Climate Change: Deforestation

Forests cover 31 percent of the global land area. Approximately half the forest area is relatively intact, and more than one-third is primary forest (i.e. naturally regenerated forests of native species, where there are no visible indications of human activities and the ecological processes are not significantly disturbed).

More than half of the world’s forests are found in only five countries (the Russian Federation, Brazil, Canada, the United States of America and China) and two-thirds (66 percent) of forests are found in ten countries. Here is a global view of forests:

Global distribution of forests showing the ten countries with the largest forest area, 2020 (Million Hectares of World’s Forest)

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Source: FAO
Prepared By: Dr. Mir F. Ali

The total forest area is 4.06 billion hectares, or approximately 5 000m2 (or 50 x 100m) per person, but forests are not equally distributed around the globe.

Forests play a critical role in the Earth’s climate system, in a number of different ways. Most importantly for global climate change, they capture carbon dioxide (CO2) from the atmosphere and convert it, through photosynthesis, into living biomass: Tree Trunks; Roots; Branches; and Leaves.


Forests also store carbon in forest soils, absorbed through leaf litter, woody debris and roots; whether these inputs are sequestered in the soil matrix or biodegraded and returned to the atmosphere as CO2, and if so at what rate, depends on complex interactions involving soil minerals, plants and soil organisms, and organic components, all influenced by factors such as local climatic conditions and forest management.


Forests also play a role in mitigating climate change by:

  • Absorbing the CO2 emitted into the atmosphere from human activities, chiefly the burning of fossil fuels for energy and other purposes, into the terrestrial carbon sink;
  • It has been estimated that since 1750, forests (and other vegetation, but mainly forests) have been responsible for about half of the carbon emissions naturally sequestered from the atmosphere; the rest has been absorbed by the oceans; and
  • Together, forests and oceans form a natural buffer against climate change (though increasing concentrations of CO2 in seawater gradually acidify the oceans, with negative impacts on marine life).

The fact of the matter is that as the largest storehouse of carbon after the oceans, forests already absorb and store about 30 per cent of current levels of carbon emissions from fossil fuels and industry into their biomass, soils and wood products, and have the potential to store much more.

Here is a great surprise:

Source: BBC
  • Scientists have discovered a huge pool of carbon in a central African peat swamp that nobody knew about before;
  • The Cuvette Centrale peatlands in the central Congo basin is believed to be the world’s largest peatland system, and the region’s most important carbon sink. Carbon sinks are forests, oceans, or other natural locations that have the ability to absorb carbon from the atmosphere;
  • The peat contains slowly decaying plants, or vegetation, that have been accumulating for over 10,000 years. The vegetation is a natural storehouse of carbon, which it takes in from the atmosphere. This particular peatland stores about 30 billion metric tons of carbona almost equal to 20 years’ worth of U.S. fossil fuel emissions; and
  • In order to map out this peatland, satellites were used to take pictures and determine the area of the peat, which is 55,000 square miles.

The question is: What else forests do to help humans?

Here is what forests and especially tropical forests do to provide a lot of value to humans among other things, they:

  • Regulate and filter water;
  • Clean the air;
  • Moderate water flow;
  • Improve agricultural conditions like soil quality; and
  • Help mitigate or prevent natural disasters like erosion and landslides

These are called ecosystem services. Some of them, like flood control or supporting agriculture, may even be worth actual money. Here’s an example:

  • Crops bring in income. If the ecosystem is helping farmers to grow more crops, that’s worth money, too.

Forests are biologically diverse systems, representing some of the richest biological areas on Earth. They offer a variety of habitats for plants, animals and micro-organisms. However, forest biodiversity is increasingly threatened as a result of deforestation, fragmentation, climate change and other stressors.


Meanwhile, tropical rainforests – like the Amazonian one – play a crucial role in the water cycle. With no forests, the precipitations in the region decrease drastically. Researchers also estimate rainforests have provided us with over half of anti-cancer plants they have identified so far. More than 80 percent of land-dwelling species depend on forests as their natural habitats. The biodiversity of these ecosystems also ensures global food security.

