Tag Archives: Alaska

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.
Dec 5 2022

Western Forester Articles on Alaska!

See also p. 24 WFOctNovDec2022 for updates on fuel break projects on the Kenai by Tracy Robillard.

Please also note a great Post-Doc opportunity with one of AFSC’s collaborating scientists to study boreal climate change impacts and mitigation methods. It pays well (~$68,000 year for two years) and comes with a lot of flexibility and opportunities for global scale collaboration. The ad is here: https://www.edf.org/jobs/cooley-postdoctoral-science-fellow

Mar 6 2022

The Face of a Scientist

The face of a scientist: does that conjure an image of a certain gender, race, and age?  Albert Einstein perhaps?  Those stereotypes are changing:  meet Dr. Yaping Chen–a rising star of science with a spectacular track record.  The last 3 years she has come up with one mind-boggling revelation after another about how fire works in the Alaska tundra.  After a MS degree in environmental engineering in China, Dr. Chen completed her PhD in the lab of the venerable Dr. Feng Sheng Hu at the University of Illinois.  I first met her presenting a poster on the Nimrod Hill fire (Imuruk Lake, on the Seward Peninsula) at an American Geophysical Union meeting in 2019.  The work was novel, ingenious, and suggestive of new ways to study fires with new computational and remote sensing tools. That was just the tip of the iceberg–or the thermokarst, if you will! Since then Dr. Chen has published numerous diverse research studies improving our understanding of dueling post-fire successional trajectories in tundra, improved burn severity mapping of legacy tundra fires, and fire regime effects on carbon balance.  Her most recent paper outlines the role of tundra fire vs. climate warming in thawing permafrost in Alaska tundra statewide!  If you’ve missed any of these important papers for your collection, links are included below.  Now Dr. Chen is a post-doctoral researcher at the Virginia Institute of Marine Science, continuing her work on unraveling impacts of climate change.  Thank you, Dr. Chen for all you’ve revealed to us in Alaska!

Fire hastens permafrost collapse in Arctic tundra: Short AAAS summary of Chen’s most recent paper>>>

Below: Graphical Abstract from Chen, et al. 2021 One Earth publication, illustrating the increase in thermokarst rates across arctic Alaska, and highlighting impact of fire in hastening thaw.

Jan 7 2022

Everything you wanted to know about fire behavior analysis in Alaska

In one handy paper that came out in 2021, Alaska fire analysts Robert “Zeke” Ziel and Chris Moore have compiled how-to’s, resources, fuel model-to-vegetation type crosswalks, and pro tips and secrets. The reference takes you all the way from introduction to the Canadian Forest Fire Danger Rating system to how to conduct an analysis of fire behavior in WFDSS (Wildfire Decision Support System used by fire agencies). Included are such perplexing topics as how to estimate live and dead fuel moisture, what are the available short-term and near-term fire models, what do do about winds, which National fuel models require “tweaking” in Alaska, and sources of vegetation map products and satellite imagery. Fire behavior analysts definitely want to review this before the fire season and make sure it’s handy in their kit if they plan to work in Alaska, and researchers will also find this an extremely useful state-of-the-art comprehensive review of how fire behavior analysis currently works in practice.

Moore, Chris; Ziel, Robert. 2021. Fire Analysis in Alaska: A Quick Reference. Unpublished report. Alaska Wildland Fire Coordinating Group. 47 p.

From the authors: “Alaska is faced with a unique fire management problem that has been handled in an interagency way for more than 30 years. The evolution of fire management has led to a different approach in interagency cooperation; weather data management; fire behavior and fire danger implementation; GIS management; and overall fire suppression strategies. This guide is intended to provide standardized inputs for initial analysis; these are not hard and fast rules to be strictly followed throughout an incident.”

