The cascading effects of climate change promise to devastate Americans’ health and safety, quality of life, and economic opportunities unless drastic measures are taken in the immediate future, a new government report backed by 13 federal agencies warns.
Volume Two of the Fourth National Climate Assessment, a quadrennial, congressionally mandated report, draws on decades’ worth of research compiled by more than 300 scientists to chart predicted impacts of global warming—as well as the increasingly ubiquitous signs of climate change already evident across the United States. The gist of the report, according to Robinson Meyer of The Atlantic, is an all-too-familiar call to action: “Climate change is happening now, and humans are causing it.”
But as Coral Davenport and Kendra Pierre-Louis report for The New York Times, the 1,656-page assessment offers an array of new insights, too. Projected effects outlined in the last climate assessment, published in 2014, have materialized in the form of increased coastal flooding, crop failures and brutal wildfire seasons. And, if the country fails to take decisive action, these scenarios promise to multiply, triggering an economic crisis twice as damaging as the Great Recession by the end of the 21st century. Volume Two even places a price tag on these effects, projecting costs of $141 billion from heat-related deaths, $118 billion from sea level rise and $32 billion from infrastructure damage by 2100.
To provide a better sense of local-scale impacts, the report traces climate change’s current and anticipated effects on different regions of the country. Brady Dennis and Chris Mooney of The Washington Post highlight several examples already seen across the U.S., including severe coral reef bleaching in the Caribbean, Hawaii and Florida; staggering warming in the sole Arctic state of Alaska; and threatened water supplies linked with decreased snow retention in western mountain ranges.
Looking toward the future, Davenport and Pierre-Louis write that wildfires similar to those recently seen in California could bombard Southeastern states such as Tennessee and Georgia, which Andrew Light, a report co-author and senior fellow at the World Resources Institute, describes as having “no experience with an annual dangerous fire season, or at least very little.” Further north, Meyer notes, oceanfront barrier islands situated in New England and the mid-Atlantic could erode and narrow, while to the west, crop yields could shrink dramatically. Sea-level rise along U.S. coasts could reach between roughly three to five feet.
According to Brad Plumer and Henry Fountain of The New York Times, the report emphasizes climate change’s intersecting impacts on various economic sectors, including trade and agriculture. In California, for example, drought and population changes have affected demand for water and energy; in New York, 2012's Superstorm Sandy triggered flooding in subway and highway tunnels, making it difficult for workers to repair the state’s electrical systems.
Some effects, particularly those linked with health and social or economic inequality, are projected to have an adverse effect on individuals across the country, not just those living in specific areas. As Jen Christensen and Michael Nedelman write for CNN, rising temperatures will lead to an increase in mosquito- and tick-borne diseases, including Zika, dengue and West Nile. Asthma and allergies will worsen. At-risk communities already disadvantaged by social or economic status will face much higher risks of illness and death.
In conjunction with an October report released by the United Nation’s Intergovernmental Panel on Climate Change, the new assessment paints a sobering portrait of the world’s future. But there’s still time to counter the worst effects of global warming. Vox’s Umair Irfan explains that aggressively curbing carbon dioxide emissions to limit the rise in global temperature is a key step forward, as is shifting to cleaner energy. Even though a certain degree of warming is unavoidable, the report states that “adaptation and mitigation policies” can help communities deal with higher temperatures, rising sea levels and extreme weather.
It remains to be seen whether the notoriously climate change-skeptical Trump administration will heed the report’s advice, but as Katharine Hayhoe, a co-author and atmospheric scientist at Texas Tech University, tells The Atlantic’s Meyer, “This isn’t information that’s only for the federal government. This is information that every city needs, every state needs, increasingly every business needs, and every homeowner needs. This is information that every human needs.”
She concludes, “It’s not that we care about a 1-degree increase in global temperature in the abstract. We care about water, we care about food, we care about the economy—and every single one of those things is being affected by climate change today.”