WASHINGTON (dpa-AFX) - For most of the past four decades, observations from the Landsat satellite record show that humans have dominated changes to the U.S. landscape. Recent research revealed a shift in that trend, suggesting that disasters might be catching up.
In a NASA-funded study published in Nature Geoscience, scientists analyzed nearly 35 years of data from NASA/USGS Landsat satellites to better understand what has been shaping the continental U.S. landscape. The researchers, led by former Landsat science team member Zhe Zhu, found that 'human-directed disturbances' like logging, agricultural expansion, and construction have declined, while 'wild disturbances' like wildfires and hurricanes - disasters that can be influenced by human activity but are not controlled by people - have risen in frequency and intensity.
Robert Emberson, associate program manager for the NASA Disasters program and not affiliated with the study, said that understanding the forces transforming the U.S. landscape is critical for future planning. 'If you know what's causing them, you can begin to plan around disasters,' Emberson said. 'Any understanding of causal factors impacts the adaptation strategy.'
This research is especially useful for policymakers working to prepare communities for resilience, he said. For example, a region expecting to see increased wildfires could strategically perform prescribed burns, remove brush or dry grass around homes, and construct new buildings with fire-resilient materials.
Between 1988 and 2022, 18 percent of the land area in the continental U.S. was disturbed at least once, the researchers found. Adding repeated disturbances, the cumulative area disturbed rises to almost 700,000 square miles, equivalent to nearly one-third of the continental U.S. Humans drove more than half of that change, clearing or developing more than 446,000 square miles of land, which is bigger than the size of Texas and California combined. For example, Landsat images from 1985 to 2025, shows the expansion of Reno, Nevada, into a previously undeveloped desert landscape.
Meanwhile, wild disturbances - disasters like wildfires, hurricanes, and landslides-drove much of the remaining change, transforming more than 165,000 square miles of the continental U.S. The Landsat images show areas burned by wildfires in Eldorado National Forest west of California's Lake Tahoe from 1985 to 2025. Major fires in 1992, 2014, and 2022 cleared large swathes of forest, leaving behind bare ground that slowly reforested.
Although human activity has disturbed a larger cumulative area than wild events, the trends over time are moving in opposite directions. That is, land disturbance caused directly by people has been decreasing, while wild disturbance has been increasing.
Specifically, human-directed land disturbances decreased by nearly 232 square miles each year over the course of the study period. Researchers attribute this change to declines in construction, agricultural expansion, and logging, likely brought about by a combination of policy changes, technological improvements, and the 2008 financial crisis's effect on construction.
In contrast, land affected by wild disturbances increased by more than 77 square miles per year. Fire, drought-related stress, and wind disturbances all became more frequent, likely due to climate warming and other environmental factors, the study authors wrote.
Copyright(c) 2026 RTTNews.com. All Rights Reserved
Copyright RTT News/dpa-AFX
© 2026 AFX News
