The National Interagency Fire Center (NIFC) has published a summary of the 1999 wildland fire season in the United States. For the convenience of the readers the GFMC staff has prepared an extract of the most important data and events of the year 1999 which – according to NIFC – will be remembered as a persistent fire season. Information from the U.S. Forest Service and the Virginia Department of Forestry are added.
The report of the National Interagency Fire Center provides a map of the Top Ten Largest Fires of the fire season 1999.
Fig. 1. Top 10 Largest Fires of the Season 1999 (as of 10 January 2000)
(Source: National Interagency Fire Center (NIFC))
Tab. 1. Top 10 Largest Fires of 1999
(Source: National Interagency Fire Center (NIFC))
(map)Location (State)Agency LandsHectaresDate
(from time of Report to Containment of the fire) 1 Nevada Bureau of Land Management
4-20 August 1999 2 Nevada Bureau of Land Management 90,855 5-12 August 1999 3 Nevada Bureau of Land Management 68,637 4-11 August 1999 4 Nevada Bureau of Land Management 68,480 4-20 August 1999 5 California Shasta-Trinity National Forest 57,039 23 August – 3 November 1999 6 Idaho Bureau of Land Management 56,217 3-7 August 1999 7 Nevada Bureau of Land Management 38,766 6-14 August 1999 8 Alaska Bureau of Land Management
and State Lands 37,235 12 June – 13 September 1999 9 California Los Padres National Forest 35,086 8 September – 18 November 1999 10 Nevada Bureau of Land Management 29,573 6-12 July 1999
A Ten-Year Wildland Fire Comparison Chart shows the number of wildland fires and the area burned from 1990 to 1999. Interesting is to note that over the 10-years period the interannual variation of burned area is more significant in comparison to the number of wildland fires.
Fig. 2. and 3. 10-year comparison statistics of number of fires and area burned (columns indicate acres!)
(Source: National Interagency Fire Center (NIFC))
The trend of constructing homes and other types of structures in wildland environments throughout the United States contains a potential of land-using conflict. The expansion of wildland/urban interface into the natural vegetation structures makes this locations extremely vulnerable to wildland fires. In 1999, 817 structures (residences and outbuildings) were destroyed by wildland fires from 13 states. Nearly 750 of those structures were burned in nine fires in California. One particularly devastating event was the Jones fire near Redding, California, where 428 structures were destroyed. The following overview map shows the destroyed structures in the United States in 1999.
Fig. 4. Map of destroyed structures (residences and outbuildings) by wildland fires in 1999
(Source: National Interagency Fire Center)
The following brief chapter is a one year extract of the 1999 Wildland Fire Season Summary by the US Forest Service Fire News on 23 December 1999.
Large fire activity began to increase in February in the southern part of the United States. In April and May, fire season in the South and East became very active. Fire activity in the western U.S. increased during the month of June; however, weather conditions kept activity lower than it might have been. The fire season in early July showed a typical pattern of activity with fires occurring in western Colorado and the Great Basin. By the second week in July, there were fires in California, Idaho and the Northwest, as well as on the George Washington and Jefferson National Forests in Virginia. By mid-month, nearly a million acres had burned in Alaska, mostly in areas that required minimal suppression efforts. Cooler, wetter conditions brought an end to Alaska’s fire season by the end of July. In Nevada and Oregon significant fire activities happened in August. Also in August large fire activity was reported in Virginia, New York, Kentucky, Texas, Utah, Idaho, Montana and Oklahoma. With little relief indicated in the long range weather forecast, large fires continued in the West into September. The persistence of dry weather into October kept firefighters busy. Large fires were common, especially in California. Finally, towards the end of the month, increased precipitation brought relief to northern California and much of the West, East and South. However, southern California and parts of the Great Basin remained dry and susceptible to large fires. Early November saw continued moderate fire activity across the country, with 22 states reporting large fires. In December, Santa Ana winds pushed fires out of control in southern California just days before the Christmas holiday. Most of the fires were contained within a couple of days.
