A long-awaited report reveals some disturbing projections of what life in Chicago might be like as the earth warms. And it contains an ambitious plan to confront climate change.

Scientists have been cooking up predictions for years about how climate change will affect the planet. Now, University of Illinois atmospheric scientist Don Wuebbles has come up with a local forecast.

WUEBBLES: It’s not a place I would desire to live. I don’t like the warm days with high humidity now. So imagine the whole summer being like that.

We’re talking more than 30 hundred-plus degree days. Wuebbles integrated global models with the Chicago area’s hundred-year climate record. His algorithm spit out two scenarios: one where everyone cuts back drastically on greenhouse gas emissions, and another where emissions remain high or increase. Neither is pretty for Chicago.

WUEBBLES: Potentially a 1995-type heat wave occurring as much as three times a year. Maybe every other year with a low scenario. Large storm events, the kind of events we’ve seen recently with large amounts of rainfall, are going to become more common. The rate of those could double by the end of the century.

Chicago’s climate action plan spells out how the city might do its part to avoid that scenario. Environment Commissioner Suzanne Malec-McKenna says the problem is much bigger than Chicago but she’s upbeat about making a dent.

MALEC-MCKENNA: We really think we’re gonna lick this. We know regardless of the activities we do, there are going to be some changes in the next 10-20 years. And we’ve already seen that. Our hardiness zone, our planting zone has gone to Champaign-Urbana. But we think we can dramatically slow it down.

The plan sets citywide goals for emissions reductions – 25 percent below 1990 levels within the next 12 years. Close to a third of that would come from making buildings more energy efficient another third from greening the power supply – adding renewables and modernizing old plants. The rest would come from better transportation options and less industrial pollution. Early reviews from environmental activists have been pretty positive. Rebecca Stanfield is a senior energy advocate with the Natural Resources Defense Council.

STANFIELD: I think it is a serious effort to get Chicago on a path where we are addressing our contribution to the global warming crisis.

Stanfield praises the plan for not retreating on the emissions reductions. She also commends planners for laying out in detail how climate change would affect everything from lake levels to public schools’ heating-and-cooling needs. But she says it’s not perfect.

STANFIELD: If I could change one thing about this report, I think the city should take a bolder stand on dealing with the Crawford and Fisk power plants on the south side of the city. Those are old power plants and they really need to be phased out and replaced with something much cleaner.

Change is coming for those two coal-burning plants, though it may not be rapid or drastic enough for critics. Environment Commissioner Malec-McKenna says the plants must modernize or close within the next decade.

MALEC-MCKENNA: Our preference would be to find a way for them to repower and still run that business. We think it’s great to have local power plants, if they’re good for the environment and good for the local economy.

Electric utilities would have to make some pretty major adjustments under the city’s plan as would the transportation sector, construction, and many other businesses. City officials insist that most will save money in the long run. In fact, they’re counting on that to push businesses and citizens to act, since the plan is driven more by goals than mandates. Mayor Richard Daley says he’s confident that cooperation will get the city where it needs to go. He reflected on how far the city has come in two decades and took the opportunity to pat himself on the back a bit.

DALEY: When I became mayor, just a few years ago, no one heard of climate change. The only they thought is, why is the mayor wasting money planting trees?

Much has changed since then in terms of science and political will … but some things aren’t so different: the climate action plan calls for the city to plant another million trees.

I’m Gabriel Spitzer, Chicago Public Radio.