Category New Publications

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

Mar 29 2016

Do bark beetle outbreaks really affect burning?

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It has long been assumed that bark beetle outbreaks on the Kenai lead to increased fire danger, even though beetle disturbance has been shown to have mixed effects on crown fire potential, fuel profiles and burn severity in the Rocky Mountains.  Winslow Hansen, doctoral candidate at the University of Wisconsin, recently published an analysis of beetle outbreaks and fire on the Kenai Peninsula between 2001-2014 (Hansen et al. 2016).  He looked at effects in pure white spruce stands–where duration of beetle attacks is longer and mortality greater–and in mixed white and black spruce stands common on the northern peninsula, where attacks are less severe.  His analysis indicates mixed effects:  severely damaged white spruce stands did not demonstrate increased fire occurrence (instead, % canopy cover appeared to drive likelihood of burning) while the mixed white/black spruce stands did show a positive correlation with beetle outbreaks and fire.  Winslow explores the reasons for this in his relatively short article:  worth reading.  You may remember Winslow from his previous work on beetles/fire effects and property values on the Kenai (recorded MS Thesis defense) and climate effects on fire regime (recorded 2015 presentation).

Citation:  Hansen, W.D, F.S. Chapin III, H.T. Naughton, T.S. Rupp, and D. Verbyla. 2016. Forest-landscape structure mediates effects of a spruce bark beetle (Dendroctonus rufipennis) outbreak on subsequent likelihood of burning in Alaskan boreal forest.  Forest Ecology and Management 369: 38–46.

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.

Jan 18 2016

Fuel Treatments Aid 2015 Firefighting Efforts in Alaska

A new report by USFWS Kenai Refuge fire staff (Nate Perrine) examines

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areas where the 2015 Card Street fire intersected completed fuels treatments. He utilized IFTDSS (Interagency Fuels Treatment Decision Support System) modeling to analyze the treatment effect on fire behavior, and also documented post fire effects within the treated areas. This well-illustrated discussion includes recommendations for future treatments and analyses–a must-read for fire fuels specialists in Alaska! Click below to download a pdf.

The Effects and Use of Fuel Treatments during the Card Street Fire

Jan 12 2016

Western Forester Article on Fuel Breaks in Alaska

The first 2016 issue of Western Forester contains a pair of short articles on the Nenana Ridge crown fire experiment and fuel break effectiveness at Funny River and the studies in progress on fuel break effectiveness in Alaska.  Eric Miller (BLM-Alaska Fire Service) and Nathan Lowjewski (Chugachmiut Forester) did a nice job on these write-ups!  Eric’s article gives the first published account of what happened in 2016 when wildfire challenged a 10-year old thinned fuel break in black spruce, as well as insight to the “hows” and “whys” of fire behavior in fuel breaks.  Here’s a link to the issue:  http://www.forestry.org/media/docs/westernforester/2016/WFJanFeb2016-2_LT3qttf.pdf

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The Yukon Hot Shot Crew puts finishing touches on experimentally thinned fuel treatment blocks in June, 2007 (R.Jandt).

Mar 20 2015

Ides of March–tidings of an early start to 2015 fire season

Capture-rickLate last year, Rick Thoman, NWS Climate Scientist in Fairbanks, predicted a warm winter for most of Alaska at his December 2014 NWS Webinar.  That forecast worked out pretty well, with Dec-Jan-Feb temperatures well above normal for that period all over the state! So what does he say now about the upcoming spring and start of Alaska fire season? At a March 19 forecast briefing for fire managers, Rick pointed out benefits of the newer “dynamic” climate models which continuously update their algorithms with the latest weather observations.  This kind of modeling requires major computing power so it’s only become

View Rick’s recorded monthly climate webinars posted on ACCAP’s website: https://accap.uaf.edu/?q=NWS_Briefings

possible in the last decade or so with availability of supercomputing centers.  The collection of multi-model ensembles he showed universally point to a warm or VERY WARM April (goodbye snow pack!) and that seems to extend out to the April-May-June outlook as well, with pretty good confidence.  One moderating influence in the forecast comes from mid-range precipitation outlooks from two independent forecast tools which call for above-normal precipitation, especially in the eastern Interior.  The missing link that fire managers would like to be able to forecast is convection (lightning), but Rick says that may be coming as climate modelers gain experience with the new dynamic models.  AICC Predictive Services has now posted their seasonal outlook for the 2015 Fire Season on the web, where you can learn about Modoki El Niño and what that may mean for fire season!Capture-cpc

 

Mar 13 2015

Where fire management and carbon studies connect . . .

Screen capture of the WFEIS calculator (http://wfeis.mtri.org)