The 1999 Wildfire Report from the Virginia Department of Forestry summarizes, that in 1999, 1,749 fires burned 4,900 ha which exceeded the number reported for each of the last twelve years. The leading cause of forest fires in Virginia is debris burning. Traditionally, Virginia experiences forest fire seasons in the spring and fall. The spring fire season begins in mid February and extends through April. The fall fire season usually covers a period of a few weeks in late October to mid November. However, in 1999 the spring fire season extended into the summer months. During the 1999 fire seasons, Virginia was experiencing a severe drought. The flammable conditions of the forest in the western part of the state were extreme. Drought conditions continued in the western part of the state despite hurricanes and flooding in the eastern part of the state. Forest fires occurring under these conditions burned erratically and were difficult to control and contain. Some fire had to be patrolled for weeks. Despite fires in Virginia the Department was able to send limited resources to Texas and Kentucky. The 1999 fire seasons exceed the previous five year average and was the signally the worst season since 1987.
Virginia Department of Forestry: Wildfire Report Summary 1999
In 1999, 1,749 fires burned 12,118 acres which exceeded the number reported for each of the last twelve years. The previous five-year average is 1,320 fires and 6,081 acres. The leading cause of forest fires in Virginia is debris burning.
Traditionally, Virginia experiences forest fire seasons in the spring and fall. The spring fire season begins in mid February and extends through April. The fall fire season usually covers a period of a few weeks in late October to mid November. However, in 1999 the spring fire season extended into the summer months. One of the largest fires of the year occurred on August 7th. The Purgatory Mountain Fire in Buchanan County burned 1,285 acres and cost over $166,000 to contain. A fire on Clinch Mountain in Southwest Virginia burned only 240 acres but cost over $97,000 to contain due to mountainous terrain and extreme drought conditions.
During the 1999 fire seasons, Virginia was experiencing a severe drought. The flammable conditions of the forest in the western part of the state were extreme. Drought conditions continued in the western part of the state despite hurricanes and flooding in the eastern part of the state. Forest fires occurring under these conditions burned erratically and were difficult to control and contain. Some fire had to be patrolled for weeks. The fall fire season continued until November 25 when rain finally reached western Virginia.
Despite fires in Virginia the Department was able to send limited resources to Texas and Kentucky. Virginia activated the Mid Atlantic Fire Fighting Compact in November.
The 1999 fire seasons exceed the previous five year average and was the signally the worst season since 1987.
These information were copied from the web site http://state.vipnet.org/dof/fire_rpt99.htm
California’s 1999 fire season
The fires that swept California last summer and fall cost the state at least $92 million, more than triple the California Department of Forestry and Fire Protection’s emergency reserve.
California’s 1999 fire season was one of the worst on record, with more than 7,000 wildfires burning at least 110,000 hectares. The CDF’s air tanker fleet spent 12,100 hours in the sky, 700 hours more than the previous record set in 1996.
The fires were aggravated by parched conditions and high winds, particularly in August and October, when firefighters’ spending averaged about $1 million every two days. In those two months alone, President Clinton issued emergency declarations for nine counties due to fires.
In Southern California, fire operations normally scaled back during the wet season in winter and spring were extended into the new year because of the threat from dry and windy conditions, a move that is costing the state roughly $1 million a month.
Authorities estimate the total cost to the state for emergency fire fighting for the state’s fiscal year, 1 July 1999, through 30 June 2000, will reach $145 million. Copyright 1999 by The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
In the 1999 forest fire season statistic the California Department of Forestry and Fire Protection (CDF) published detailed information on fire suppression cost, damage cost, structures destroyed, top five fires in areage burned and top five fires in structures lost.
Western Great Basin 1999 Season Overview
Weather and Fuels
Under the influence of La Nina, the fall and winter of 1998-99 saw mild temperatures throughout the Western Great Basin Area. While northwestern Nevada and the Sierra reported slightly above normal precipitation amounts in January and February, eastern and southern Nevada received very little precipitation, especially at the lower elevations. However, just enough precipitation had occurred in eastern and southern Nevada to trigger germination of the cheatgrass, which then out-competed the native grasses, shrubs and trees. In mid-April, fuel moistures in southern Nevada were 50% below the readings from the same period in 1998. By the end of May, southern Nevada was experiencing heavy initial attack activity due to cured fine fuels and below normal live fuel moistures in the sagebrush and pinion/juniper.
