The impacts of climate change threaten “the things Americans value most,” according to the latest version of the federal interagency National Climate Assessment (NCA).
The latest NCA, the first since 2018, warns that “more intense extreme events and long-term climate changes make it harder to maintain safe homes and healthy families, reliable public services, a sustainable economy, thriving ecosystems, and strong communities.”
The report adds that many of those extreme impacts are already reality and poised to worsen in parts of the country. For example, parts of the country have seen intensified rainfall and flooding in regions like the Northeast and the Midwest, according to the NCA. These phenomena have consequences beyond immediate damages, the report notes — they can also result in runoff that damages crops and water supplies.
For example, between 1981 and 2016, excess precipitation cost the U.S. about as much in maize crop yields as extreme drought would have.
Droughts, meanwhile, have caused nearly $300 billion in damages over the last four decades, and their impact is likely to intensify in the future, particularly in the Southwest, which has already seen a drought lasting most of this century.
Another emerging threat is that of so-called compound events, or multiple extreme weather events that hit a single area consecutively or concurrently. These events strain local supply chains and emergency services, as well as causing side effects like mass die-offs of wildlife that can be a major local food source.
One such example is the record temperatures in California and the Pacific Northwest in 2020, which led to a particularly destructive fire season across the region. The regional drought extended into the next year and, combined with another heat wave and worse-than-average snow season, caused more than $36 billion in damages, according to the report.
The impact of climate change also exacerbates, and will exacerbate, existing social inequalities. Historical discrimination patterns mean minority neighborhoods are more likely to be in low-lying, flood-prone areas and those vulnerable to industrial pollution. They also have fewer trees and more pavement, creating so-called heat islands that make them more susceptible to extreme heat — in some cases, up to 12.6 degrees Fahrenheit than richer, whiter neighborhoods during heatwaves.
The latest NCA comes during the COP27 United Nations climate summit in Egypt, where global inequalities around the impact of climate change is a major theme as well. International “loss and damages” funding for those nations facing its worst impacts made the conference agenda for the first time this year.