I believe, within 35 years, our country can and should be 100% powered by clean energy, supported by millions of new jobs. To reach this goal we must accelerate that transition starting now.

As President, on Day One, I would use my executive power to declare the transition to a clean energy future the number one priority of our Federal Government.

I would create a new Clean Energy Jobs Corps to partner with communities to retrofit buildings to be more energy efficient, improve local resiliency, create new green spaces, and restore and expand our forests so they can absorb more greenhouse gases.

I would retrofit federal buildings to the highest efficiency standards and require new federal buildings to be net-zero. I would require the federal fleet to be subject to low- or zero-emissions purchasing agreements, and require all federally-funded infrastructure projects to meet climate resiliency standards.

As President, I would direct the Environmental Protection Agency to take aggressive action to limit greenhouse gases: expanding rules to other large sources of emissions beyond power plants, adopting a zero-tolerance policy for methane leaks from current oil and gas production, and setting higher energy efficiency standards for new buildings while requiring energy costs to be transparent to building tenants and purchasers.

And I would reject projects like Keystone XL, drilling off our coasts and in the Arctic and Alaska. Furthermore, I would keep domestically produced oil and gas in the U.S., instead of selling it abroad — unless there is a clear strategic security rationale.

Beyond executive actions, I would make clean energy deployment – and full employment – a first order priority.

I would set a national, cross-sector Renewable Electricity Standard so our nation is powered by 100% clean energy by 2050, and a national goal of doubling energy efficiency within 15 years. Many states like California and Maryland are already leading the way forward for the United States.

I would fight for federal legislation for a cap on carbon emissions from all sources, with proceeds from permits returned to lower- and middle-class families, job transition assistance, and new jobs with the Clean Energy Corps.

As President, I would support a Clean Energy Financing Authority to support projects to increase efficiency and resiliency upgrades in cities, towns, and rural communities nationwide.

I would prioritize modernizing our electric grid to support localized renewable energy generation, reduced electricity waste, and increased security from sabotage or attack.

And I would increase our investment in basic clean energy research so the U.S. can reclaim the lead on energy innovation, including advancing development, deployment, transmission, and storage for renewable energy and new efficiency technologies.

The fact is, there is no either/or choice between our prosperity and protecting our planet – we can create a future where there are more jobs, and a future with a livable climate. And there is no future for humankind without a livable climate.

The deep-pocketed Democratic donor who has pushed President Obama and Hillary Clinton on environmental issues took advantage of Pope Francis's climate-change encyclical to call on the next president to act on global warming. And he effusively praised Martin O'Malley for taking the lead.

Steyer thanked O'Malley, the long-shot Democratic 2016 contender, for urging the rejection of the Keystone XL pipeline and spelling out a detailed plan of action to confront Earth's rising temperatures. In doing so, Steyer created a clear contrast between O'Malley and Clinton, the Democratic frontrunner who has yet to take a position on the controversial pipeline and so far has not laid out nearly as detailed a vision for fighting global warming.

"Today, Pope Francis issued a powerful and inspirational encyclical on climate change—and I'm happy to see that many of our leaders are already heeding his call to action," Steyer's statement read.

Citing O'Malley's environmental plan, which calls for rejecting Keystone, Steyer added: "This is exactly the type of leadership on climate change the pope, military and business leaders are calling for—and that we need from our next president."

The politics of Steyer's statement are unmistakable. During the 2014 midterm elections, the environmental billionaire spent more than $69 million in a bid to elect Democrats with a strong record on climate. That was enough money to make Steyer that cycle's most generous public donor.