Green-up stalled until May in the northern half of the state as a result of below normal temperatures, while a heavy frost and snow at the end of May helped to add more fine, flashy, dead fuel biomass to the landscape as the new growth was killed. Warm temperatures in June combined with dry, windy surface conditions to promote early curing in the heavy (800 to 2,500 lbs/acre), continuous loadings of fine fuels that were present in north-central and northwestern Nevada. By July, all of the fine fuels had cured up to the 7,000 ft. level statewide. Extensive severity prepositioning of initial attack resources was done in anticipation of a heavy fire workload. Without these additional resources, the devastation of the 1999 season would doubtless have been even worse.
NFDRS Burning Indices (BI) and Spread Components (SC) reached all-time highs in 1999; the spread component numbers equated to a rate of spread in an advancing flame front of 2-3 miles per hour. Live and 1,000-hr. fuel moisture conditions continued to worsen in August under a pattern of single digit daytime relative humidities, poor nighttime humidity recovery (15-22%), and strong winds. Dry lightning provided the ignition source.
Advanced fire behavior became the norm and fires burned actively through the night. In mid-September, fire activity finally began to decrease as a result of shorter days and cooler nighttime temperatures.
35 Fire Weather Watch/Red Flag events resulted in a total of 157 Red Flag Warnings and 95 Fire Weather Watches being issued (all zones) between May and October. The National Weather Service also prepared 131 Spot Forecasts for wildfires.
Large Fire Activity
Large fire activity set the 1999 season apart, surpassing the 1994-1998 average of 44 large fires per year and eclipsing 1996’s total of 102 large fires. After several early season large fires in southeastern Nevada, monsoonal moisture helped to mitigate large fire activity in that portion of the state. From late June through mid-September, large fire activity throughout northern Nevada was nearly continuous, but the brunt of fire activity was felt in August. During the first week of August, dry lightning touched off 154 new fires. These fires resulted in roughly 1 million acres burned and the commitment of 75% of the United States= firefighting resources.
The last large fire of the season was controlled on November 28th. By that date, 113 large fires had burned a total of 1,642,484 acres (all agencies plus private). From 1994-1998, large fires represented an average of 4.6% of the total number of fires. By comparison, 9.7% of all fires in 1999 were at least 300 acres, with the largest single fire (Sadler) reported at 199,194 acres. 11 of the large fires were between 10,000 and 20,000acres in size, while 21 of the fires were 20,000+ acres. As is generally the case, large fires make up the majority of the total acreage burned; in 1999, large fires accounted for 87% of the total acres burned.
The 1999 season set new all-time records for the severity and breadth of fire damage. At 1,152, the total number of fires was 135% of the 5-year average, but the total of 1,870,285 acres burned was 773% of the 5-year average of 242,056 acres. More acres were burned during one 7-10 day period in August than had burned in any of the (entire) previous seasons on record.
Fire Rehabilitation Efforts
The extent of resource damage resulting from the 1999 season raised concerns that cheatgrass and other exotic species would continue to spread, native grasses and plants would decrease, erosion and riparian area damage would result, and a wildland fire cycle that will perpetuate the degraded condition of the Great Basin rangelands would ensue.
Even while much of northern Nevada=s large fire activity continued, Burned Area Emergency Rehabilitation (BAER) Teams were mobilized to assess the fire damage and provide recommendations for mitigation and restoration in accordance with existing land management plans. Team findings also included identification of areas to be green-stripped with perennial grasses in order to reduce the potential for large, devastating fires. A contract was issued for 5.4 million pounds of seed, covering 497,924 acres.
Figures about the total number and total number of acres burned of wildfires in the time period 1994-1999 can be accessed under the original website of the Western Great Basin Coordination Center.