In a sprawling, multimedia report that stresses it is not too late to act, the Biden administration on Tuesday delivered a sobering catalog of climate change’s impacts in every corner of the United States—from battered coasts to parched cornfields to blazing forests. It measures the human toll, including at least 700 people dying of heat-related illness each year, in a nation warming 60 percent more quickly than the world as a whole.
“The effects of human-caused climate change are already far-reaching and worsening across every region of the United States,” the report says. But it adds that each increment of warming avoided through cutting carbon emissions will reduce the risks and harmful impacts.
“While there are still uncertainties about how the planet will react to rapid warming, the degree to which climate change will continue to worsen is largely in human hands,” the report says.
The Fifth National Climate Assessment, or NCA, is a peer-reviewed collaboration by more than 800 scientists from 14 federal agencies, universities and research institutions. It fulfills a mandate Congress put in place in 1990 for regular assessments of the risks of global climate change to the nation, meant to be delivered at least once in every presidential term.
And although the report does not make recommendations and is meant to be policy-neutral, it clearly carries the DNA of President Joe Biden’s administration: It emphasizes solutions being implemented as well as advances still needed. It delves into racial injustice and the jobs benefits of action. And it is packaged and digitally enhanced to deliver the message widely.
The rollout includes an interactive climate atlas, a podcast series, an artwork collection and a poem by U.S. Poet Laureate Ada Limón. Briefings for state and local policymakers will be held, zeroing in on regional impacts.
“Whatever we can do to get this into the hands of people who are making decisions across the country every day,” said Katharine Hayhoe, chief scientist at The Nature Conservancy, professor climate scientist at Texas Tech University and one of the report authors. “That’s what NCA is geared towards, so that we are prepared for and resilient to what the future holds.”
That contrasts sharply with the Fourth NCA, released by President Donald Trump’s administration over Thanksgiving weekend 2018 in an effort—its officials later admitted—to bury its findings.
Hayhoe, widely regarded as one of the nation’s leading science communicators, spoke at a webcast briefing for reporters that the White House organized in advance of the report’s release.
“Too many people still think of climate change as an issue that’s distant from us in space or time or relevance,” she said. “But NCA clearly explains how climate change is affecting us here, in the places where we live, both now and in the future, and across every sector of human and natural society.
“It shows us how if we live in the U.S., the risks matter, and so do our choices,” Hayhoe said.
The new NCA expresses certainty in the science of global warming in line with the assessments of the Intergovernmental Panel on Climate Change: “Human activities—primarily emissions of greenhouse gases from fossil fuel use—have unequivocally caused the global warming observed over the industrial era.”
Focusing on events that have upended life in the United States, the report details how science today has greater confidence in attributing them to climate change than in previous assessments. It says human-induced warming made the record-breaking Pacific Northwest heatwave of June 2021 2 to 4 degrees Fahrenheit hotter than it otherwise would have been, and made Hurricane Harvey’s deluge over Houston in 2017 15 to 20 percent heavier.
With the planet 2 degrees F (1.1 Celsius) warmer than it was in the late 1800s, the report says, “No natural processes known to science could have caused this long-term temperature trend. The only credible explanation for the observed warming is human activities.”
The United States is warming 60 percent more quickly than the global average, since land heats up more quickly than oceans—especially at higher latitudes. Alaska’s temperature has risen 4.2 degrees F ( 2.3 degrees C) since 1970, the report says, “transforming ecosystems, disrupting cultural practices, harming fisheries and other livelihoods, exacerbating health disparities, and placing infrastructure at risk.”