The following blog post by Trip Van Noppen originally ran on the Huffington Post on October 8, 2013.

The most damning and decisive report yet on humankind’s contribution to climate change was delivered by the United Nations Intergovernmental Panel on Climate Change little more than a week ago. The report, the most precise yet thanks to advances in scientific monitoring, confirms that climate change impacts are outpacing previous projections for ocean warming, the rate of glacial ice melt in the arctic, and sea level rise. But the biggest takeaway of the report is the unprecedented step it takes in setting a carbon budget.

Previously, scientists had been reluctant to put a number on the upper limit of tons of carbon pollution we could put in the atmosphere and still avoid the worst that will come with a temperature rise of more than 2°F. The IPCC now agrees that 1 trillion metric tons is the absolute maximum amount of carbon pollution that the planet can withstand without intolerable consequences.

We’ve already spent down over half of our carbon emissions budget in the last 250 years, and with our current spending habits, we’re on course to blow through the rest in the next 25. We have enough experience already with the devastating human and economic costs of climate change to know that we have to start living within our carbon means. We cannot blow this carbon budget if we want to carry on living in a hospitable world.

The estimated fossil fuel reserves still in the ground represent more than 3 trillion tons of carbon emissions. Instead of leading the global solution on climate change and seizing the most compelling economic opportunity of our time: clean energy technology. U.S. politicians on both sides of the aisle are intent on developing every available fossil fuel reserve, setting us on an even faster course to disaster.

The drive to drill and mine anywhere, by whatever extreme means, is a disastrous substitute for a coherent American energy policy. If we drill the remaining oil in the Arctic, allow fracking of oil and gas around the country, blow the tops of mountains to get at the last of our Appalachian coal, and set out to mine all of the coal in Alaska and the Powder River Basin of Montana and Wyoming, we will have no hope of avoiding catastrophic climate change. Based on World Bank estimates, the fossil fuel infrastructure already built will consume the remaining carbon budget, so we should not build even more projects, like tar sands pipelines and liquefied natural gas (LNG) export facilities.

Glaciers, permafrost, and icecaps are melting rapidly. (Lee Prince / Shutterstock)

We only have to look at the Arctic to understand why a radical shift in energy policy is critical. The Arctic is warming more than twice as fast as the global average, and it affects all of us. Scientists at this very moment are observing glaciers melting several times faster than before and sea levels rising dangerously fast, contributing to sea level rise and increased extreme weather around the world. The IPCC projects sea-level rise of 5–6 feet by 2100. This would be devastating to coastal communities around the world, including in the United States in the coming decades as storm surges reach further inland and waters rise. A recent study estimates that average annual losses from flooding in the world’s biggest coastal cities—including New York City, Miami, New Orleans, Boston, and Tampa Bay—could rise to $1 trillion per year by 2050. These cities now spend about $6 billion per year combined on flood losses.

Many state and local officials, especially in New York and New Jersey, understand the true costs of climate change, as they have been forced to contend with extreme storms, droughts, and wildfires. They are right now dealing with the pressing need for action at every level of government.

The president’s climate action plan is the federal start button, and its test will be the administration’s willingness to finalize strong standards to limit carbon pollution from new and existing power plants. In the meantime, every state in the country has the power to force our power companies to invest in energy efficiency programs, renewable energy, and smart grid technologies that will power us more safely, and also more cheaply, into the next century.

Citizens are also realizing they can force these changes. We at Earthjustice have joined with community groups from Arctic Alaska to the mountains of Appalachia to stop the extraction of dirty and dangerous fossil fuels. Communities are taking challenges against corporate fossil fuel giants to their last line of defense, the courts, and the people are winning. In Indiana, Ohio, and Kentucky, communities came out on top in a lawsuit that will shut down three of the nation’s worst-actor coal plants and invest in wind and solar. The town of Dryden, New York, is defending its right to keep fracking out of its borders and waters, and so far, it’s winning. In Kansas, communities are now celebrating a hard-fought victory to block a dirty coal plant that would have set their state back. In Hawaiʻi, community and legal pressure has forced regulators and utilities to introduce path-breaking plans to enable a massive expansion of rooftop solar systems connected to the grid. These are the kinds of battles every community and state in the nation must be braced to fight if we are to live within our carbon budget.

Coal-fired power plants are major producers of carbon pollution. (Calin Tatu / Shutterstock)

While deep cuts in carbon pollution are the backbone of our long-term climate strategy, there are other atmospheric pollutants that we can reduce now for quick climate benefit in the coming decades. Black carbon, the soot emitted from diesel engines, agricultural burning and other sources, is the second most powerful climate pollutant after carbon dioxide. And in the Arctic, soot is an even more powerful climate pollutant because it warms both in the air as it absorbs sunlight and then again when it deposits on snow and ice, accelerating melting. We already have the technology to cut soot pollution—a bipartisan Senate subcommittee hearing last month supported black carbon reductions—but we need tighter standards on diesel emissions and agricultural burning.

Now is the time for the United States to lead in tackling climate change. In order to preserve our economy and our communities, we must push for bipartisan change at every level, as well as a fundamental culture change that embraces climate solutions and clean energy technologies.