A new study explores the link between man-made climate change and the risk of forest fires. | Monterey County NOW Introduction

Christopher Neely here, thankful for the rain part of the county lived last night until this morning, and my fingers crossed that we can get through the end of the year without news of a local wildfire.

Unfortunately, sometimes it feels like this is what it happened to– fingers crossed, hoping that human superstition can outweigh the increased fire risks created by man-made warming. Of course, we can do more to control fires once they are started, such as clearing and managing our forests. But in terms of our ability to minimize wildfire weather, this ship has sailed for now and any impact we can muster in the future is unlikely to be noticeable for years, if at all.

The relationship between man-made climate change and the increased risk of forest fires has been reported ad nauseam. However, a new study by UCLA researchers clarifies the impact of modern society on wildfire conditions with real numbers. In the study published today in the journal Proceedings of the National Academy of Sciences, researchers use observational analyzes and existing climate models to track the human impact on vapor pressure deficit (essentially: the difference between how much moisture the air can carry and how much it carries actually) over the past few decades, a measure they cited as the “primary meteorological variable that controls forest fires” and a “robust and physically meaningful indicator of forest fire risk”. While this is not the only variable that contributes to the risk of forest fires, the impact is clear: the greater the vapor pressure deficit, the greater the risk of forest fires.

Human-induced warming is responsible for 68-88% of the increase in vapor pressure deficit trend observed in the western United States between 1979 and 2020, according to the researchers. Observational analysis used by researchers in the study showed that natural causes were responsible for about 32% of the increase in vapor pressure deficit during this period, leaving 68% “likely due to anthropogenic warming.” “. Existing climate models have shown humans to be responsible for about 88 percent of the vapor pressure deficit trend, leading the researchers to derive a range for human impact.

“Our results suggest that the [western U.S.] seems to have crossed a critical threshold and that the dominant control over the variation of the fire time in the [western U.S.] has gone from natural climate variability to forced anthropogenic warming, ”the study concludes. “The trend of increasing risk is likely to continue over the course of the [western U.S.] … This change in risk requires urgent and effective societal responses to adapt and mitigate.

A more accessible statistic, although not easier to swallow, is the total number of acres burned in the western United States during the same time period. According to the study, between 1984 and 2000, 1.69 million acres burned in the region, up from 3.35 million acres between 2001 and 2018. Both are pale compared to 8.8 million acres. burned in 2020 only.

What will “urgent and effective societal adaptation and mitigation responses” look like? California and the rest of the west are figuring this out. In this week’s print edition of Weekly (which will be on newsstands Thursday), I write about a controlled burn experiment that took place on the Santa Lucia Reservation in Carmel Valley – an ancient land management and fire control tactic that modern society has embraced. distant. It can take many forms of ancient wisdom and environmental awareness to deal with our current reality. Government leadership would also be helpful. Fingers crossed that COP26 is more than a speech this year.