In the last year, there were the most forest fires in the previous ten years

The summer season is a period of increased risk of forest fires due to high temperatures and drought. Therefore, we should therefore take extra care when staying in nature. In 2022, there were 2,473 forest fires on a total area of approx. 1,715 ha, which is the most in the last 10 years. Forest fires accounted for 12% of all fires in the Czech Republic. In recent years, their share in the total number of fires has been increasing.

The probability of a forest fire is determined by natural conditions, as the drought, wind or even tree bark beetle infestation.

In the long term, natural fires present one quarter of all fires in the Czech Republic. However, their share increased to one third in 2022. The significant increase is due to more than twice the number of fires in March 2022, compared to the number in other months.

More than half of the fires in March started in nature. These fires were mainly caused by severe drought and careless actions of people. Natural fires include fires in agricultural areas, open areas, such as orchards, gardens, meadows, parks, etc. and especially forest fires. In the long term, forest fires present almost a third of natural fires.

The extent of forest fires is on average around 400 ha per year, the resulting damages amount to over 14 million CZK and more than 20 people are injured on average. However, in 2022, the affected area was 1,715 ha. Direct damage amounted to 49.5 million CZK and 63 people were injured. The unique values have been caused by a fire in the Czech Switzerland National Park.

For comparison – in 2021 firefighters extinguished 1,517 forest fires on a total area of approx. 411 ha, in 2020 there were 2,081 forest fires on a total area of approx.484 ha.

Obviously, the most forest fires occur in the Vysočina Region and the Central Bohemian Region. Firefighters extinguish the fewest forest fires in the Prague capital city, the Olomouc, Zlín and Pardubice regions.

Up to 96% of forest fires do not exceed an area of 1 ha, and 93% of forest fires do not require a bigger number of firefighters than from the first stage fire alarm. The most extensive fires tend to occur in low-lying forests or in forests where logging takes place. Such fires account for up to three quarters of the affected area. This is facilitated by rapid spreading through grass, sedge, needles, leaves or peat.

Forest fires can be caused by a natural phenomenon (lightning), but half of the cases are due to human negligence. In such a case, it is most often a matter of disrespecting the ban on starting fires in the forest, their subsequent insufficient extinguishing, or a discarded cigarette butt. Almost the other half of the causes of fires remain unexplained or fall into the category of unproven culpability.

When justifying the causes of forest fires, it is shown every year that they occur most often due to human activity, especially carelessness (in 2022, there were 1,275 fires on a total area of 1,399 ha). By far their highest number and range was recorded when fires were started by people.

Natural influences (lightning) caused fires in 23 cases, while the damage was reported on an area of 1.8 ha.

In 2022, there were a total of 279 fires recorded for unexplained causes on an area of 160 ha (in 2021, there were 136 fires on 204 ha).

Photo: Improperly carried out burning of brush carries a high risk of forest fire (Silesia, Bruntál Region, May 2022), FGMRI (VÚLHM) archive

Forest fires occur mostly often between March and October. Most forest fires usually occur in April, but in 2022 there were exceptionally many in March. According to the time of origin, most fires occur in the afternoon, between two and seven o’clock in the afternoon.

Forest fires are difficult for firefighters to put out, because they usually occur in difficult-to-access and challenging terrain where firefighting equipment cannot be fully utilized. Forest fires are dangerous regarding their ability to spread at high speed. In addition, the progress of a fire in the forest is often unpredictable, and the fire can thus spread, for example, under the surface of the ground in a burrow or through the roots of trees. Then it is very difficult to estimate where new fire outbreaks will appear.

Extinguishing forest fires is very time-consuming and requires the involvement of a large number of firefighting units. A large amount of fire-fighting water is necessary to locate and then extinguish such large-scale fires, which firefighters often have to bring from a great distance, or they must use aerial equipment.

At the turn of July and August 2022, in the period from 24 July to 12 August, the largest forest fire in the modern history of the Czech Republic broke out in the area of northern Bohemia. Approximately 1,060 ha of forest on the territory of the Czech Switzerland National Park (NP) were affected (approximately another 250 ha were affected on the territory of the neighbouring Saxon Switzerland). A significant part of the fire was represented by the area with the occurrence of bark beetle dry trees. The main problem in extinguishing the fire was the inaccessibility of the terrain (steep slopes and ravines) and the initial lack of water for extinguishing.

Table 1: Number of fires in the last 10 years (source: Statistical yearbook for the year 2022 of the General Directorate of the Fire and Rescue Service)

 Table 2: Damage caused by forest fires (source: Statistical yearbook for the year 2022 of the General Directorate of the Fire and Rescue Service)

 The increasing in the number of injured people is caused by the fire in the Czech Switzerland National Park.

Source of information: Statistical yearbook for the year 2022 of the General Directorate of the Fire and Rescue Service (Ministry of the Interior).

Prepared by Ing. Jan Řezáč, VÚLHM, v. v. i., e-mail: rezac@vulhm.cz

Introductory photo: Consequences of a forest fire (Bohemia, Děčín Region, November 2022), FGMRI (VÚLHM) archive