The U.S. National Climate Assessment is mandated by the Global Change Research Act of 1990. The assessment has been conducted about every four years since 2000 and is an authoritative scientific analysis of climate change risks, impacts, and responses in the U.S. The resulting report, mandated by Congress, explains how climate change affects every region of the U.S.
The nation completed its fifth National Climate Assessment (NCA5) in November 2023. The assessment results from an extensive process that includes internal and external review from federal agencies, the public, and external peer review by a panel of experts. The National Oceanic and Atmospheric Administration (NOAA) is the administrative agency for NCA5 and certifies that the report meets the standards required by the Information Quality Act and Evidence Act.
The NCA5 adds further scientific documentation that our planet is warming at an unprecedented rate. Earth’s average surface temperature has risen almost 2F since the late 19th century. Human activity is the principal cause. The science explaining how fossil fuels contribute to climate change has been clear for decades. The NCA5 documents the ways in which the U.S. is experiencing the results of climate change and assesses those risks, challenges, and opportunities. The documented warming affects agriculture, forests, water quality, and the way we live.
The Trump administration is dismantling the government’s ability to monitor a rapidly changing climate. Experienced experts working on the next national assessment were dismissed in April by the Trump administration. The administration also pulled down the federal website that houses national climate assessments and purged the phrase “climate science” from government websites. The president’s proposed budget eliminates funding for weather and climate research. The administration dismisses the threats posed by climate change and is largely disregarding the future impact and economic cost of climate change by their actions.
Steve Ackerman and Jonathan Martin, professors in the UW-Madison department of atmospheric and oceanic sciences, are guests on WHA radio (970 AM) at noon the last Monday of each month. Send them your questions at stevea@ssec.wisc.edu or jemarti1@wisc.edu.