Boreal Forest Fire Activity in Canada and Siberia During ARCTAS

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Boreal Forest Fire Activity in Canada and Siberia
During ARCTAS

• The ARCTAS Boreal Fire Team

Mike Fromm (Naval Research Laboratory) Brian
Stocks (B.J. Stocks Wildfire Investigations
Ltd.) Amber Soja (National Institute of
Aerospace) Rene Servranckx (Canadian
Meteorological Centre) Dan Lindsey
(NOAA/NESDIS/RAAMB)
with thanks to the ARCTAS Science Team
ARC-IONS Workshop Toronto, Canada, January 7-8,
2009
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Outline

• Boreal fire context Canada and SK
• Boreal fire behavior and column dynamics
• ARCTAS within context of 2008 fire season
• SK fire activity before and during ARCTAS

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Canadian Forest Fire Activity

• Annual burned area 0.3-7.5 million hectares
  large interannual variability (gt order of
  magnitude) complicates trend analysis
• Average annual number of fires 8000 since 1970
• Driven by
• Continental climate
• Extreme weather
• Multiple ignitions

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Seasonal CDN Large Fire Distribution

• June/July in high boreal
• Lightning fires
• Generally free burning
• Natural/essential

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Large Fires in Canada

• 3 of fires gt200 ha, 97 of area burned
• Large modified suppression zone (OBZ) where fires
  receive limited response focus here as fires
  burn naturally unlimited access
• Well within range from Cold Lake AB

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ARCTAS Summer
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2008 in SK and Canadian Context
2008 1997-2007
SK OBZ AB 746,219 265,051
Can OBZ AB 956,429 1,251,807
Can Total AB 1,642,884 1,946,310
78 of 2008 Canadian OBZ area burned occurred in
SK in 2008
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Fire Intensity/Energy Release

• Combine rate of spread/fuel consumption/heat of
  combustion to determine fire intensity (IHWR)
  resistance to control
• Savanna Fires
• 0.1-1.2 kg/m2
• 500-10,000 kW/m
• Lower convection columns
• Boreal/Temperate Forest Fires
• 2.5-5.0 kg/m2
• 100-100,000 kW/m
• gt fuel consumption intensity
• Towering convection columns reaching UTLS

A typical high-intensity boreal crown fire
convection column viewed from an altitude of 10
km (photo courtesy Mr. Todo, JAL)
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Boreal Fire Convection Column Dynamics

• Column is integrator of FC, RoS and intensity
• Column develops if rate at which thermal energy
  is converted to kinetic energy above the fire gt
  kinetic energy of windfield
• Reverse produces a wind-driven fire
• Buoyant, heated gases above fire rise and entrain
  surrounding cool air buoyancy the force through
  which fire thermal energy converted to kinetic
  energy of motion in column
• Height/dynamics of column function of atmospheric
  lapse rate and size/intensity of fire
• Columns attain full potential if winds
  decreasing/constant above fire, while higher
  winds aloft sheer off column
• Solid structure moving across landscape, blocking
  ambient wind, whirlwinds on lee side

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Convection Column Zones

• Fuel bed, combustion turbulence zones (up to
  100m)
• Fire convection zone up to base of convection
  column cap (from 300 to 6000m in height)
• Smoke fallout zone thin layer at base of
  convection cap
• Condensation convection zone or capping cumulus
  rising to top of column smoke still present in
  this zone

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2008 Canadian Fire Season

• Virtually no fires east of MB
• Light year in BC, AB,YK
• Early fires in MB in May
• Began early June in SK, NT
• Centered in OBZ
• Fires allowed to burn

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SK Fire Activity June 10/08
NOAA AVHRR 0207h June 11/08
pyroCB
MODIS Aqua 2015h UTC June 10/08
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SK Fire Activity June 11/08
MODIS Aqua 1920h UTC
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Mid-June precipitation slowed fire activity for
a period
June 15/08
June 18/08
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Our Role in ARCTAS

• Forecast fire occurrence and behavior
• Support aircraft missions
• Liaise with fire management agencies responsible
  for fires
• Monitor/document fire growth and column
  development with satellite imagery
• Forecast pyroCb development
• Monitor Siberian fire activity

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Fire Danger Conditions

• Monitor CWFIS outputs data from SK weather
  stations
• Forecast fire danger
• High to extreme in northern SK in early June,
  then tapering off with scattered showers,
  building again in late June

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FWI System Values during ARCTAS
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Summer ARCTAS Deployment Timeline of Smoke Plumes

• 1 7
  12
• June July

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AVHRR June 30 1931 UTC
OMI Aerosol Index
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June 30 2341 UTC
4 hours later
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June 28 smoke columns near Lake Athabasca 5-6 km
Photos courtesy P3 group
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Fires between Athabasca and Reindeer Lakes
June 30/08
5-7 km
Photos courtesy P3 group
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Typical pyroCb convection columns (10-12 km)
Typical pyroCb fire behavior continuous high-inte
nsity crown fires
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Small pyroCb near Norman Wells, NWT June 28/08
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Some precip Period during ARCTAS

• Scattered rainfall quieted fires
• So, quiet period before ARCTAS after June 12,
  then revived during first 5 days of ARCTAS, then
  quiet but rebuilding around Lake Athabasca and
  Pelican Narrows active

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Siberian Fires during ARCTAS

• Major fire year again in Siberia
• Began very early smoke detected during ARCTAS
  Spring Phase
• Lack of effective fire management due to economic
  problemswidespread exploitation of Russian
  forests
• Smoke transported to North America, including
  Arctic

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East Siberian Fires June 28/08
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East Siberian Fires June 30/08
Russian fires continue to grow Smoke thickening
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East Siberian Fires July 1/08
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East Siberian Fires July 2/08
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East Siberian Fires July 3/08
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10 km
7 km
6 km
13 UT
GOES vis 20080706 1100 UTC
11 UT
9 UT
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ARCTAS Science Meeting

• Will focus on relationship between fire
  danger/fire behavior and column heights on ARCTAS
  fires on sampling days
• Use fire growth maps and MODIS hotspot data,
  along with CDN Fire Behavior Prediction System
• Early results indicate that intense surface fires
  and intermittent crown fires were common during
  ARCTAS, resulting in plumes reaching 5-7 km in
  altitude

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June 29-July 8/08
July 9-18/08