Wildfire acreage, two dimenional or three?

Asked by: Amy Eveland

How are wildfires size measured?

(KGO) — Wildfires are typically described in terms of the number of acres burned. Mathematically, an acre is equal to 43,560 square feet. That’s approximately the size of a football field, minus the end zones. For comparison, the City of San Francisco, at 46.87 square miles, is nearly 30,000 acres.

What is the average size of a wildfire?

There are variations in the number of acres burned from year to year roughly in five to six-year cycles, but in the late 1980s the average size of a wildfire in the U.S. was 30 acres. That number has increased every decade since, bringing the average for this decade (to date) up to 101 acres.

How do you calculate wildfire containment?

Containment is normally expressed as a percentage of the entire perimeter (the percentage of the black “contained” perimeter compared to the entire perimeter). A wildfire with 25% containment means control lines have been completed around 25% of the fire’s perimeter.

What makes a wildfire complex?

Complex fire



When there are two or more wildfires burning close together in the same area, they are often called a “complex” and attacked by firefighters under a unified command. In the summer of 2020, a siege of dry lightning strikes sparked about 40 fires in three national forests in northwestern California.

How many acres is a large wildfire?

Class E – 300 acres or more, but less than 1,000 acres; Class F – 1,000 acres or more, but less than 5,000 acres; Class G – 5,000 acres or more.

How many acres is considered a large fire?

A Large Fire as defined by the National Wildland Coordinating Group, is any wildland fire in timber 100 acres or greater, and 300 acres or greater in grasslands/rangelands, or has an Incident Management Team assigned to it.

How do fire containment lines work?

When indirect containment lines are built, firefighters need to reduce the fuel near the line to moderate the fire activity. Indirect containment lines are built some distance away from the active fire edge to take advantage of existing barriers and to provide for firefighter safety.

What does fire perimeter mean?

The perimeter is the distance around the fire or along the handline. Perimeter is determined by adding the lengths of the various lines that enclose the black area of a fire.

How do firefighters make containment lines?

Quote from video: Build their main product a fire line a physical line cut in the earth cleared of things that can burn they cut the line with bulldozers.

How are wildfires measured and classified?

Wildfires are classified as burning at different levels of severity: low, medium, and high. Severity is a function of intensity, or how hot the fire was, and its spread rate, or the speed at which it travels. A high-severity fire is going to do some real damage.

What was the largest wildfire in history?

The Chinchaga Fire started in logging slash in British Columbia, Canada, on 1 June 1950 that grew out of control and ended five months later on 31 October in Alberta; in that time, it burned approximately 1.2 million hectares (3 million acres) of boreal forest.

What is the largest wildfire in US history?

1. The 2021 Dixie Fire, California. Following an unprecedented heat wave in June 2021, California was once again engulfed in raging wildfires. According to CalFire, the fire has burned more than 463,000 acres in Northern California, taking hundreds of buildings down with it and threatening nearly 14,000 structures.

What is the largest wildfire in history?

Top 12 Largest Wildfires in History:

• 2003 Siberian Taiga Fires (Russia) – 55 Million Acres. …
• 1919/2020 Australian Bushfires (Australia) – 42 Million Acres. …
• 2014 Northwest Territories Fires (Canada) – 8.5 Million Acres. …
• 2004 Alaska Fire Season (US) – 6.6 Million Acres. …
• 1939 Black Friday Bushfire (Australia) – 5 Million Acres.

What is the largest wildfire in US history?

1. The 2021 Dixie Fire, California. Following an unprecedented heat wave in June 2021, California was once again engulfed in raging wildfires. According to CalFire, the fire has burned more than 463,000 acres in Northern California, taking hundreds of buildings down with it and threatening nearly 14,000 structures.

How big is Australia wildfire?

The major fires peaked during December–January. As of , the fires burnt an estimated 14.3 million hectares (35 million acres; 143,000 square kilometres; 55,000 square miles), destroyed over 3,000 buildings (including 2,779 homes) and killed at least 34 people.

What is the most famous wildfire?

The 10 Deadliest Wildfires in History (at a glance)

• PESHTIGO FIRE (1871) 1,500 fatalities.
• GREAT MICHIGAN FIRE (1871) 482 fatalities.
• CLOQUET FIRE (1918) 453 fatalities.
• GREAT HINCKLEY FIRE (1894) 418 fatalities.
• GREAT CHICAGO FIRE (1871) …
• THUMB FIRE (1881) …
• INDONESIAN FOREST FIRES (1997-1998) …
• BLACK DRAGON FIRE (1987)

What country has the worst wildfires?

List of largest fires of the 21st century

What country has the most wildfires?

Throughout 2021, Brazil reported approximately 184 thousand wildfire outbreaks, by far the highest figure in South America.



Number of wildfires in South America in 2021, by country or territory.