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Forest Fires and Climate Change in Canada. Canadian Fire Statistics. Incomplete prior to 1970 Currently - average of 9000 fires a year burn 2.6 million ha Area burned is highly episodic 0.4 to 7.6 million ha Lightning fires 35% of total fires represent 85% of area burned Fire size
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Canadian Fire Statistics • Incomplete prior to 1970 • Currently - average of 9000 fires a year burn 2.6 million ha • Area burned is highly episodic • 0.4 to 7.6 million ha • Lightning fires • 35% of total fires • represent 85% of area burned • Fire size • 3% of fires are >200 ha • represent 97% of area burned
Large Fires in Alaska and Canada 1980-1999 Fire polygons kindly provided by Canadian Fire Agencies (Provinces, Territories and Parks Canada) and the state of Alaska
Forest Fires – 4 Key Factors • Fuel - loading, moisture, structure etc. • Ignition - human and lightning • Weather - temperature, precipitation atmospheric moisture and wind; upper atmospheric conditions (blocking ridges) • Humans - land use, fragmentation, fire management etc.
Fire and Carbon ~700 Pg carbon stored in the boreal forest ~30-35 % of the global terrestrial biosphere • Fire plays a major role in carbon dynamics: it can determine the magnitude of net biome productivity • 1) combustion: direct loss • 2) decomposition of fire-killed vegetation • 3) stand renewal: young successional stands have potential to be greater sinks than mature stagnant forests
Climate Change Projections • GCMs project 1.4 – 5.80 C increase in global mean temperature by 2100 • Greatest increases will be at high latitudes, over land and winter/spring • Projected increases in extreme weather(e.g., heat waves, drought, floods, wind storms and ice storms) • Observed increases across west-central Canada and Siberia over past 40 years Observations above – summer temperature changes below 2080-2100
Projected temperature changes vary considerably from year to year
A smoking gun? • Area burned in Canada is strongly related to human-caused warming • Impacts of climate change are here already • A warmer future means more fire in Canada
Area Burned Projections Hadley –3xCO2 Canadian –3xCO2 Projections of area burned based on weather/fire danger relationships suggest a 75-120% increase in area burned by the end of this century according to the Canadian and Hadley models respectively
Fire Occurrence Prediction • People-caused and lightning-caused fire occurrence • Models for Ontario suggest 25-100%increase in fire starts by 2090
Fire and WeatherFeedbacks: potentially positive Fossil Fuel emissions: increase greenhouse gases Cause warmer conditions Weather becomes more conducive to fire: more fire Carbon released from more fire enhances greenhouse gases further
Summary • Weather/Climate and fire are strongly linked • Fire activity is likely to increase significantly with climate change although the response will have large temporal and spatial variability • Integrated approaches will be required to adapt to climate-change altered fire activity in terms of social, economic and ecological policies and practices
Collaborators/Partners • Universities – Arizona, Australian National University, Manitoba, Montana, Toronto and UQAM/UQAT • BC Ministry of Forests, Environment Canada, NRCan, Ontario MNR and US Forest Service, • GCTE & IGBP • Action Plan 2000, Climate Change Action Fund,NCE – SFMN, National Center for Ecological Analysis and Synthesis, PERD
Proxy data also indicate that the recent warming is likely unprecedented in at least the past millennium Source: IPCC(2001)
Relative to 1961-90 average temperature Global surface temperatures are rising
Fire Ecology • Boreal forests survive and even thrive in semi-regular high intensity fires • Removes competition • Prepares seedbed • Survival strategies - Cone serotiny, vegetative reproduction and bark thickness • Role of fire suppression –Smokey syndrome
pessimist or optimist Climate change –
Fire Issues • An average of $500 million spent by fire management agencies in Canada a year on direct fire fighting costs • Health and safety of Canadians • Property and timber losses due to fire • Balancing the positive and negative aspects of fire
Fire and Climate Change Research – Purpose • Understand relationships between weather/climate and fire • Model future fire activity – fire weather, area burned, fire intensity/severity, fire season length etc. • Adaptation strategies for an altered fire regime due to climate change
Outline • Fire background • Climate change • Impacts of climate change on fire activity • How do we cope?
Fire and Climate Change Research – where are we? • Future fire weather – fire danger • Fire season length • Preliminary studies • Future area burned • Changes in fire intensity • Fire occurrence prediction • Level of protection studies • Adaptation plans
Length of fire season CCC –3xCO2 Hadley –3xCO2 • Fire season length increases by 10-50 days over much of the boreal according to theCanadian and Hadley GCMs
Potential Changes in Fire Intensity HFI Ratio 3x/1x CO2 0.0 - 0.2 0.2 - 0.4 0.4 - 0.6 0.6 - 0.8 0.8 - 1.0 1.0 - 1.2 1.2 - 1.4 1.4 - 1.6 1.6 - 1.8 1.8 - 2.0 2.0 - 3.0 3.0 + No fuel RCM - Ratio 3xCO2/1xCO2 Central Saskatchewan This will influence the type of fire (more crowning), reduce suppression effectiveness, and may lead to larger sized fires.
What will the future be like? • Longer fire seasons • More area burned • More intense fires • More ignitions – human and lightning-caused
Fire and Climate Change Research – where we are going • Better estimates of future area burned and GHG emissions • Fire Occurrence prediction – lightning and human-caused • Interactions with other disturbances • Understanding the effects of atmospheric and oceanic circulations on fire activity • Understanding processes & interactions using historical data
Health and safety of Canadians through improved fire weather and fire behaviour systems Options/strategic plans for landscape management Adaptation options for fire management agencies with respect to climate change altered fire regimes Fire season forecasts Input into decisions for Kyoto – are our forests carbon sinks or sources? So What!
We are living in a flammable forest Some Recent Incidents • Kelowna/Barriere, BC (2003) • Hillcrest/Blairmore, AB (2003) • Turtle Lake, SK (2002) • Chisholm, AB (2001) • Burwash Landing, YK (1999) • La Ronge, SK (1999) • Beardmore, ON (1999) • Shelburne County, NS (1999) • Badger, NF (1999) • Salmon Arm, BC (1998) • Swan Hills, AB (1998) • Granum, AB (1997) • Timmins, ON (1997) • Ft. Norman, NT (1995) • N&S Manitoba (1989)
How do we cope with more fire? • Greater risk – 1) Increased fire activity 2)More Canadians live and work in the wildland urban interface • More evacuations • Smoke issues – Health and transportation
spruce aspen Adaptation Strategies • Fire exclusion not an option in many regions • Landscape fuels management • Fuel conversion • Fuel reduction • Fuel isolation • “FireSmart” landscapes • Strategically located firebreaks • Education, prevention • Emergency planning • Level of protection studies
Sustainable Forest Management Future burn rate is lower than past burn rate:a real substitution is expectable. • Future area burned may be less than historical area burned in some regions • Natural Disturbance based Forest management could be used to recreate the forest age structure of fire-controlled pre-industrial landscapes Yield constraints
Fire and Kyoto • Fires contribute to greenhouse gases in the atmosphere • Currently our forests are a small sink of carbon or even a source of carbon due primarily to disturbances • If Canada includes forest management(Art. 3.4 – managed forests) then we will have to account for disturbances • Fire management protects values at risk – not carbon
Landscape Management - A Balancing Act • How much fire does the forest need? • New systems and models are needed to balance multiple objectives far a landscape with climate change altered disturbances( fire, insects, wind etc.) • Biodiversity (including Habitat) • Harvesting, exploration etc. • Tourism & Recreation • Carbon?