By Parul Srivastava on 05 June 2019.
During the period 5 Jun 2018–4 Jun 2019, as per the database of Global forest Watch there were 58,620 fire alerts in India and 2,180,652 fire alerts across the globe.
Forest fire threatens the precious forest resources and biodiversity and is one of the important causes for the damage of forest wealth and air quality of the forest. According to Forest Survey of India, incidents of the forest fire in the country shot up by 49.32% in the past three years (in 2016 a total of 24,817 forest fire incidents, which increased to 35,888 in 2017 and 37,059 in 2018) during summer. Studies suggest that 90% of vegetation fires in India are man-made and, annually, about 3.73 million ha. of forest area is affected, leading to a loss of US$104 million. At the same time, fire is also a significant and periodic factor in the ecology of many boreal forests but plays a vital role in deforestation in tropical and subtropical regions. Early detection and suppression of forest fire is crucial to minimizing the destruction that the fires may cause. Forest fire releases pollutants like smoke, sulphur dioxide, nitrogen dioxide, ozone, particulate matter, and carbon monoxide into the atmosphere that will continue to warm the planet well into the future. The subsequent increase in the carbon dioxide levels in the atmosphere, contribute to the greenhouse effect and climate change.
According to an estimate (International Energy Agency, 2018), wildfires emit 8 billion tons of CO2 per year globally for the past 20 years and reached to 32.5 billion tons in 2017. However, all the wood carbon is not emitted as CO2 due to incomplete combustion, which, on the other hand, results in the formation of CO. The emission also depends on the type of vegetation being burned. For example, the burning of resinous pine forests creates dangerous soot. Increased emission of the noxious gases not only pollutes the atmosphere but also increases the temperature of the surroundings, thus adding in climate change too. As the effects of climate change are already visible, changes in average temperature and rainfall pattern may also seriously affect the occurrences and intensities of forest fire. The changing climate has another significant repercussion on the transfer of air pollutants emitting from forest fire. There is a possibility of the long–range transfer of various air pollutants such as aerosols, carbon monoxide, particulates etc. during certain atmospheric circulation conditions. The other adverse effect of forest fires is the water vapor that results from the fire gets condensed onto fine atmospheric particles, which increases the haze formation resulting in reduced visibility. Aerosols emitting during the forest fire can also act as active cloud condensation nuclei, which further affect the precipitation and related weather event.
Moreover, the burning of biomass also results in the emission of methyl bromide, which is a potential ozone-depleting substance. Besides, diminishing forest resources are severely affected by the regular occurrences of forest fire. The irregular precipitation patterns, and altering moisture levels due to the warming, has resulted in more dryness in already dried areas. Overall the warmer temperature increases evapotranspiration, because of which atmosphere pulls more moisture from the soil, making the soil drier. This dryness acts as one of the pre-requisite for the inception of fire. Dryness and high-temperature conditions not only result in frequent fire; rather, these also aggravate the duration and severity of the fire resulting in the increase in overall pollution load into the atmosphere. Therefore, more efforts in this direction need to be made to combat the adverse effect of climate change that in turn, would help reduce risks of fire.
Parul Srivastava, PhD, is a member of the IUCN Commission on Ecosystem Management 2017-2020. Parul is the Head of RS & GIS, IORA Ecological Solutions, New Delhi, India.