Why are forest fires in the hills intensifying this summer?

• Forest fires continue to scorch several hectares of green cover in the Uttarakhand and Himachal Pradesh.
  • Himachal reported close to 750 forest fires, while Uttarakhand recorded over 1,500 such incidents.

• The forest fire season in India lasts between November and June.
• The large forest fires are the most challenging to control due to their intensity, geographical cover and duration that can go up to 5 days.
• Some of the leading natural causes of wildfires include, dry climate, lightning, climate variability and volcanic eruption.
• Uttarakhand had witnessed 51 large fire incidents, the maximum by any Indian state.
• Vulnerability of India’s Forests to Fires:
• As of 2019, about 21.67% (7,12,249 sq km) of the country’s geographical area is identified as forest, according to the India State of Forest Report 2019 (ISFR) released by the Forest Survey of India (FSI), Dehradun.
• Tree cover makes up another 2.89% (95, 027 sq km).
• Based on previous fire incidents and records, forests of the Northeast and central India regions are the most vulnerable areas to forest fires.
• Forests in Assam, Mizoram and Tripura have been identified as ‘extremely prone’ to forest fire.
• States with large forest areas under the ‘very highly prone’ category include Andhra Pradesh, Manipur, Meghalaya, Mizoram, Nagaland, Odisha, Maharashtra, Bihar and Uttar Pradesh.
• As per the 2020-2021 annual report of the MoEFCC, Western Maharashtra, Southern Chhattisgarh and areas of Telangana and Andhra Pradesh, along with central Odisha, are turning into ‘extremely prone’ forest fire hotspots.
• Areas under the ‘highly prone’ and ‘moderately prone’ categories make up about 26.2% of the total forest cover.

What does a forest fire mean?

• A wildfire, forest fire, bushfire, wildland fire or rural fireis an unplanned, uncontrolled fire in an area of combustible vegetation starting in rural and urban areas.
• Some forest ecosystems in their natural state depend on wildfire.
• Depending on the type of vegetation present, a wildfire can also be classified more specifically as a forest fire, brush fire, bushfire (in Australia), desert fire, grass fire, hill fire, peat fire, prairie fire, vegetation fire, or veld fire.

What are the causes of forest fires?

• Several factors like temperatures, precipitation, vegetation, and moisture contribute to the scale and frequency of these fires.
• According to the Forest Survey of India, nearly 36 per cent of India’s forests are prone to frequent fires.
• Higher fire incidents are reported in March, April and May due to ample availability of dry biomass (fuel load) following the end of winter and the on-going summer season.
• Most forest fires, according to experts, are man-made due to changes in agriculture and unchecked land-use patterns.

How are forest fires classified?

Forest fires are broadly categorised into three categories:

• Ground: Fires that burn organic material in the soil are called ground fires, and they burn slowly, under vegetation.
• Surface: Surface fires are caused largely by burning of dry leaves, branches and other materials on the ground. Such fires spread swiftly, as in the case of fires in Himachal.
• Crown fire: Crown fires burn quickly, from one tree top to another and have huge flames with intense heat. Such fires are rare in India.

Has there been an increase in forest fire incidents this year?

• The Forest Survey of India data on forest fire points between March 1 and April 30 this year shows a clear spike in incidents coinciding with rising heat wave conditions.
• The number of forest fire points rose from 8,735 to 42,486 during the four weeks in March.
• However, the week-wise progress in the number of forest fire points in April peaked in the first week fell to 13,719 in the second week and picked up to touch 20,285 in the last week.
• In the last three months, Uttarakhand has recorded at least 1,791 forest fires that have scorched over 2,891 hectares of forest land, including 2,079 hectares of reserve forest areas. These fires have caused estimated damage to property worth over Rs 74 lakh and death of at least one person.
• While the numbers are lesser in last year’s comparison, the issue of forest fires intensifying mainly in mid-February and continuing usually till mid-June is a major problem for the hill state which has forests in almost 71 per cent of its geographical area.
• The chief conservator of forests admitted that the number of forest fires this year increased significantly in the month of April mainly due to unexpected rise in temperature and less rain.
• The strong wind velocity also contributed majorly to spreading the fires fast across the jungles.
  

How vulnerable are forests in Uttarakhand and Himachal?

• Out of the total forest land in Uttarakhand, 26 per cent consists of pine trees. Dry pine leaves are highly inflammable and significantly increase the fuel load. Officials admit that the situation is alarming because the peak time for forest fire – the third week of May when the temperatures are the highest – is yet to come.
• In Himachal, of the 196 forest ranges in Himachal Pradesh, 80 are vulnerable to fires. The chir pine forests which make up 15 percent of Himachal’s forests are most prone to fires. The chir forests are spread over an area of 1258.85 sq km, which is about 3.4 per cent of the total forest area of the state.

How have other places prone to forest fires fared so far?

• Apart from Himachal and Uttarakhand, Assam, Madhya Pradesh, Maharashtra, Tripura, Mizoram and Odisha report frequent forest fires annually.
• Incidentally, Madhya Pradesh, Uttarakhand, Odisha — along with Chhattisgarh and Maharashtra — have been the top five states reporting high number of large forest fires ranging between 143 to 441 between November 2021 and April 2022.

Impacts of forest fires

• Human risk and exposure
• Airborne hazards
• Water pollution
• Post-fire risks
• Health effects: Wildfire smoke contains particulate matter that may have adverse effects upon the human respiratory system.