The record snows across the United States this winter may be seen as a harbinger of the extreme weather expected from global warming, but figuring out how much the planet is warming and what the impact might be will take long-term studies.

The Long-Term Ecological Research project, started by the National Science Foundation in 1980, is doing just that, with 26 sites, most located in the U.S., collecting data related to climate change. And at a symposium in Washington, March 2, seven researchers will present results from a sampling of LTER projects.

These will include studies of ocean acidification, the urban response to climate change, and the effect of global warming on snowpack and water availability in western states and on grassland ecosystems, said Scott Collins, the lead organizer for this year's half-day symposium.

"We wanted to cover the breadth as best we could," Collins, a professor of biology at the University of New Mexico who works at the Sevilleta, N.M., site, told LiveScience.

One of the featured projects is to generate scenarios for the future of forests in different parts of the United States in light of climate change, land-use changes and other factors. That project, which is just getting started, would involve LTER sites in forested New England, the Southeast, the upper Great Lakes states, the Pacific Northwest and Alaska, according to Thomas Spies, a research ecologist with the U.S. Forest Service.

Researchers at those sites would look at data already gleaned on long-term ecological trends and at input from local people and policymakers to generate predictions for the future, Spies said.

The scenarios could be based on the assumption, for example, that forests will be highly protected from development, or that the effects of climate change will be mitigated, he said.

Although projects vary at the LTER sites, which include Antarctic, tropical and grassland locations, research at all of the sites must address questions in five core areas, including the amount of plant material growing in a certain area over a period of time.

Details: The symposium on climate change and long-term ecological research takes place on Wednesday, March 2, from 8:30 a.m. to noon at the National Science Foundation, 4201 Wilson Blvd., Room 110, Arlington, VA.

You can follow LiveScience writer Wynne Parry on Twitter @Wynne_Parry.