The Wildland Fire Assessment System (WFAS) is a contribution of “The Fire Behavior Research Work Unit”, Missoula (Montana USA). The broad area component of the Wildland Fire Assessment System (WFAS) generates maps of selected fire weather and fire danger components. Fire Danger (Potential) is a normalized adjective rating class across different fuel models and station locations. It is based on information provided by local station managers about the primary fuel model, fire danger index selected to reflect staffing level, and climatological class breakpoints. Low danger (class 1) is green and extreme potential (class 5) is red.
Several active fire signals were recorded by NOAA/OSEI with the NOAA-14 POES AVHRR HRPT satellite on 21 March 2000 in the southeastern US.
Fig.3. A number of heat signatures (red) ) and smoke (light blue) can be seen from fires burning in Florida, Georgia, and Alabama. Some of these may be from controlled burns.
Wildland Fire Update (17 March 2000)
The National Interagency Fire Center (NIFC) provides new data of the current wildland fire season in the United States. These data were analysed after different geographic regions. Further, a five-year wildland fire comparison statistic shows the number and the area of wildland fires from 1996 to 2000.
Although wildland fire activity decreased during the past week, extreme fire conditions remain in California, Arizona, New Mexico, Texas, Illinois, and Virginia. In the first 77 days of 2000, over 0.5 million acres ( 202,343 ha) have been affected by wildland fires. This figure is nearly three times greater than the four-year average of 185,000 acres (74,867 ha) burned by this time of the year.
While burning conditions in some states are severe, other states throughout the country are experiencing ideal conditions for prescribed fires. As of today, nearly 400,000 acres (161,874 ha) of wildlands have been treated by prescription fires. Prescribed fires are planned under specified conditions intended to improve the health of the natural landscape and/or reduce hazardous build-up of vegetation that lead to devastating wildland fires.
Long-range, 30-day weather forecasts are predicting above-normal temperatures and below-normal precipitation for the southern tier of states from southern California to Florida and throughout the Midwest (see Fig.4. 30 and 90-day forecast maps).
Keetch-Byram Drought Index (KBDI) by Florida’s Division of Forestry / Forest Protection Bureau
John Keetch and George Byram developed the K/B index at the Southern Forest Fire Laboratory to evaluate the effects of long-term drying on litter and duff and subsequently, on fire activity (1968). The index is based on a measurement of 8 inches (20 cm) of available moisture in the upper soil layers that can be used by vegetation for evapotranspiration. The index measure is in hundredths (0.01) of an inch of water and has a range of 0 through 800, with 0 being saturated and 800 representing the worst drought condition. The index indicates deficit inches of available water in the soil. A K/B reading of 250 means there is a deficit of 2.5 inches (64 mm) of ground water available to the vegetation. As drought progresses, there is more available fuel that can contribute to fire intensity.
For further information on the KBDI please refer to Keetch-Byram Drought Index Revisited: Prescribed Fire Applications.
Fig.5. Keetch-Byram Drought Index Map of Florida, 21 March
(Source: Florida Division of Forestry)
The Florida Forest Fire Weather Index (FWI) System consists of six components that account for the effects of fuel moisture and wind on fire behavior. The first three components are fuel moisture codes that follow daily changes in the moisture contents of three classes of forest fuel with different drying rates. The last three components are fire behavior indexes, representing rate of spread, amount of available fuel, and fire intensity; their values increase as fire weather severity increases. For detailed information on the Florida Fire Management Information System (FFMIS) the GFMC would like to refer to the original website.
According to the FFMIS for 21 March these parameters show various fire weather conditions for Florida.
Fine Fuel Moisture Code
Duff Moisture Code
Initial Spread Index
Fire Weather Index
Fig.6.-11. Output maps of the FFMIS, 21 March 2000
(Source: Florida Forest Fire Weather Index (FWI) System)
Southern Area Coordination Center (GA-SAC): We were still experiencing computer server problems yesterday. The Assessment Team will travel to Atlanta tomorrow. They will start working out of the Regional Office on Thursday, March 23rd. The tentative closeout for the Assessment Team is expected for Tuesday, March 28th. Potential Assessment forms are due from the all Coordination Centers by Thursday, March 30th (forms will be sent out today if the server s working properly). There is a low pressure system which is providing above average temperatures. Today, the highs will be in the 70s to 80s. Isolated thunderstorms are expected later this afternoon and evening over far west Texas. The forecast for tomorrow in Texas is a severe storm with possible hail.
Southeastern and South Central Compact: No fire activity reported.
Alabama Interagency Coordination Center (AL-AIC): The fire alert for Mobile and Baldwin counties was cancelled yesterday at 0800.
National Forests of Alabama (Al-ALF): The Forests received rain throughout the weekend ranging from 1.60 to 4.34 (40-110mm). The humidity is now 2 up to 256.
Arkansas/Oklahoma Interagency Coordination Center (AR-AOC): The weather forecast is predicting showers and thunderstorms moving through the area on Tuesday night.
Buffalo National River (AR-BUP): The Buffalo National River Prescribed Burn Module is committed to the Pea Ridge National Park in Arkansas.
Florida Interagency Coordination Center (FL-FIC): The burn ban is still in effect.
Florida Division of Forestry (FL-DOF): Throughout the weekend fire activity amounted to 257 acres (104 ha). The Benton Fire has 41 personnel on the fire
Chattahoochee-Oconee Natoinal Forest (GA-CHF): The Forest reports no fire activity.