Monitoring winds during a prescribed fire.
Oct 25 2021

Fuel Treatment Preferences of Alaskan Homeowners

A new study just published in Sustainability surveyed Fairbanks Northstar Borough and Kenai Peninsula Borough homeowners about their willingness to pay for types of fuelbreaks on their property, their neighbor’s property and how public land treatments nearby affected their choices. Molina et al. found that surveyed homeowners (n=358) had a greater willingness-to-pay for fire hazard reduction when a moderate number of neighbors (1-4 neighbors) engaged in property mitigation. They were less enthusiastic when nobody else was participating, or on the other hand–when they perceived too many neighbors were clearing fuels. Shaded fuel breaks–like thinning treatments–were preferred to clearcutting. Read the article (open access) here: https://www.mdpi.com/2071-1050/13/21/11754/htm

Fuelbreak around Tanacross, Alaska

Molina A, Little J, Drury S, Jandt R. Homeowner Preferences for Wildfire Risk Mitigation in the Alaskan Wildland Urban Interface. Sustainability. 2021; 13(21):11754. https://doi.org/10.3390/su132111754

Jun 1 2020

Using Citizen Science to Help Monitor Air Quality–A Poster

The Environmental Protection Agency (EPA) has just ~15 official air quality monitoring sites around the immense area of Alaska to monitor air pollutants that can affect human health.   Wildfire smoke, for example, produced about 60,000 tons of PM2.5 in 2018 (400,000 acres were burned –just a moderate fire season for Alaska!)  If data from lower quality private and academic air sensors (called “Purple Air”) could also be used, we could add an additional 100 monitoring sites to better understand and forecast air quality.  NASA ABoVE scientists Allison Baer and Tatiana Loboda from the University of Maryland compared EPA and Purple Air sensor data and came up with calibrations that correlate extremely well (coded T&RH—see example graphic below).  You can view their Interactive Poster at the 6th ABoVE Science Team meeting—this week (Jun 1-4): https://astm6-agu.ipostersessions.com/default.aspx?s=09-98-87-A0-E6-1A-FA-E4-79-58-CF-F8-B6-54-4B-79

SiteCorrPurpleair-Baer

Example correlation from one private air quality monitoring station in Fairbanks.

Feb 21 2020

Upgrading Satellite Mapping of Burn Severity

As discussed in the Feb. 7 Fire Science Highlight, burn severity in Alaska is best related to the amount of consumption of the forest floor—not the degree of tree canopy mortality as is in temperate pine and fir forest.  Yet the most commonly applied metric to map burn severity using satellite remote sensing does not correlate well with substrate burn severity.  The change in Normalized Burn Ratio (dNBR; Key and Benson 2003) is based on comparing a pre- and a post-fire image. However, NBR thresholds for severity differ from one fire to another and among different years: similar numbers don’t indicate the same severity levels (D. Chen et al. 2020).  And with tundra fires, sometimes it works, other times not.  This problem has dogged fire effects and ecology studies in Alaska for some time (see list of papers in Sean Parks November 2019 presentation) leading French et al. (2008) to conclude: “Satellite remote sensing of post-fire effects alone without proper field calibration should be avoided.”

ARF63_0-50m_2008

2008 Transect photo from Anaktuvuk River tundra fire (R. Jandt)

Recently, we’ve seen some promising new methods used to improve satellite remote sensing of burn severity in boreal forest.  Whitman et al. compared several indices including a relativized index that facilitated comparisons between different fires in Canada.  She told us about it at the Opportunities to Apply Remote Sensing in Boreal/Arctic Wildfire Management and Science Workshop in 2017—here’s her presentation if you missed it: Improving Remotely Sensed Multispectral Estimations of Burn Severity in Western Boreal Forests.  Loboda et al. ( 2020) found single images using just NIR (near-infrared) bands of Landsat did better than NBR in discriminating tundra fire severity.  Sean Parks is attempting to harness the power of Google Earth Engines and cloud-based computing to use multiple images to further define the ecological burn severity (Parks et al. 2019)—this work is kicking off at the University of Montana.  He also found that unusual aspects of some fires in Alaska (pre-existing beetle kill, short fire return interval) contribute to poor performance of the standard index (see his recorded November, 2019, Association of Fire Ecology meeting presentation HERE).  And Yaping Chen, from the University of Illinois, explored using indices based on Visible and NIR bands (which have a large archive of available imagery going back to the early 1970’s) to evaluate tundra fire severity.  Her paper (Y. Chen et al. 2020) points to a VNIR index called GEMI as a “robust surrogate to NBR in Arctic tundra ecosystems, capable of accurately estimating fire severity across fire seasons, tundra fires, ecoregions, and vegetation types.”  The fact that GEMI is not as influenced by different vegetation types as dNBR gives it a distinct advantage mapping tundra burn severity.

