow-orange haze across Dallas and Fort Worth. The fires weren't necessarily due to climate change, but they do foreshadow the future if droughts become the norm. High winds and dry pastures are masters at stoking wildfires.

Californians know that truth better than anyone. They also know the risks of running out of water. The federal government did the almost unthinkable when it told farmers in the huge breadbasket from Sacramento to near San Diego that they could have no water to irrigate their crops this year.

Let's repeat that: No water to irrigate crops. And that is in the middle of one of America's largest farming belts. Not only does this situation threaten California's farmers and economy, it affects how much the rest of us pay for our food.

The no-irrigation edict results from the state's lack of water. Imagine what would happen with more people living there facing longer and more severe droughts.

Let me stop here: I'm not a doomsayer. I'm not trying to Al Gore us.

In fact, Bill Mullican, a water consultant who managed Texas' water planning for a decade, made a really good point to me last week about climate change and droughts. Some parts of the country, he said, could end up with more water if global warming leads to more big storms. Heavier rains in areas that depend on aquifers like the massive Ogallala, which runs from the Texas Panhandle to South Dakota, could replenish those underground streams more quickly.

Still, as Mullican and others suggest, Americans would be better off planning for the possibility of droughts becoming common. Here's where President Barack Obama could enter the climate change debate in a way no national figure has.

Locals are best at water planning, but Obama and Washington could spur the planning. The No Child Left Behind Act offers a good model. President George W. Bush and the feds didn't tell the states what standards to adopt, but they insisted that states adopt standards for their classrooms.

The same principle could apply to water. Washington could require states to create water plans for the next 50 years and then consult with them about those plans.

To some extent, the Army Corps of Engineers is pursuing this and has asked all states to participate in a survey about their water planning efforts. States and the feds will explore at regional workshops how Washington can help states.

Texas already has a 50-year plan. For the last decade, leaders in 16 regions of Texas have been creating and revising water strategies.

That's good, but now the caution: It does no good to create a plan if you aren't going to finance it. So far, Texas hasn't. Its plan depends largely on the whims of the state's appropriators each budget cycle.

That's why Republican Sen. Kip Averitt's proposal to create a funding pool from the state's Rainy Day Fund is crucial. Texans then would have a way to pay for their plan's needed projects.

Texas legislators have a responsibility to look into the future. So do other states. Ice caps, fluky temperatures and vanishing species aren't the only challenge the atmosphere presents.

William McKenzie is a Dallas Morning News editorial columnist and a moderator of Texas Faith. His e-mail address is wmckenzie@dallasnews.com.