Another season of extreme weather events is upon us. A severe storm, with winds up to 70 miles per hour, whipped its way from Illinois to Washington, D.C. Meanwhile, Colorado is experiencing one of its worst wildfires in history—the Black Forest Fire has burned 15,700 acres, displaced more than 38,000 people, and impacted 13,000 homes. These events are reminders of what the world will look like as our climate system moves into increasingly dangerous and unfamiliar territory.

This week also brought a trifecta of events with significant implications for climate change.

The latest report from the International Energy Agency revealed that energy-related carbon dioxide emissions hit an all-time high in 2012. These emissions are driving up global temperatures and increasing climate instability. The IEA concludes that it’s not too late to change course, but the window for action is closing rapidly.

Our current response to climate change is grossly inadequate. Fortunately, there are some signs that the winds are starting to change. For instance, this week Mayor Michael Bloomberg presented a bold plan to protect New York City from sea level rise, storm surge, and other climate-related impacts. Mayor Bloomberg proposed $20 billion in investments that would enhance infrastructure to prevent flooding, increase the resilience of power systems, strengthen the public health system, and more. These are the types of investments that cities—and nations—need to build climate resilience.

Other cities have much to learn from New York’s approach. Under PlaNYC, the city has set an ambitious target to reduce its carbon emissions by 30 percent by 2020 (and is more than halfway there), and it is now preparing its citizens climate impacts. Not all cities can afford to make the level of investment as New York, and many developing nations will need support to do so.

The good news is that reducing emissions can be done affordably. Further, it’s clear that taking action now can prevent greater costs later on. The IEA’s report, for instance, offers four commonsense recommendations that rely on existing technologies and carry no net economic cost.

Meanwhile, the costs of climate change are becoming more and more apparent. According to the National Climatic Data Center, in 2012, there were 11 events that cost more than $1 billion each, with a cumulative total of more than $110 billion. Hurricane Sandy cost at least $60 billion to U.S. taxpayers. The U.S. drought, from 2012 to 2013, could cost more than $200 billion, according to some recent estimates.

In another sign of progress, at the U.S.-China summit last week, President Obama and President Xi agreed to work together to phase down hydrofluorocarbons (HFCs), a potent greenhouse gas commonly used in refrigerators and air conditioners. Cutting HFCs could bring the equivalent of eliminating two years of greenhouse gases.

This announcement also put a renewed spotlight on climate change, while reinforcing the fact that it’s an area where the U.S. and China can find common ground.

The Obama Administration, of course, has the power to take additional action to reduce U.S. emissions. The steps it can take are clear. WRI analysis has identified four actions that would enable the U.S. to reach its goal of reducing emissions 17 percent below 2005 levels by 2020. These include: reducing carbon emissions from power plants; cutting HFCs (internationally and through the Clean Air Act); limiting methane leaks from natural gas systems; and increasing energy efficiency. All of these fall within the president’s executive authority.

These are not the only possible actions, but together they could form the basis of a national plan that would protect communities and businesses at home, while enhancing trust overseas.

There are rumblings that President Obama is preparing to step up the U.S. response. White House energy advisor, Heather Zichal, told reporters, “In the coming weeks and months, you can expect to hear more from the president on this issue, as well as on the agenda.”

This would be a most welcome development. Climate impacts are here. The case for action is clear. By building on this week’s signs of progress, the U.S. Administration—and other national leaders—can chart a new and safer course on this global challenge.