Kentucky Interagency Coordination Center (KY-KIC): The fire danger has decreased due to receiving .18 to 2.0 (4-50mm) of rainfall. The forecast is for seasonal temperatures and sunny skies which will dry out fuels. Fire danger is expected to return to moderate by Wednesday. Helicopter 42CA is available at Big Swag Helibase.
Mississippi Interagency Coordination Center (MS-MIC): There is a resource order for a Supervisory Dispatcher position. Three helicopters were moved into the state.
North Carolina Interagency Coordination Center (NC-NCC): The Asheville Hotshots are available.
North Carolina Division of Forest Resources (NC-NCS): The State received fire activity over the weekend.
National Forests of North Carolina (NC-NCF): The Forest received 3 fires over the weekend and all fires were started by a train.
Tennessee Interagency Coordination Center (TN-TNC): The area is expecting fire danger by Wednesday.
Tennessee Division of Forestry (TN-TNS): The State reported some fire activity over the past weekend.
Cherokee National Forest (TN-CNF): The Forest received fire activity over the weekend. Last night the Forest received rain ranging from 1.5 to 0.5. (12-38mm)
Texas Interagency Coordination Center (TX-TIC): The area is to expect showers and thunderstorms in the far west.
According to the Incident Management Situation Report three categories of fires are distinguished, such as:
2. Prescribed Fires
3. Wildland Fire Use Fires**
* This classification corresponds to the category “wildland fires” as defined by the National Interagency Fire Center (NIFC)
** A brief excursion to wildland fire terminology:
Wildland Fires: Fires occurring on any tpye of vegetation, regardless of ignition sources, damages or benefits.
Wildfire: Any uncontrolled wildland fire which (1) may require suppression response, or (2) any uncontrolled wildland fire which meets management objectives and is declared as a Wildland Fire Use Fire (see below) or syn. Prescribed Natural Fire or Prescribed Fire.
Prescribed Fire: Occasionally also called management-ignited fire, or prescribed burning, is a controlled application of fire to vegetation in either their natural or modified state, under specified environmental conditions which allow the fire to be confined to a predetermined area and at the same time to produce the intensity of heat and rate of spread required to attain planned resource management objectives.
Wildland Fire Use Fire: Naturally ignited fire which is managed to achieve resource benefits under close supervision (syn. Prescribed Natural Fire)
Incident Management Situation Report (17 March 2000):
Initial attack and large fire activity in the Southwest, Southern, and Eastern Areas has been light to moderate since Monday. Demobilization of resources from the Southern Area is continuing. Very high to extreme fire indices were reported in Mew Mexico, Arizona, Texas, Virginia, California, and Illinois.
New Mexico – variable cloudiness will move into the state Monday and Tuesday. Conditions will be breezy and a little cooler, with a chance of showers and mountain snow showers. Wednesday and Thursday will continue cooler with a chance of showers.
Northwest Arizona will be breezy. High temperatures will range from the low 50’s (10°C) in the mountains to the 90’s (30°C) in desert areas. There is a chance of showers in central and northeast Arizona on Monday and Tuesday, with cooler temperatures. On Wednesday and Thursday, the southwest and south-central parts of the states will have below normal temperatures and a chance of showers.
Southern California coastal areas will be mostly clear to partly cloudy except for overnight low clouds and fog, with high temperatures in the mid 70’s (24°C). The desert areas will be mostly clear and breezy over the weekend, with highs from the mid 60’s (20°C) to the upper 70’s (26°C). Monday through Thursday will be partly cloudy with increasing winds and below normal temperatures. Southern California mountainous areas will be mostly clear and windy, with high temperatures in the 50’s and 60’s (10-20°C). Partly cloudy conditions will move in on Monday.
Indiana: Monday through Thursday will be partly cloudy and warmer, with highs from the mid 50’s to lower 60’s (10-20°C).
Missouri: Monday through Thursday, conditions will be clear to partly cloudy and warmer, with highs to the mid 60’s (25°C).
Tab.2. Fires and area burnt year-to-date (17 March 2000)
(Source: Incident Management Situation Report)
At this time of the year prescribed burning operations are conducted routinely.
Fire is an important natural tool for ecosystem management. It can reduce dense vegetation improving wildlife habitat and lessening the potential for large, wildfire disasters. Land managers are directed to prepare a prescribed fire/burn plan for every area of public land that can burn. Some areas require total suppression while others will benefit from a wildland fire. Those areas that will benefit from a fire can be treated by a prescribed fire.
Especially, for the moment, in the southern and southeastern regions of the United States prescribed fire activities will be carried out in the following weeks and months. In this case, fire signals on satellite images can be traced back to this kind of land management activities.
In the Prescribed Fire Position Paper of the Forest Protection Bureau by the Division of Forestry in Florida, prescribed fire activity is described as a land management application that is essential to the practice of forestry, management of wildlife, preservation of endangered plant and animal species, improvement of range conditions and reduction of wildfire damage in the wildland/urban interface areas. While there is general public and landowner concern with increased smoke, reduced air quality, and liability; the general public and landowners benefit significantly from the reduction of devastating wildfire, improved wildlife habitat and forage, preservation of endangered and threatened plant and animal species, and improved management of forest resources. The prospect of severe reductions in the utilization of this management tool is of major concern to Florida’s natural resource managers and conservationists due to the subsequent loss of derived public and private benefits. They suggest the need for legislative attention.