Fire Research in the Boreal Zone of Eurasia and North America
Contributed by B.J. Stocks, Canadian Forest Service, J.-G. Goldammer; Max Planck Institute for Chemistry, Germany, and D.R. Cahoon and W.R. Cofer, NASA Langley Research Center, USA

A Note from the Chair

Science Features
2 BIBEX
3 STARE, TRACE-A, and SAFARI
7 Satellite Fire Monitoring
9 EXPRESSO
11 Domestic vs. Wild Fires in Africa
13 Boreal Forest Fire Research
15 GFMC and BIBEX
16 SAFARI-2000
19 BIBEX in the Future
Introduction
The world's total boreal forests and other wooded land within the boreal zone cover 1.2 billion hectares (ha) of which 920 million ha are closed forest. The latter number corresponds to about 29% of the world's total forest area and to 73% of its coniferous forest area. The majority of the boreal forest lands (taiga) of Europe and Asia are located in Russia. The Russian Forest Fund comprises about 1,181 million ha out of which 1,111 million ha are under the control of the Federal Forest Service. The carbon stored in boreal ecosystems corresponds to around 37% of the total terrestrial global carbon pool (plant biomass and soil carbon). Thus, the magnitude of the boreal forest area suggests that it may play a critical role in the global climate system, e.g., as potential sink or source of atmospheric carbon.

Statistics compiled by the Russian Federal Forest Service show that between 17,000 and 33,000 forest fires, mainly human-caused, occur each year, affecting up to 2 million ha of forest and other land. Since fires are monitored (and controlled) only on protected forest and pasture lands, it is estimated that the real figures on areas affected by fire in Asia's boreal vegetation is much higher. Observations from satellites indicate that during the 1987 fire season approximately 14.5 million ha were burned (Cahoon et al., 1994). In the same fire season about 1.3 million ha of forests were affected by fire in the montane-boreal forests of Northeast China, south of the Amur (Heilongjiang) River (Goldammer and Di, 1990).

Forest fire is also the dominant disturbance regime in Canadian boreal forests, and is the primary process organizing the physical and biological attributes of the boreal biome, creating an ecosystem largely dependent on periodic fire for its existence. Canada has 418 million hectares of forested land, 218 million hectares of which are capable of producing commercial forest products. In Canada, over the past two decades, an average of ~9000 fires have occurred yearly, burning an average of ~2.8 million hectares annually, although annual area burned is highly episodic, and has varied by an order of magnitude (e.g., 0.67 million hectares in 1997, 7.28 million hectares in 1995). Large areas of northern Canada, primarily non-commercial forest, receive a modified form of fire management, where fires are allowed to burn naturally unless they threaten commercially valuable stock; this fire management policy contributes significantly to the large areas burned in the boreal regions of Canada (Stocks et al., 1996).

The Fire Research Campaign Asia-North (FIRESCAN)
The Fire Research Campaign Asia-North (FIRESCAN) was initiated in 1992. FIRESCAN addresses the role of fire in boreal ecosystems and the consequences for the global atmosphere and climate. On 6 July 1993 a large forest fire experiment was conducted on Bor Forest Island, Krasnoyarsk Region, Russia. The major objective of the Bor Forest Island Fire Experiment was to conduct a high-intensity, stand replacement fire that would permit the documentation of fire behavior and effects in a manner that would allow comparison of eastern and western fire research methodologies. The major parameters investigated comprised:
  1. Fire ecology of Pinus sylvestris forests of the Sym Plain, including the long-term pollen and sediment records and a dendrochronology-derived fire history
  2. Vegetation and fuels (pre-fire and post-fire recovery, fuel loading and consumption, tree mortality)
  3. Fire behavior (fuels, fire weather, fire behavior)
  4. Emissions of gases (CO2, CO, H2, CH3Br, CH3Cl) and aerosol (particle deposition)
A high-volume sampling system was installed on an Aeroflot MI-8 helicopter and used to collect smoke samples immediately above the Bor Forest Island Fire. Particle-filtered samples were drawn through a probe mounted on the nose of the helicopter. This probe was coupled to a high-volume pump inside the helicopter by flexible hose. In thirteen smoke sampling runs three fire stages were analyzed: flaming combustion during the surface fire phase (F1), flaming combustion during the high-intensity crowning phase (F2), and smoldering phase (S3). Of major interest is the fact that samples collected during the high-intensity phase (F2) of the Bor Island Fire revealed elevated carbon monoxide emission ratios, suggesting lower combustion efficiency than previously inferred from results obtained from Canadian boreal logging slash fires during flaming combustion (Cofer et al., 1990). Methane and hydrogen emission ratios, however, were similar to measurements obtained in the Canadian fires. During the smoldering combustion phase (S3) carbon monoxide emission ratios were almost three times higher than on Canadian logging slash fires.

