Net Mole: Forest Fires.

Photo credit: US Forest service.

Types Of Forestfire.

1) Crawling fire: The fire spreads via low level vegetation in the forest. It occurs by the slow combustion of surface fuels. Surface fuels are fuel sources that are on the ground, these can be small bushes, logs, tree stumps and fallen leaves and branches. Crawling or surface fires tend to burn without generating a lot of flame. They can spread slowly and steadily and last for days after the main burning event has occurred.
2) Crown fire: A fire that "crowns" that is, it spreads to the top branches of the trees. It can spread at a remarkable rate through the canopy of a forest. Crown fires burn from aerial fuels, these are fuel sources that are at least 1 meter above the ground. Surface fuels can include branches, leaves, tall bushes and bark still on the tree. Crown fires are the most dangerous type of fire as they can spread faster than they can be outrun, particularly on windy days.
3) Jumping or Spotting fire: In a jumping fire burning branches or leaves are carried by the wind and start distant fires, the fire can jump natural fire breaks like roads and rivers.

Reporters Drive Through Butte County Forest Fire With Fire Crew.

firefighters at the unita national forest fire

Photo credit: US Forest service.

Fire Suppression

The typical makeup of a forest fire fighting unit will be a large crew of around 20 firefighters, these crews fight the fire directly and construct fire breaks to help stem the spread of the fire. Other firefighters are grouped around this main unit in rapid response teams. If the fire is extremely remote, firefighters known as smoke jumpers are deployed. These fast attack teams are helicoptered into fires in hard to reach areas as a preemptive strike force. They often working on almost sheer cliffs or difficult terrain, they douse small fires and construct firebreaks.

Photo credit: US Forest service.

Fire authorities in areas prone to wild fires often possess helicopters and fixed wing aircraft specially equipped for use in dousing areas that are inaccessible to ground crews, they can deliver large quantities of water or flame retardant chemicals directly onto the fire site.

In the case of fires that are too large to tackle directly, firefighters control the fire by controlling the area to which it can spread. They do this by creating control lines or extended fire breaks. These control lines can be produced by physically removing any fuel source from in front of the fire, or by backfiring. Backfiring involves starting a small, low-intensity fire, to burn off all the flammable material, in the path of the fire. These are then extinguished by firefighters or, directed in such a way that they meet the main fire front, at which point both fires run out of flammable material and are extinguished.

An indication of the skill and dedication employed by professional fire fighting teams can be seen in the fact that in 2004 US firefighters contained more than 99% of all new wildfires during initial suppressive actions.

Tornado in a Forest fire in Vatreni Croatia.

The powerful updrafts caused by a large wildfire will draw in air from surrounding areas. These self-generated winds can lead to a phenomenon known as a firestorm.