How do Western US wildfires change over time?

Wildfire frequency drops, but the fires that burn are worse

A new study finds a split trend in the Western United States: wildfires are becoming less frequent, yet the individual fires that do occur are getting larger and more damaging.

Researchers report that from 1992 to 2020, the annual burned area increased by about 4% per year. In 2020, roughly nine million acres burned—described as more than the total land area of the state of Maryland. That figure underscores the scale of recent impacts, even as the number of fire starts declines.

Two takeaways for risk

• Fewer fires: The study indicates wildfire occurrence has fallen over the period examined.
• Bigger fires: The burned-area trend points to increasing fire size and severity when ignition and spread conditions align.

The finding matters for planning and emergency response because it suggests that conventional assumptions—like “fewer fires means overall risk is dropping”—don’t fully hold. A region can experience fewer ignitions but still face intense seasons if fuels, weather, and landscape conditions allow those fires to grow.

This pattern also has downstream consequences. Other reporting in the provided stories notes that burned areas can increase risks such as flooding downstream during subsequent storms by removing vegetation and disrupting hydrologic processes. So, even if fire starts decline, large events can still amplify hazards after the flames are out.

For communities, the practical implication is that preparedness efforts should focus not only on preventing ignitions, but also on limiting fire growth and managing the conditions that let large fires form and spread.