Being able to more accurately map burn severity levels from space would give ecologists a boost for understanding why fires sometimes induce radical changes in ecosystems while other times the system self-replaces in a very short span.  For example, Yaping Chen used GEMI to reconstruct burn severity on older tundra fires like the 1977 example below and tie it to thermokarst effects (like catastrophic lake drainage or ponding) resulting from the fires (poster presented at AGU meeting December 2019).  We look forward to more exciting products and tools coming from these research teams!

Y. Chen et al. 2020, Fig. 7

Reconstructed fire severity map of the 1977 OTZNNW 38 tundra fire computed with dGEMI using Landsat MSS imagery.

Citations:

Chen, Yaping; Lara, Mark J.; Hu, Feng Sheng. 2020. A robust visible near-infrared index for fire severity mapping in Arctic tundra ecosystems. ISPRS Journal of Photogrammetry and Remote Sensing 159:101-113.

Chen, Dong; Loboda, TV.; Hall, JV. 2020. A systematic evaluation of influence of image selection process on remote sensing-based burn severity indices in North American boreal forest and tundra ecosystems. ISPRS Journal of Photogrammetry and Remote Sensing 159:63-77.

French, NHF.; Kasischke, ES.; Hall, RJ.; Murphy, KA.; Verbyla, DL.; Hoy, EE.; Allen, JL. 2008. Using Landsat data to assess fire and burn severity in the North American boreal forest region: an overview and summary of results. International Journal of Wildland Fire 17(4): 443-462.

Key, Carl H.; Benson, NC. 2003. The normalized burn ratio (NBR): A Landsat TM radiometric measure of burn severity. US Geological Survey Northern Rocky Mountain Science Center.

Loboda, Tatiana V.; Hoy, EE.; Giglio, L; Kasischke, ES. 2011. Mapping burned area in Alaska using MODIS data: a data limitations-driven modification to the regional burned area algorithm. International Journal of Wildland Fire 20(4):487-496.

Parks, SA.; Holsinger, LM.; Koontz, MJ.; Collins, L; Whitman, E; Parisien, MA; Loehman, RA.; Barnes, JL.; Bourdon, JF; Boucher, J; Boucher, Y; Caprio, AC.; Collingwood, A; Hall, RJ.; Park, J; Saperstein, LB.; Smetanka, C; Smith, RJ.; Soverel, NO. 2019. Giving ecological meaning to satellite-derived fire severity metrics across North American forests. Remote Sensing 11(14):1735.

Whitman, E, MA Parisien, DK Thompson, RJ Hall, RS Skakun, and MD Flannigan. 2018. Variability and drivers of burn severity in the northwestern Canadian boreal forest. Ecosphere 9(2):e02128. 10.1002/ecs2.2128

Mar 21 2019

Fire management adaptability in Alaska: as seen by the managers

Tait Rutherford and Courtney Shultz just published the results from the social science part of their Joint Fire Science Program (JFSP) funded study: Impacts of Climate and Management Options on Wildland Fire Fighting in Alaska—see full citation below. The paper seeks to understand strengths and weaknesses of the Alaska fire management process and how cooperating agencies are adapting to changes in the fire environment with warming climate. The data for the analysis came from 41 hour-long interviews with fire management decision-makers across Alaska, which were categorized and analyzed for common themes.

The authors note that “bridging” institutions can be “repurposed to meet new challenges” and can provide key assistance to more hierarchical federal and state agencies in adapting to new issues (including climate change). Examples of this in action at the national level were on display at the recent meeting of JFSP regional Fire Science Exchange Networks in Washington, DC. It was interesting how diverse the main business lines were in different regions. For example, Hawaii’s Pacific Fire Exchange focuses mainly on community protection and invasive species, several exchanges are deeply engaged in supporting training and workforce development to implement prescribed burns, and California Fire Science Consortium is gearing up efforts to help those already stricken by wildfire and looking into new closer working relationships with FEMA. Another example of “bridging” mentioned by several interviewees in Alaska was the Kenai Peninsula All-Lands All-Hands working group, which has been very instrumental in coordinating inter-agency fuelbreaks.