To complement the NASA trace gas emissions measurements, both helicopter and ground-based grab sampling (using stainless steel vacuum canisters) of emissions for specific analysis of methyl bromide (CH3Br) and methyl chloride (CH3Cl) was also carried out during the Bor Forest Island Fire. The emission ratios of CH3Br and CH3Cl measured in the Bor Forest Island Fire were in the range of 1.1-31x10 -7 and 0.2-12 x10-5, respectively. This was considerably higher than those found in savanna and chaparral fires or in laboratory experiments (Manö and Andreae, 1994). Highest values were found over smoldering surface fuels. This can be explained by the lower combustion efficiency of the smoldering process when compared to the prevailing flaming combustion of grass-type fuels.

In connection with the lake sediment coring investigation, a study of the dispersion of particles emitted from the Bor Island Fire was also undertaken. A series of traps was arrayed along three transects radiating away from the burn into the surrounding fen, in order to estimate the production and transport of "large" (10 µm) particles. Total particle fluxes and particle size distributions were determined using microscopy and image analysis.

The complete results of the experiment are published in the pages of FIRESCAN (1996) and Cofer et al. (1996).

Satellite data archive evaluation
NOAA AVHRR imagery is being used to map burned areas in the Russian boreal forest. The use of the AVHRR imagery can provide a continuous and consistent record of burned area each year and provides a basis for modeling carbon cycling in the boreal forest. The NOAA AVHRR instrument has been in operation since 1979. Since that time, there is an almost continuous archive of mid-afternoon imagery. Despite its poor resolution (~4-km nadir), this imagery has been demonstrated to be very suitable for monitoring boreal fire activity. The reason that the 4-km imagery is suitable for mapping fires in the boreal forest is that most of the area burned is by the larger fires that are easily detectable. We have collected imagery that spans the decade of the 1980s and we have begun to analyze the imagery to map the area burned each year. The mapping of the burned area is a multi-step process that begins with the radiometric correction of each scene. Each corrected scene is classified to reveal the burned areas, which are then mapped by region. Each regional burned area map is further analyzed to calculate the total area burned. Other products, such as clear-sky coverage and active fire maps are produced at the same time to aid in the assessment of the burned area estimates and burned area locations. We anticipate that much will be learned about fire trends and fire patterns during the 1980s in the Russian boreal forest.

Typical high-intensity boreal crown fire behavior during the 1998 phase of the International Crown Fire Modeling Experiment in Canada's Northwestest Territories.

The International Crown Fire Modeling Experiment
Conceived following the Bor Forest Island Fire Experiment in central Siberia, the International Crown Fire Modeling Experiment (ICFME) has been underway in the Northwest Territories of Canada over the past four years. The ICFME is being conducted under the auspices of the Fire Working Group of the International Boreal Forest Research Association (IBFRA), established in 1992 to foster cooperative research into the role of fire in northern circumpolar boreal forests (Fosberg, 1992).

Wildland fire research scientists in Canada and the United States had worked independently for many decades on the development of fire danger rating and fire behavior prediction systems which are currently in widespread use across North America and overseas. Although these systems are considered the best in the world, the development of a predictive physical model that could encompass the full range of fire behavior encountered in nature had proven an elusive goal for both Canadian and American fire scientists, and by the early 1990s, they began increasing their collaborative research activities in this area. At the same time, after decades of isolation caused by the Cold War, western and Russian fire scientists began meeting to discuss research methodologies and the possibility of working collaboratively. The first product of this new initiative was the Bor Forest Island Fire Experiment, but additional joint investigations were also developed, including the remote sensing of boreal fires, fire danger rating, fire behavior modeling, and climate change/forest fire/carbon budget impacts research. Clearly, for a number of converging reasons, the timing was opportune for the development of a large-scale international investigation of high-intensity fire behavior, and the ICFME was born.

The ICFME study area is located 40 km northeast of Fort Providence in Canada's Northwest Territories (61.6° N x 117.2° W), in a dense 65-year-old stand of jack pine (Pinus banksiana Lamb.), 12 m in height, with a black spruce (Picea mariana (Mill.) BSP) understory - a fuel complex ideally suited to the generation of high-intensity crown fires. A series of ten burning plots, the majority averaging 2.25 ha in size (150 x 150 m), were located at this site in 1995. After extensive preburn sampling in 1996, five experimental crown fires were conducted during the 1997-98 period, three in July 1997 and two in July 1998. All fires exhibited typical boreal forest high-intensity crown fire behavior: spread rates of 2-3 km/hr, fuel consumption levels of 40-50 tonnes/ha, flame heights ~30m, and energy release rates of 35,000-70,000 kW/m. These fires are the most complex, heavily instrumented experimental crown fires ever conducted. Ground-, tower-, and aircraft-based instrumentation, including continuous video, was used to measure, among other things, in-stand and above-stand radiation fluxes, vertical temperature profiles, spread rates, fuel consumption, fire residence times, and trace gas/aerosol emissions.

