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Fire in the news. Daily Statistics 7/10/02. Daily Statistics 7/10/02. Number of New Large Fires. Number of New Large Fires. Number of Fires. Number of Fires. Number of Active Large Fires. Number of Active Large Fires. Acres from Active Fires. Acres from Active Fires. Number of Acres.
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Daily Statistics 7/10/02 Daily Statistics 7/10/02 Number of New Large Fires Number of New Large Fires Number of Fires Number of Fires Number of Active Large Fires Number of Active Large Fires Acres from Active Fires Acres from Active Fires Number of Acres Number of Acres Fires Contained Yesterday Fires Contained Yesterday 3 Year-to-Date Statistics 1/1/02 - 7/10/02 3 46,062 20 10-Year Average 46,821 427,110 3,162,249 4 10-Year Average 46,062 Year-to-Date Statistics 1/1/02 - 7/10/02 427,110 10-Year Average 3,162,249 46,821 4 20 10-Year Average 1,414,305 1,414,305 The 2002 fire season How does it compare? Number of fires 67,128 10-year average 106,400 Total year 2000 122,827 Area burned (ha) 2,681,217 10-year average 1,666,672 Total year 2000 3,437,648 National Interagency Fire Center data, 28 October 2002)
Heard at recent meetings “Forests in the West are out of balance.” “A century of fire suppression has destroyed the ecological resilience of forests.” “Fuels have accumulated to catastrophic proportions.” “We need to reintroduce fire to maintain healthy forests.” “We need to thin our forests to restore their health and reduce fire hazard.” “Management should focus on bringing forests back to a natural fire regime.”
Traditional perspective: pyrophobia Revisionist perspective: pyrophilia
Current conditions Target conditions
Thinning Burning
Reconstruction of fire occurrence From Allen et al. (2001)
Tools for reducing fire hazard Mechanical thinning Prescribed burning
DO FUEL TREATMENTS REDUCE THE RISK OF CROWN FIRE? 5% of fires burn 95% of the area Few data that quantify how fuel treatments alter fire behavior Few guidelines on kinds and level of fuel reduction needed to reduce crown fire under severe fire weather
Assumptions about fire and fuels “Historic data show that wildfires are getting larger and becoming more intense.” – Forest Service Southwest Region web site Assumption 1: Fires are larger and more severe than prior to the 20th century Assumption 2: The size and intensity of wildfires are controlled by fuel accumulations
Wildland Fires in the United States 1920 - 2000 Source: National Interagency Fire Center database
Influence of climatic variability on fire Large fires in the Canadian Rockies are caused by high pressure blocking systems (Johnson & Wowchuck 1993) Forest fire behavior is determined primarily by weather variation among years rather than fuel variation associated with stand age (Bessie & Johnson 1995) Regional increases in wildfire extent in the Pacific Northwest are associated with the formation of a high-pressure blocking ridge over western North America throughout the fire season (Gedalof et al., in prep.)
Rapid fire spread and crown fire behavior occur during severe fire weather conditions Hayman Creek Fire Temperature 32-38 C Relative humidity 10-20% Winds 50+ kph Embers carried 5 km
Managing fire and fuels is mostly a sociocultural challenge Federal fire suppression cost in 2000 = $1.3 billion ($500 per ha burned)
Colorado wildland- urban interface
Rocky Mountain News Towns in harm’s way grew in 90’s Increase put people in danger from Hayman Fire By Burt Hubbard, News Staff Writer June 13, 2002 The foothills communities most threatened by the Hayman Fire were growing faster than most of Colorado in the 1990’s, putting thousands more people in harm’s way. The areas facing evacuation from the Hayman Fire added about 7,000 residents and 3,000 homes during the decade. And the area became home to more year-round residents as the percentage of seasonal housing fell, according to the U.S. Census data.
The restoration task Fire condition class – fire regime GREEN = Near historical range YELLOW = Moderately altered RED = Significantly altered
What is the historical context for restoration? vs. Does it matter?
Making decisions: Which values do we want to protect? Houses and structures Timber Water quality Air quality Wildlife Recreation (Or maybe we just like open forests)
Many constraints to effective fuel treatments Need lots of tree removal Lack of markets for small wood EIS, EA and other review Litigation Risk of escaped fire Scheduling (~20-year cycle)
Additional constraints Air quality People don’t like smoke Regulatory issues Carbon emissions Emissions from burning Wood processing waste
A rational approach to fire management and fuel reduction: Focus on the wildland-urban interface Benefits Focus fuel treatment area Protect high economic value Reduce liability Reduce fire suppression cost Respond to political concern Create defensible zones
Urban and exurban firebreaks “Only ewes can prevent forest fire”
How do we manage fuels at large spatial scales? Interface MOD. TREATMENT Wilderness NO TREATMENT Firebreak Private land NO FUELS Multiple values LOW TREATMENT
Toward science-based fire management and policy Develop guidelines that quantify the effects of fuel treatments on fire behavior Integrate scientific information and human values (ecological + cultural restoration) Develop a rational economic approach Educate the public on living with fire