The White House has just released its new National Climate Assessment (NCA), and its central scientific message will be familiar to climate scientists and the White House press corps. Climate impacts are already apparent in the United States, they are likely to worsen, and communities should begin factoring climate change into all kinds of decisions. From Hawaii to Maine, from the fishing industry to manufacturing, the report’s 30 chapters emphasize that “evidence of human-induced climate change continues to strengthen and that impacts are increasing across the country.”

What’s new, however, is that after putting climate issues somewhat on the back burner prior to the 2012 elections, the Obama administration is now giving a full-throated, multiday endorsement to the 1300-page document. Top White House adviser John Podesta and several climate scientists are briefing the press this morning, and President Barack Obama will be sitting down today with TV meteorologists in a series of interviews pegged to the report. This afternoon, visiting "stakeholders" from around the country will gather for a high-profile White House briefing and listening session, the first of a series planned around the country in the coming months.

Today’s assessment is the third official report produced under a 1990 law that instituted the NCA. “Hundreds of the best climate scientists from across the U.S., not just in the public sector but in the private sector as well, have worked over the last 4 years to produce this report,” Podesta told the White House press corps during yesterday’s daily press briefing. “It will contain a huge amount of practical, usable knowledge that state and local decision-makers can take advantage of as they plan on or for the impacts of climate change.”

White House science adviser John Holdren told reporters this morning that the report would "reinforce" all three parts of Obama's 2013 Climate Action Plan: cutting greenhouse gas emissions, adapting to impacts, and leading internationally. Whether that happens, this is by far the fullest embrace of the assessment process in its tumultuous 24-year history. President Bill Clinton had to fight Congress for years to publish the first national assessment, which came out in 2000. A conservative group sued to stop President George W. Bush from publishing a second one. That administration also scrubbed mention of the 2000 report from official documents, angering climate advocates. An environmental group even sued in 2006 to force Bush to publish the report, then 2 years late; it is supposed to be quadrennial. (Here’s a historical blow-by-blow, by a former federal climate office official.) Insiders consider the second official report, published with little fanfare in 2009 during the early days of Obama’s first term, as a “stillborn” effort.

Still, some Washington science policy veterans consider the assessment a rather unique effort for a scientific endeavor, because it includes input from local groups and industries facing possible climate impacts in the future. For instance, scientists and activists involved in the original massive effort that produced the initial 2000 report say the 2014 version also has a strong “bottom-up” flavor. The dozen or so federal agencies that assembled today’s report sponsored some 70 workshops and “listening sessions” over the past 4 years, allowing local groups to not only give input but also shape the report’s form. In addition, small federal grants to state and local nonprofit groups, policymakers, business owners, and academics allowed them to submit formal “input reports” that gave federal officials access to local know-how.

The overall message: “We have enough information on climate to act and we know it’s happening,” says climatologist Victoria Keener, among the recipients of the grants. Keener works for the Honolulu-based East-West Center, a nonprofit. As part of her group’s contribution to the NCA, she led a diverse group in 2012 in publishing a 170-page report called Climate Change and Pacific Islands: Indicators and Impacts. (It’s part of a project called the Pacific Islands Regional Climate Assessment, or PIRCA.) Several of PIRCA’s findings, touching on fishing, sea level rise, disaster planning, and much else, “made it into the final report,” she says. So did one of her document’s anecdotes: It relates how Steve Jacobs, the vice president of a landfill in Waianae, Hawaii, used climate prediction information on La Niña in 2010 to drive a decision to spend $300,000 to upgrade his facility’s storm water system. “When the rain hit we were ready,” he says.

Keener and others are hopeful that the NCA has catalyzed a process that doesn’t stop with the publication of the massive document today. And to keep the buzz going, a federal climate office has created discussion boards, planned follow-on meetings, and organized local organizing committees to follow up on the report with meaningful climate adaptation and resilience planning.

For her part, Keener says that the White House effort has helped drive local regulatory decisions and government interest, including a ruling by a local water board to alter policies in light of predictions of future dry conditions. (See these minutes, page 5.) And Jacobs says he’s expecting more extreme events in the coming years, and has helped lead local efforts to improve planning for hurricanes on the islands. “We believe an ounce of prevention is worth a pound of cure,” he says.

The White House and its hundreds of scientist allies are hoping that kind of thinking makes the NCA the rare report in Washington—one that has a real-world impact.

But some outsiders say the report could have gone further. The World Wildlife Fund's Nicky Sundt, a former federal official with the U.S. Global Change Research Program, lauds the new report as part of "a permanent process" to spin out subsequent updates and reports as the nation prepares for climate change. But he says the federal advisory committee that oversees the report, which includes both government and nongovernment members, prevented the process from including “some of the most important policy issues. … There's nothing in the report on budgets, nothing on national security."