Alaska Tundra Fires on the Rise

Smokes from East Fork Fire rise from tundra along the Yukon River around St. Mary’s, 6-12-2022. Credit: Jacob Welsh, AK IMT

Five years ago, Adam Young used paleofire evidence to hypothesize how climate warming would affect future tundra fires in Alaska.  Adam basically predicted a big increase in tundra fire occurrence if the average July temperature warmed above a threshold of 13.4°C (56°F:  Young, et al. 2017). This year, Arif Masrur et al. (2022) provided important evidence corroborating Adam’s theory using modern fire and climate records.  The research team use machine learning to determine the relative importance of various climate, prior burn history, and biophysical values on tundra fire occurrence and size. They also tapped the rich collection of field plot data collected by the National Park Service and other management agencies for vegetation characteristics and verification of reburn status.  Arif did, indeed, find a strong increase in recent Alaskan tundra fires concurrent with much warmer summers.  Annual tundra burned area has almost doubled and reburned area has increased by 61% since 2010!  The study also revealed a small but significant feedback effect of previous tundra fires on reburning, validating management strategies like using prescribed fire to reduce wildfire threat near villages.

Figure from Adam Young (2017) showing where he predicted shorter Fire Rotation Periods (more frequent fire) in Alaska with climate warming.

Citations:
Masrur, A., Taylor, A., Harris, L., Barnes, J., and Petrov, A. 2022. Topography, climate and fire history regulate wildfire activity in the Alaskan tundra. Journal of Geophysical Research: Biogeosciences, 127, e2021JG006608. Read the article HERE:  https://doi.org/10.1029/2021JG006608

Young, AM, Higuera PE, Duffy PA and Hu FS. 2017. Climatic thresholds shape northern high-latitude fire regimes and imply vulnerability to future climate change Ecography 40:606–17.  Slides and recording from Adam’s 2019 presentation on this study HERE:  https://www.frames.gov/catalog/60348

Figure 2, Masrur, et al. 2022. [Tundra fire] Regime shift detected in mean annual fire frequency based on AICC fire perimeter data. The detections were performed with the target significance level p = 0.05 and cut-off length l = 20.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s