On the surface Alaska fire management and boreal ecosystem carbon studies have little in common.  But a deeper look reveals the connections between them.  Carbon scientists in the last decade have become increasingly interested in fire effects on the legacy carbon locked up in permafrost and the deep, slow-to-decompose organic layer of boreal forest floor (Kasischke et al. 2013, Genet et al. 2013).  Projections indicating more extensive, frequent and/or severe fires in northern latitudes with a rapidly warming climate, longer fire seasons, and more lightning (Romps, et al. 2014) lend a certain urgency to attempts to quantify the potential impacts of fire-released carbon on greenhouse warming.  Fire management agencies are less interested in long-term impacts of fire-released gasses but they are more and more driven to assess impacts of smoke on communities.  Work at the boundary between the two sets of interests has started to yield some interesting results.  For example, Michigan Tech Research Institute has joined their consumption field data from NASA studies to the USFS Consume Model and FCCS fuels maps and LANDFIRE fire perimeters in a web-based tool that provides users a simple interface for computing wildland fire emissions (1-km spatial resolution). The Wildland Fire Emissions Information System (WFEIS) can calculate tons of CO2 or other gases from large fires across the US and Canada from 1984-2010.  Although this tool is  for post-facto emissions analysis it is a good example of how large spatial data sets and complex equations can be united in a simple graphical interface allowing one to–say–query the forest fire emissions from the 231,000 acres burned in Alaska in 2010 (10.9 million tons CO2, 95,000 tons PM 2.5).  The hope is that weather modeling and research linkages with the common fire danger and risk rating system used in northern latitudes (CFFDRS) will soon bring this kind of application into the real-time and forecast prediction realm.

Feb 17 2015

Does climate warming mean more lightning in Alaska?

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Fig. 1. Yearly and monthly number of lightning flashes in Alaska from 1986-2010 (Farukh and Hayasaka, 2012)

A recent article in Science magazine (Romps, et al. 2014) postulated a 12% increase in lightning strikes over the continental US for each degree C of warming.  If this model holds true for Alaska, we should have already seen an increase in lightning strikes of roughly 20% in interior Alaska over the last 25 years since summer temperature has warmed by about 2.5 F–up to 3.7 F north of the Brooks Range (data from UAF Geophysical Institute).  So, has anyone looked at the trends in Alaska’s Automatic Lightning Detection Data to see what has been observed?  AFS has been collecting this data (publicly available at http://fire.ak.blm.gov) since 1986. It turns out the answer is yes!  Drs.Farukh and Hayasaka (2012) published an article on how large lightning storms characterized some of our largest recent fire seasons including this figure.  I’d like to challenge other  investigators to look at the regional significance of this phenomenon in the state, which could be an important fire regime driver in boreal forest/tundra, with the data which is now complete (ALDS went offline in 2013, replaced by a time-of-arrival system)!

Jan 27 2015

Climate Change and Fire May Impact Northern Alaska Caribou Herds

Boundary Fire near the Canadian border 2005 (Photo: Tony Chapman, BLM Alaska Fire Service)

Will climate-driven changes in fire regime affect the Porcupine Caribou Herd? Caribou actively seek out and rely on high-energy lichen-rich habitats in the winter, and these lichen stands–also known as “caribou moss”– are uniquely sensitive to fire, requiring 60-100 years to recover after burning. Alaska climate modelers and biologists teamed up to study predicted annual acreage burned in the ranges of two northern herds: the Central Arctic Herd and the Porcupine Caribou Herd (of Arctic National Wildlife Refuge fame). Using newly developed models of wildfire response to climate changes, Gustine et al. (2014) modeled burn acreage in the next few decades under two possible climate trajectories: let’s call them “warm” or “hot”. Under the “warm” scenario they found little change through 2090 in the total old-growth habitats available to caribou of either herd. However, the “hot” climate scenario indicated fires grew larger, increasing average area of winter habitat that burned per decade. In brief, the Central Arctic Herd lost 11% of their winter habitat and the Porcupine Herd lost 21% through 2090 under the “hot” scenario. In addition, 30% of the Porcupine Herd’s current spruce forest habitat changed to a younger forest type or tundra. While biologists continue to debate how much habitat is required to sustain herds at present levels, habitat loss is rarely beneficial and availability of old-growth lichen stands is a big driver of caribou use patterns in most Alaska herds. If we humans have the power to rein in the pace of climate change to the “warm” scenario by slowing our greenhouse gas emissions, the caribou would probably appreciate it. This short illustrated paper is open access—read the whole research article at:

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0100588

Citation: Gustine, D.D., Brinkman, T., Lindgren, M., Schmidt, J.I., Rupp, T.S., and Adams, L.G., 2014, Climate-driven effects of fire on winter habitat for caribou in the Alaskan-Yukon Arctic: PLOS One, v. 9, no. 7 100588, doi:10.1371/journal.pone.0100588

Dec 19 2014

What is the Weather Outlook for Early Season 2015?

Rick Thoman, NWS Climate Scientist in Fairbanks, said “Save this one!” when he showed this slide about the CPC’s spring temperature prediction in his Dec. 19 NWS Webinar.  So I did:  it’s a pretty bold forecast for a warmer than normal early spring in much of Alaska.  Of course, it’s still hard to know what that might mean for fire season.  We know that warmer springs can be associated with premature disappearance of snow and higher fire danger in that pre-greenup season though.  On the other hand, well-timed spring rain, after the ground thaws enough to receive it, can just as easily put a damper on duff fuel moistures well into the summer.  And, it’s a lot easier to predict temperature than precipitation.  Still, when I hear the starting line-up:  PDO (Pacific Decadal Oscillation) in a warm phase, a fairly robust El Niño, and warm early spring–I can’t help but think that it could be an interesting year.  It looks like Southcentral Alaska may be in the cross-hairs again too.  Check out the latest seasonal outlooks as the season progresses at CPC’s website.

December 18th NWS prediction for spring temperature/precip in Alaska. See the latest at www.cpc.ncep.noaa.gov/products/predictions/90day/

December 18th Climate Prediction Center Forecast for spring temperature/precip in Alaska. See the latest at http://www.cpc.ncep.noaa.gov/products/predictions/90day/