Rutherford, in summarizing manager’s views, notes that some challenges are enduring (like WUI protection) but a few emerging issues are also highlighted. For example, regarding subsistence use opportunities, participants indicated that the maintenance of wildlife habitat will require both using fire and fire suppression to support a diversity of age classes and forest cover types on the landscape. There is a growing recognition of the need for enhanced policy and management tools to support “point protection” of values like private lands and cabins, including improved data and interagency communication and efficient protection techniques. In short, the collection of viewpoints is very instructive about the “state of the art” of fire management as seen by the experts and executors of that art. A highlight of the paper is the Appendix, which includes 64 quotes from the interviews, allowing one to hear “from the horse’s mouth” about current priorities and challenges in Alaska fire management as well as potential future directions and requirements to meet new challenges.

Citation:  Rutherford, T. K., and C. A. Schultz. 2019. Adapting wildland fire governance to climate change in Alaska. Ecology and Society 24(1):27.

Download is Open Access at: https://www.ecologyandsociety.org/vol24/iss1/art27/

 

Nov 19 2017

Ecological Impacts of Forest Fuel Treatments in Alaska

Although vegetation treatments can reduce fire potential, they may have unintended ecological effects, but there has been little published on possible impacts—especially for Alaska. So the recent publication (Melvin, et al. 2017) of a study on interior Alaska rxbAA42_ks-sm2.jpgfuel treatments by an interdisciplinary team of researchers is an important addition to regional management resources. In fact, it probably represents the FIRST published paper specifically on how fuel-reduction affects carbon and nutrient pools, permafrost thaw, and forest successional trajectories. The analysis included 19 sites managed by numerous Alaska agencies covering a large swath from Nenana to Deltana, and were sampled at various ages from 2-12 years post-thinning or shearblading.  Our third AFSC Research Brief of 2017 is a digest of the study results.

Full Citation:  Melvin, A. M., et al. (2017), Fuel-reduction management alters plant composition, carbon and nitrogen pools, and soil thaw in Alaskan boreal forest. Ecol Appl. Accepted Author Manuscript. doi:10.1002/eap.1636

Jul 25 2017

Lightning Sparking More Boreal Forest Fires

Our Research Brief this month covers a new NASA-funded study led by Sander Veraverbeke of Vrije Universiteit  in Amsterdam which found lightning storms to be a main driver of recent large fire seasons in Alaska and Canada.  Results of the study are published in the July, 2017 issue of Nature Climate Change.

nclimate_Cover_JUL17

July 2017 Nature Climate Change

MODIS (Moderate-Resolution Imaging Spectroradiometer) satellite images and data from ground-based lightning networks were employed to study fire ignitions. Sander’s analysis found increases of between two and five percent a year in the number of lightning-ignited fires since 1975. Veraverbeke said that the observed trends are consistent with climate change, with higher temperatures linked to both more burning and more thunderstorms.

Study co-author Brendan Rogers at Woods Hole Research Center in Massachusetts says these trends are likely to continue. “We expect an increasing number of thunderstorms, and hence fires, across the high latitudes in the coming decades as a result of climate change.” This is confirmed in the study by different climate model outputs.

Charles Miller of NASA’s Jet Propulsion Laboratory in California, another co-author, said while data from Alaska’s agency lightning networks were critical to this study, it is challenging to use these data to verify trends because of continuing network upgrades. “A spaceborne sensor that provides lightning data that can be linked with fire dynamics would be a major step forward,” he said. Such a sensor exists already– NASA’s spaceborne Optical Transient Detector –but it’s geostationary orbit limits its utility for high latitudes.

The researchers found that the fires are creeping farther north, near the transition from boreal forests to Arctic tundra. “In these high-latitude ecosystems, permafrost soils store large amounts of carbon that become vulnerable after fires pass through,” said co-author James Randerson of the University of California, Irvine. “Exposed mineral soils after tundra fires also provide favorable seedbeds for trees migrating north under a warmer climate.”

The Alaska Fire Science Consortium at the University of Alaska, Fairbanks, also participated in the study, and provides this 2-page Research Brief executive summary.

Citation: Veraverbeke, S., B.M. Rogers, M.L. Goulden, R.R. Jandt, C.E. Miller, E.B. Wiggins and J.T. Randerson. Lightning as a major driver of recent large fire years in North American boreal forests. Nature Climate Change 7: 529–534 (2017). DOI: 10.1038/nclimate3329