July 15, 2024

The food we eat and the roads we drive on. Our health and safety. Our cultural heritage, natural environments and economic flourishing. Nearly every cherished aspect of American life is under growing threat from climate change and it is effectively too late to prevent many of the harms from worsening over the next decade, a major report from the federal government has concluded.

Global warming caused by human activities — mostly the burning of oil, gas and coal — is raising average temperatures in the United States more quickly than it is across the rest of the planet. The report issued Tuesday, the National Climate Assessment, is the government’s premier compilation of scientific knowledge on what this means for the country and how Americans are responding.

“Too many people still think of climate change as an issue that’s distant from us in space or time or relevance,” said Katharine Hayhoe, an atmospheric scientist at Texas Tech University who contributed to the report. The new assessment, the fifth of its kind, shows “how climate change is affecting us here, in the places where we live, both now and in the future,” she said.

Human-driven warming is intensifying wildfires in the West, droughts in the Great Plains and heat waves coast to coast. It is causing hurricanes to strengthen more quickly in the Atlantic and loading storms of all kinds with more rain. So far this year, the nation has experienced a record 25 billion-dollar weather disasters, many of them exacerbated by the hotter climate.

Yet not all is lost, according to the report. Cost-effective tools and technologies to significantly reduce America’s contribution to global warming already exist, the report finds. U.S. emissions of heat-trapping gases fell by 12 percent between 2005 and 2019 as the country has shifted from coal toward natural gas and renewable sources. And options are increasing for electrifying energy use, reducing energy demand and protecting natural carbon sinks like forests and wetlands, the report says.

Even so, the United States and other industrialized countries are still curbing their emissions so sluggishly that a certain amount of additional greenhouse warming is essentially locked in, forcing societies to learn to live with the effects. On this front, the report concludes that Americans’ efforts have mostly been “incremental” instead of “transformative”: installing air-conditioners rather than redesigning buildings, increasing irrigation rather than reimagining how and where crops are grown, elevating homes rather than directing new development away from floodplains.

Americans, the report says, need to make deeper changes to the ways they work, manage their environments and move through them to become resilient to the climate conditions that humanity’s past choices have brought about, conditions that Earth has never before experienced while hosting so many members of our species.

More than 750 experts evaluated thousands of academic studies and other types of knowledge to compile the latest National Climate Assessment, which is being issued as world leaders prepare to gather in the United Arab Emirates for annual United Nations climate talks at the end of this month.

Federal agencies have produced new assessments twice a decade or so since 2000, as mandated by a 1990 law. After the previous installment was issued in 2018, the Trump administration tried but largely failed to thwart work on the latest one.

The new report is also coming out as President Biden begins his push for re-election. Many young voters who are alarmed by global warming have expressed disapproval of Mr. Biden’s decision to greenlight new oil drilling in Alaska. Biden administration officials said the assessment’s findings showed how the president’s policies were moving the nation toward a clean-energy future.

With the report’s release, Mr. Biden was also expected to announce on Tuesday $6 billion in investments to modernize America’s electric grids and support projects that address the unequal effects of environmental hazards on minority and tribal communities.

“We’ve got climate solutions that can be made in America and are being made in America, that we’re deploying brick by brick and block by block,” said Ali Zaidi, the White House national climate adviser. “That gives us hope.”

Every part of the country is feeling the effects of the warming planet, the report finds. Rising fatalities from extreme heat in the Southwest. Earlier and longer pollen seasons in Texas. Northward expansion of crop pests in the Corn Belt. More damaging hailstorms in Wyoming and Nebraska. Stronger hurricanes in Puerto Rico and the Virgin Islands. Shifting ranges for disease-spreading ticks and mosquitoes in many regions.

The latest climate assessment is the first to include a dedicated chapter on economics, reflecting scholars’ growing interest in pinning down both the direct costs of climate change and its wider effects on households, businesses and markets, said Solomon M. Hsiang, a professor of public policy at the University of California, Berkeley, who helped lead the writing of the chapter.

These effects vary between regions, with hotter ones facing more harm and colder ones potentially benefiting. But the report cites studies showing an overall loss in the nation’s economic well-being. For every 1 degree Fahrenheit that the planet warms, the U.S. economy’s growth each year is 0.13 percentage points slower than it would be otherwise, the report finds, a seemingly small effect that can add up, over decades, to a sizable amount of forgone prosperity.

Such metrics do not, however, capture the full effects of warming on less-tangible things Americans value, including human health, ecosystems, trades like fishing that are passed down over generations and even recreational activities such as skiing, camping and other outdoor pastimes that wildfire smoke and scorching heat increasingly lace with peril. “Nonmarket effects of climate change in many cases are some of the largest,” Dr. Hsiang said.

Governments do much of the spending to respond and adapt to climate change, and the assessment warns of increased costs of public programs such as disaster aid, wildfire suppression, crop insurance subsidies, endangered species protection and health care. Such expenditures could rise even as climate change undercuts tax revenues by reducing incomes and housing values, the report says. Private insurers are already so tired of losing money in catastrophe-prone places like California that they are restricting coverage or pulling out.

The assessment finds that efforts to plan for climate threats have expanded in recent years. Around two in five states and 90 percent of U.S.-based companies have assessed their climate risks. Eighteen states have climate adaptation plans; another six are working on theirs.

So far, though, implementation has been “insufficient,” the report concludes. Funding is a challenge, it says, but so is coordination.

The assessment cites a few programs in California and Florida that have tried to plan for climate adaptation across city and county lines. Yet when not properly designed and monitored, adaptation efforts can lead to unintended side effects, said Katharine J. Mach, an environmental scientist at the University of Miami who contributed to the report. “In some cases, we may be working well on climate but creating other issues,” she said.

Disaster relief, for example, goes disproportionately to cities and towns, which could be exacerbating urban-rural disparities, Dr. Mach said. Federal buyouts of homes in vulnerable places have occurred disproportionately in wealthy counties, largely because agencies there can better navigate the bureaucratic requirements.

The assessment acknowledges America’s progress toward pumping less carbon into the atmosphere but says the country must do more — and much, much faster. Emissions from generating electricity in the United States are down about 40 percent from 2005. Yet emissions from transportation rose by nearly 25 percent between 1990 and 2018, even as vehicles became more energy efficient. The reason? Americans are driving more.

Achieving the nation’s emissions goals will probably require continued advancement in technologies like hydrogen fuel and carbon dioxide removal, the report says. But it will also involve doing more of the things we can do already, such as generating electricity with clean sources and replacing car engines, furnaces and boilers with electric versions.

“People sometimes focus so much on the stuff that we don’t know how to do that it paralyzes them in thinking about the options that we have today,” said Steven J. Davis, a professor of earth systems science at the University of California, Irvine, and another author of the report.

Still, solar and wind facilities will require enormous amounts of land, potentially 3 to 13 percent of the area of the contiguous United States, the report finds. Around 8 million Americans, or 5 percent of the labor force, work in energy-related jobs, many of which are at risk in the shift to renewable sources. The Biden administration’s plans for offshore wind power have run into trouble as rising interest rates, supply chain delays and local opposition stymie projects.

Dr. Davis expressed optimism that the hurdles could be navigated. The assessment cites analyses showing that clean energy and related industries can create enough jobs to offset declines in fossil-fuel employment. Switching to zero-carbon energy could reduce air pollution enough to prevent 200,000 to 2 million deaths by 2050, the report says.

“It’s not all bad trade-offs,” Dr. Davis said.

Leave a Reply

Your email address will not be published. Required fields are marked *