A fresh look at the latest data on climate change strongly suggests that Utah will be hotter, with drier summers and wetter winters.

The trends are being watched closely by people concerned with the state's water supply. They wonder whether the Wasatch and Uinta mountains will continue to store water reliably in the century ahead.

Climate scientist Thomas Reichler presented the findings of his University of Utah research group on Monday, the day before the publication of a separate, sobering study that says many damaging effects of climate change are already irreversible.

"People have imagined that if we stopped emitting carbon dioxide, the climate would go back to normal in 100 years, 200 years; that's not true," climate researcher Susan Solomon said in a teleconference.

Rather, her group said that even if carbon emissions can somehow be halted, temperatures around the globe will remain high until at least the year 3000.

Solomon, of the National Oceanic and Atmospheric Administration's Earth System Research Laboratory in Boulder, Colo., is the lead author of an international team's paper reporting irreversible damage from climate change, being published in today's edition of Proceedings of the National Academy of Sciences .

She defines "irreversible" as change that would remain for a thousand years even if humans stopped adding carbon to the atmosphere immediately.

Meanwhile, the Utah team is offering the clearest picture to date of how climate change can be expected to affect the mountainous north and the desert south regions of the state.

Reichler noted that computer analyses have improved dramatically and that their projections are tracking closer and closer to observed changes in climate.

In short, he said, Utah can expect to see about 5 to 10 percent less water in the summer over the next century and a 5 to 10 percent increase in water during the winter.

Summer temperatures will rise around 7 degrees, while winter temperatures will be about 3 degrees warmer. Less precipitation will fall as snow, he said.

How much of that water will evaporate? Will Utah's reservoirs hold enough water? Will snow melt too fast and too early in the spring?

National Weather Service hydrologist Brian McInerney said Reichler raises important considerations for managing Utah's water supply.

"We need to understand what is going on in our backyards," said Jim Steenburgh, chairman of the U.'s meteorology department.

The Associated Press contributed to this report.