While the initial impetus for ICFME was the development of a physical model of the initiation and propagation of crown fires, this experiment has provided the opportunity to examine other aspects of the implications of crown fire behavior, including linkages to firefighter safety and wildland-urban interface concerns. Heavily instrumented fire shelters and housing structures have been tested on the ICFME crown fires to develop new protection standards for both firefighters and communities. Over the past two years, seven new burning plots were established to address these issues.

While the ICFME primary participating agencies are the Canadian Forest Service, the United States Forest Service, and the Government of the Northwest Territories, the list of additional collaborators actively participating in ICFME is growing. This group currently includes the Russian Forest Service, the National Aeronautics and Space Administration, the Government of Alberta, the Max Planck Institute for Chemistry, the National Institute of Standards and Technology, Storm King Mountain Technologies, Duke University, Montana State University, and the University of Alberta. The ICFME has also attracted media attention, including film/video companies from England and Austria.

Further experimental fires are planned for 1999 and beyond. Data exchange workshops are planned, and ICFME science results will be published in a dedicated volume within the next few years. Two overview/progress reports have been produced (Alexander et al. 1998a; Alexander et al. 1998b). In addition, a dedicated ICFME web site has been established that includes daily updates during the field program along with background and progress reports.

A third IBFRA/IGAC/BIBEX experimental boreal fire initiative is FROSTFIRE, a 1999 experiment involving a watershed burn (800 hectares) near Fairbanks, Alaska, designed to investigate fire/climate/permafrost/hydrology interactions.

References
  1. Alexander, M.E., B.J. Stocks, B.M. Wotton, M.D. Flannigan, J.B. Todd, B.W. Butler, and R.A. Lanoville, The International Crown Fire Modeling Experiment: an overview and progress report, In Preprint Volume Second Symposium on Fire and Forest Meteorology, 20-23. Amer. Meteor. Soc., Boston, MA, 1998a.
  2. Alexander, M.E., B.J. Stocks, B.M. Wotton, and R.A. Lanoville, An example of multi-faceted wildland fire research: the International Crown Fire Modeling Experiment, In Proc. Third International Conference on Forest Fire Research, Coimbra, Portugal, November 16-19, (in press). 1998b.
  3. Cahoon, D.R., B.J. Stocks, J.S. Levine, W.R. Cofer, and J.M. Pierson, Satellite analysis of the severe 1987 forest fires in northern China and southeastern Siberia, J. Geophys. Res., 99 (D9), 18627-18638, 1994.
  4. Clark, J.S., J. Lynch, B.J. Stocks, and J.G. Goldammer, Relationships between charcoal particles in air and sediments in west-central Siberia, The Holocene 8(1), 19-29, 1998.
  5. Cofer, W.R., E.L. Winstead, B.J. Stocks, L.W. Overbay, J.G. Goldammer, D.R. Cahoon, and J.S. Levine, Emissions from boreal forest fires: Are the atmospheric chemical impacts underestimated?, In Biomass Burning and Global Change, Vol. II, (ed. J.S.Levine, ed.), 834-839, MIT Press, Cambridge, MA, 1996.
  6. FIRESCAN Science Team, Fire in ecosystems of boreal Eurasia: The Bor Forest Island Fire Experiment, Fire Research Campaign Asia-North (FIRESCAN), In Biomass Burning and Global Change, Vol. II (ed. J.S.Levine), 848-873, MIT Press, Cambridge, MA, 1996.
  7. Fosberg, M.A., International Boreal Forest Research Association, Stand Replacement Fire Working Group, International Forest Fire News No. 7, 68, 1992.
  8. Goldammer, J.G., and X.Y. Di, The role of fire in the montane-boreal coniferous forest of Daxinganling, Northeast China: A preliminary model, In Fire in Ecosystem Eynamics: Mediterranean and northern perspectives, (ed. J.G. Goldammer and M.J. Jenkins), 175-184. SPB Academic Pub., The Hague, 1990.
  9. Goldammer, J.G., and V.V. Furyaev (eds.), Fire in Ecosystems of Boreal Eurasia, Kluwer Academic Pub., Dordrecht, 528 pgs., 1996.
  10. Steffen, W.L., and A.Z.Shvidenko (eds.), The IGBP Northern Eurasia Study: Prospectus for Integrated Global Change Research, The International Geosphere-Biosphere Program: A Study of Global Change, International Council of Scientific Unions (ICSU), IGBP Stockholm (English 95 pgs.; Russian 108 pgs.), 1996.