Tag Archives: fire regimes

Jan 6 2023

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.
Jun 15 2016

Adam Young consults the crystal ball on future fire regime across Alaska

A paper just published by the indefatigable Adam Young, a PhD candidate at the University of Idaho, and colleagues pulls together a lot of information about climate, forest, tundra and fire to offer a glimpse of potential future fire regimes in different parts of Alaska.  By looking at fire occurrence at a multi-decadal time scale, the researchers drill down into how fire rotations are likely to respond to climate projections at a regional scale.

Young Fig 6 exerpt

Exerpt from Fig. 6, Young et al. 2016. Figures in the paper not only show the observed fire rotation for 19 subregions of Alaska (Figure A2 in supplement) with 60 years of fire occurrence data, but also project future rotations under various climate scenarios (in this case a mean of of 5 global climate models).

The use of advanced statistical models to build fire-landscape response models for boreal forest and tundra reaffirms prior findings of the sensitivity of fire regime to summer temperatures and moisture deficit. However, the effect is not uniform among regions: they identify a threshold at about 56⁰ F (30-yr mean temperature of the warmest month) and another threshold for annual precipitation where fire occurrence really seems to jump.  This latter finding accounts for results which project large increases in 30-year probability of burning for areas where these thresholds will be crossed in the next several decades.  For example, models project the Brooks Range foothills of the North Slope, Noatak tundra and the Y-K Delta may see increases in fire 4-20x greater than historical levels.  Some tundra areas are likely to experience fire frequency increase to levels not observed in the paleo record, spanning the past 6,000-35,000 years.  Across most of the boreal forest, fire rotation periods are projected to be less than 100 years by end of the 21st century.  This is useful information for natural resources management as well as fire protection agencies—a concise, well-researched, well-illustrated paper—put it on your summer reading list.

Young, A. M., Higuera, P. E., Duffy, P. A. and Hu, F. S. (2016), Climatic thresholds shape northern high-latitude fire regimes and imply vulnerability to future climate change. Ecography 39: 1-12. http://dx.doi.org/10.1111/ecog.02205

Feb 12 2016

Fire and Carbon Stores: the Rest of the Story

Estimates of carbon released from combustion of vegetation and organic soil during wildfires have improved dramatically over the past decade.  Biomass inventory, fire effects and fire severity studies have contributed more accurate data to improve these models. (See Ottmar 2007, Brendan Rogers webinar 2015)  However, figuring out the net effect of all the various effects of fire, the recovery phase and warming climate on the carbon stored in Alaska’s forests and tundra is a lot more challenging!  You’d have to consider changes in burn extent and/or severity, increases in plant productivity in recovering burns, changes in species composition and what that means for productivity, changes in permafCaptureIEMrost distribution and soil C decomposition, methane emissions and carbon fluxes in lake systems and wetlands–etc.!  A team lead by Dr. Dave McGuire at UAF has taken on this modeling challenge by applying their Integrated Ecosystem Model (IEM) which includes modules for fire, permafrost, and carbon cycling. Dave recently presented an overview of their findings at an IARPC-WCT/AFSC joint webinar (available HERE).  In a nutshell, they found: 1) tundra holds 2x the carbon that boreal forest does in the same area 2) there has been a net C loss from boreal land area of about 8 Tg/yr over the last 60 years, primarily driven by large fires during the 2000’s 3) arctic tundra and SE Alaska still act as C sinks, compensating for these losses so that overall, Alaska sequesters about 3.7 Tg/yr,  4) increases in fire extent predicted with with warming climate will release even more C, but longer growing seasons and increased plant growth (as much as 8-19% increased productivity throughoCaptureALFut the remainder of this century) with warmer climate and higher CO2 concentration in the atmosphere are estimated to offset these losses under most of the climate projection scenarios. Since this nutshell summary glosses over a lot, you should take a look at the presentation and the SNAP projects page with information on scenarios and the individual models used.

Apr 4 2014

April 8th Science for Lunch: Shortened Fire Return Intervals in Alaska


Jennifer Barnes, NPS Regional Fire Ecologist

Tuesday April 8th, 12:00 pm AK time. Contact NPS Stacia Backensto for information:  907-455-0669.

The Uluksian fire of 2007 (by P. Higuera).

The Uluksian fire of 2007 (by P. Higuera).

Jennifer will discuss the results of recent NPS studies on climate change impacts to boreal forest and tundra fire regimes.

Find the recording <HERE>.

Apr 30 2012

Tundra burning in Alaska: Rare events or harbinger of climate change? Join the Webinar!

The 2007 Uluksian Fire (photo courtesy of P. Higuera).

