Will it be lost on the presidential candidates that the Pennsylvania primary is on Earth Day, April 22? We have campaigns falling all over each other trying to be "carbon neutral" by buying carbon offsets and showing they can fight global warming, but what about in the debates? Pennsylvanians are clearly thinking about the new energy future and what global warming will bring. But have any of the candidates brought those issues to the forefront?

With its vast coal resources, Pennsylvania has more at stake in the global warming debate than many other states. Pennsylvania emits 1 percent of the world's greenhouse gases -- more than 105 developing nations -- so it is a big contributor to climate change.

According to a recent poll, four of five Pennsylvanians say they are concerned about global warming. Some 96 percent believe it's important that businesses and consumers increase their use of alternative energy sources, such as wind, solar and low-impact hydropower.

This past fall, Congress passed a modest energy bill that forced auto makers to increase fuel efficiency, created a timetable for phasing out the incandescent light bulb and created a small pool of capital to implement a "green jobs" program. Clean-energy legislation in the Pennsylvania Legislature would provide for energy conservation; it includes $200 million for solar energy and $850 million for green energy and green jobs.

These are a good start. But we need true leadership from our next administration and real long-term solutions.

The popular approach (60 percent to 80 percent reductions in greenhouse gases at a future date) is unacceptable; it would continue our coal dependency with the promise of future change. Once carbon dioxide from coal is put in the air, we cannot take it back.

There are really only three ways to reduce our emissions: a moratorium on new coal-fired power plants (and a phase-out of existing plants); massive investment in renewable energy and a requirement that all buildings be "carbon neutral" by 2030. Congress must alleviate the disproportionate effects of climate change on our poor and middle class while giving everyone a chance to benefit from the new green economy and to keep American business thriving.

It's a tough agenda, but it needs to be taken seriously. It's time to start retooling the state's environmental economy to look toward the future. Pennsylvanians must call for the creation of environmentally sensible, economically viable green-collar jobs in renewable energy, alternative fuels and green construction.

There is no longer doubt that global warming is happening, or that we must act now to combat it. A report by the Intergovernmental Panel on Climate Change says with scientific near-certainty that the burning of fossil fuels has increased the concentration of heat-trapping greenhouse gases in the atmosphere. The report has a dire prediction: Annual average temperatures could go up by 3 to 7 degrees Fahrenheit this century if this trend continues.

It's time to get this issue into the spotlight. Last year, the presidential candidates answered almost 2,700 questions from top network reporters, but only three about global warming. This Earth Day, primary election day in Pennsylvania, it's time to change the forecast for global warming.

In the days before April 22, Pennsylvanians should demand that the candidates put climate change at the top of the national agenda -- and then vote, in part, based on the candidates' environmental records.