Why are there Fires in the Amazon Rainforest?
Amazon Rainforest, also known as Amazonia, is the largest tropical rainforest in the world. It is an incredibly large ecosystem in South America, where nature is at once wild and mysterious. The famous Amazon River, the second longest river in the world, meanders through the dense foliage of this diversity, which boasts a mindboggling variety of plants, insects and wildlife. Often regarded as ‘The Lungs of the Earth,’ the Amazon Rainforest is believed to produce more than 20% of the world’s oxygen. Owing to its importance in the world’s ecological system, National Institute for Space Research (known as INPE) in Brazil, began tracking forest fires in the Amazon Rainforest in 2013.
For this reason, the data released recently by the INPE caused alarm bells to ring around the world when it emerged that there have been 72,843 fires in Brazil between January and August 2019, with more than 50% occurring in the Amazon region. That’s more than an 80% increase compared with the entire 2018, and the highest number since 2013. The northern Brazilian state of Roraima got engulfed in black smoke, while Sao Paolo city located thousands of miles away witnessed an hour-long blackout. Further, the state of Amazonas was forced to declare an emergency due to the forest fires.
What Areas Does Amazon Rainforest Cover?
The Amazon Rainforest extends over 9 countries of the South American continent. A major part, almost 60% of the Amazon Rainforest, is spread across northwestern parts of Brazil. In addition, the whole of Peru and southern Colombia share less than 25% of the area between them. The other countries where the territory of the Amazon Rainforest extends are Bolivia in the south, Ecuador to its east, Venezuela, Guyana, Suriname, and French Guiana to the north.
What is the History of Amazon Rainforest?
Recent studies seem to contradict the earlier claim that the Amazon Rainforest has been in existence for around 55 million years. Rather, research reveals that much of the present area was grassland about 2000 years ago. A gradual transition to wetter climate may have led to the formation of the rainforests over time.
The Stone-age people were arguably the earliest inhabitants of the Amazon Basin, which has been continuously inhabited for at least 10,000 years. Europeans were the first to explore the Amazon in the 16th century. Notably, during the 17th and 18th centuries, Portuguese explorers had penetrated deep into the rainforest in the pursuit of gold but discovered the Amazon River Basin instead.
Amazon Rainforest in Brazil
The country of Brazil lies in the Tropical zone and Temperate zone. The types of forest in Brazil are rainforest, deciduous forest and savannas. The total land area of Brazil is 8,515,767 sq. km (3,287,956 sq. mi), whereas the land area under forest cover is 4,776,979 sq. km (18,44,402 sq. miles) i.e., 56.10% of total land area. A large part of Brazil’s forest cover falls in the Amazon Basin.
Why Amazon Forest Fires Cause Alarm?
It is now widely acknowledged by the scientists that in many regions of the world, the climate system is nearing a tipping point. A tipping point refers to a threshold in the climate system that, when surpassed, can lead to large and adverse changes in the state of the system. In the case of Amazon Rainforest, deforestation may trigger a major tipping point. Studies of rainforests reveal that such forests tend to recycle a substantial part of their rainfall. Hence, destruction of trees in even one part of the forest may lead to droughts or deficient rainfall in other parts of Brazil and even other countries of South America. If the climate system is not restored to its normal state, it will continue to pass into a hothouse state, which may lead to further fresh water and food shortages, and uninhabitable conditions for the human populations.
What Factors Cause Forest Fires?
Forest fires pose a serious threat to the flora and fauna and disrupt the biodiversity and the natural habitat of the region. It has been observed that forest fires are so extreme that they burn at a temperature above 2,000 degrees Fahrenheit, which means it is hot as equal to the Venus surface. When a forest catches fire, the flames have the capacity to reach 50 meters high and change the weather pattern of the surrounding area to a great extent.
- Fire triangle
Wildfires are caused due to human intervention or at times naturally as well. And the fire spreads fast due to the presence of three elements such as oxygen, heat and fuel which foresters have termed as the ‘fire triangle’.
- Lack of rain in the dry season
Brazil is a large country, which can be divided into three main climatic regions: Equatorial, with rains throughout the year, in the Amazon Basin plus a small coastal area; Tropical with a dry season in the vast central area, plus a small northern portion; Mediterranean, with temperate winters and hot summers, in the extreme south. A large area of Amazon rainforest falls in northern Brazil (equatorial climate), which remains hot and humid throughout the year, and experiences constant rainfall, including heavy showers and thunderstorms. However, the rainfall is more abundant from December to May. In most of central and southern Brazil, there is a dry season (generally from May to August) and a rainy season (usually from October to March, with highest rainfall between December and February).
- Natural causes
There are two prime natural causes of forest fire; lightning and volcanic eruption. Researchers say due to lightning, a large number of wildfires spark off. Sometimes, lightning strikes trees, rocks, power cables and other such material, which stirs up the fire. Apart from lightning, volcanic eruption is another natural cause of wildfire. In this case, hot magma in the earth’s crust is thrust out as lava and gushes through the forest field, igniting a forest fire.
- Human causes
It is believed that 90% of bushfires are caused by humans. It goes without saying that human beings have a habit of occupying space everywhere possible. And they do not even spare the forests. Besides, forest fires are deliberately started for deforestation activities to exploit the forest for timber, charcoal, establishment of farmlands and cattle ranches, plantations and highway projects.
In the case of Amazon Rainforest fires, many activists and research agencies are attributing it to human causes rather than the dry season. These activists have pointed to the accelerated rate of deforestation in the Amazon Rainforest lying in Brazil, with fires being started to clear the land spiraling out of control and engulfing large areas.
How Forest Fires Can be Extinguished?
Forests fires cannot easily be extinguished or subdued. It is essential to fight the ‘fire triangle’ of oxygen, heat and fuel. To reduce oxygen, fog nozzle can be used with foam. Fog helps in dousing the flaming gases by filling the space with millions of slitted particles of water. And this smothering can be practiced from helicopter or any other wing aircraft. Heat can be tackled by cooling it with water, foam or by spattering the available fuels in order to reduce the effect. Now to reduce the third element of the triangle i.e. fuel, it is required to remove underbrush from the path of the fire in order to prevent the fire from spreading beyond the control line. And this is mostly done by constructing a controlled blaze towards the main fire, on the inside of the control line. Firefighters then strive to burn up all the underbrush that lies between the fire and the control line to prevent outward spread.
For bigger fires, authorities may use helicopters and planes that can spray substantial quantities of water, mixed with fire retardant, over a larger area. On the other hand, natural rain can be a boon in fighting a raging forest fire, though dry season may have the opposite effect.
In conclusion, forest fires spread quickly, and are difficult to control or extinguish easily. Therefore, it is important to keep the human greed in check and prevent any activity which can lead to a blaze in or around a forest, especially in case of diversified and dynamic ecosystem such as the Amazon Rainforest.
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