Dr. Philip Higuera (assistant professor at the College of Natural Resources, University of Idaho) will be joining us for a webinar on May 24, 2012 (1:00-2:00 pm AKDT) entitled “Tundra burning in Alaska: Rare event of harbinger of climate change?”.  Philip’s current research is focused on how climate, vegetation, and human activities interact with fire occurrence and fire regimes (from across years to across millenia).  He is also the Director of the Paleoecology and Fire Ecology Lab  where students and researchers work on charcoal and pollen analysis in lake-sediment records,  dendrochronology, and spatially-explicit modeling and analyses for areas in the US Rocky Mountains, Alaska, and abroad in Tasmania, Australia.

Link to recording <HERE>

Webinar at a Glance:

Dr. Philip Higuera will be presenting results from past and ongoing research focused on understanding the causes and consequences of tundra burning in the past, present, and future. The talk will integrate several lines of work, including reconstructing tundra fire history in the recent and distant past (2000-14,000 yr), quantifying relationships among modern climate, vegetation, and tundra burning, and anticipating future tundra burning given future climate scenarios.

Continue reading →

Feb 28 2012

More Catastrophic Fires Ahead for Western U.S.

News from Science Daily:

More Catastrophic Fires Ahead for Western U.S..

Read the Full Journal Article:

J. R. Marlon, P. J. Bartlein, D. G. Gavin, C. J. Long, R. S. Anderson, C. E. Briles, K. J. Brown, D. Colombaroli, D. J. Hallett, M. J. Power, E. A. Scharf, M. K. Walsh. PNAS Plus: Long-term perspective on wildfires in the western USA. Proceedings of the National Academy of Sciences, 2012; DOI: 10.1073/pnas.1112839109

Direct from the Source:

Inside NAU (Northern Arizona University)

Feb 28 2012

Once Burned, Twice Shy: Webinar Wrap Up

Here’s a big Thank You to everyone who attended last week’s webinar “Once burned, twice shy”, presented on Feb. 23rd.  For those who could not attend or who have been eagerly awaiting the follow up materials, please feel free to  explore the videos, documents and links below.  (For more information, see our previous post on this webinar.)

In Summary

This slideshow requires JavaScript.

(Slides by Dr. Carissa Brown.)

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Feb 9 2012

Once burned, twice shy: Repeat fires result in black spruce regeneration failure (Webinar)

A re-burned fire with little to no black spruce regeneration, 2007. Photo courtesy of C. Brown.

Dr. Carissa Brown, Postdoctoral Researcher at the University of Sherbrooke, will be joining us for a webinar on February 23, 2012 (11:00 am to noon AKST) entitled “Once burned, twice shy: Repeat fires result in black spruce regeneration failure.”  Dr. Brown is currently studying plant species and communities at the edge of their range, focusing on the direct and indirect effects of climate change on species distribution at northern latitudes. Most recently, her work has focused on the responses to altered fire frequency at the northern margin of the boreal forest, particularly in black spruce forests.

Link to recording <HERE>

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Dec 21 2011

Rapid rise in wildfires in large parts of Canada? Ecologists find threshold values for natural wildfires

Photo from Science Daily, Credit Evgney Dubinchuk/Fotolia

"A rapid rise in wildfires has been predicted for a large part of Canada" (Credit:Evgeny Dubinchuk/Fotolia) (Photo from Science Daily)

News from Science Daily:

Rapid rise in wildfires in large parts of Canada? Ecologists find threshold values for natural wildfires.

Read the Journal Article behind this summary:

1. Richard D. Zinck, Mercedes Pascual, Volker Grimm. Understanding Shifts in Wildfire Regimes as Emergent Threshold Phenomena. The American Naturalist, 2011; 178 (6): E149 DOI: 10.1086/662675

Dec 14 2011

November 2011 Fire Science Publications

Can’t seem to stay up to date?  Let us do some of the work. 

We’ve put together a bibliography of November’s (plus or minus a few weeks) new fire science publications related to Alaska and the boreal forest.  Download a simple bibliography or an annotated version, both in a pdf format including URLs for each reference.  Just want the highlights? We showcased a few of our “Top Picks” below. 

November 2011 Fire Publications – Bibliography (pdf)

November 2011 Fire Publications – Annotated Bibliography (pdf)

Our “Top Picks”

Werth, Paul A.; Potter, Brian E.; Clements, Craig B.; Finney, Mark A.; Goodrick, Scott L.; Alexander, Martin E.; Cruz, Miguel G.; Forthofer, Jason A.; McAllister, Sara S. 2011. Synthesis of knowledge of extreme fire behavior: volume I for fire managers. Gen. Tech. Rep. PNW-GTR-854. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 144 p.

 

 

 

 

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