Here is the problem. When forests are destroyed, they release large quantities of carbon dioxide (CO2)  into the atmosphere, which contributes to climate change. At present, however, about 12 per cent of global greenhouse gas (GHG) emissions are estimated to derive from deforestation, a process which is it made more acute by the impacts of climate change. Forests can also help communities adapt to the impacts of climate change, stabilizing and cooling local climates, including water flow and rainfall.


Everybody knows that burning of oil and gas and the release of pollutants like – CO2, lead, nitrogen, ground-level ozone, particle pollution, and sulfur oxides are responsible for global warming. What they may not know that deforestation is one of the major causes for global warming.  Consequently, deforestation is considered to be the main reason for the rise in the level of greenhouse gases in the atmosphere.

Normal scene in the Amazon

Here are some facts about deforestation:

  • Deforestation affects the people and animals where trees are cut, as well as the wider world. Some 250 million people living in forest and savannah areas depend on them for subsistence and income—many of them among the world’s rural poor;
  • Eighty percent of Earth’s land animals and plants live in forests, and deforestation threatens species including the orangutanSumatran tiger, and many species of birds; and
  • According to the most recent reports, the equivalent of around 36 football fields of forests are chopped down, burned, and generally destroyed every minute. And the more forest clearings is created, the more flora and fauna is lost. About 135 species of animals, plants, and insects suffer every day because of deforestation.

Deforestation is the result of decisions made to support the idea that it’s worth more to convert forest land to other uses than to keep the forest standing.


Deforestation is defined as the clearing or thinning of forests by humans. Deforestation represents one of the largest issues in global land use. Estimates of deforestation traditionally are based on the area of forest cleared for human use, including removal of the trees for wood products and for croplands and grazing lands. In the practice of clear-cutting, all the trees are removed from the land, which completely destroys the forest. In some cases, however, even partial logging and accidental fires thin out the trees enough to change the forest structure dramatically.


Here is how Duncan Brack characterized deforestation in his report, Background Analytical Study (Forests and Climate Change), published in March 2019:

  • Deforestation contributes to climate change. When forests are burned or cleared for uses such as cropland, pasture, infrastructure or urbanization, the net flow of carbon from the atmosphere into the forest ends, both in the present and for the entire projected future lifetime of the trees;
  • Deforestation also causes the release of the stock of carbon that has accumulated, both in the trees themselves and in the forest soil;
  • The speed of release of the carbon depends on how the forest is cleared and what the wood is used for: clearance by burning or for use as bioenergy causes an immediate, or almost immediate, release of carbon into the atmosphere, whereas harvesting for wood products, such as timber for construction, panels, furniture or paper, will trap some of the carbon in the product for its lifetime, which ranges from a few years for paper to, potentially, many decades for other wood products; and
  • Forest biomass left in the forest, such as twigs, branches or stumps left after harvesting, will decay and eventually release its stored carbon into the atmosphere; this process can take years or decades, depending on the type of residue and the local climatic conditions (hot or cold, wet or dry, etc.).

Here are five causes of deforestation:

Commercial Agriculture
  • Commercial Agriculture: Converting forests into agricultural land is a disruptive human practice and one of the major causes of deforestation. The global demand for commodities like soybeans and palm oil is pushing industrial-level producers to chop down trees at an accelerating rate. Commercial agriculture accounts for 68 percent of forest loss in Latin America and more than 40 percent around the world. As the largest driver of deforestation, industrial agriculture clears forests to make room for pasture, cropland, and tree plantation;
Forest Fires
  • Forest Fires: While forest fires rarely cause permanent deforestation, they become a serious problem when they occur too often. Not only do they release huge amounts of greenhouse gases, but the resulting clouds of soot also fracture the normal rainfall patterns. Researchers from the U.S., Japan, the Netherlands, Indonesia and Norway published in 2012 an analysis of the causes of deforestation in 100 countries. Their estimates showed uncontrolled forest fires were responsible for about 9 percent of total forest degradation from 2000 to 2010;
Unsustainable Logging
Source: Kaieteur News
  • Unsustainable Logging: Unsustainable logging is the reason behind 70 percent of deforestation in Asia and Latin America. Whereas selective logging that takes place with well-regulated practices does not trigger deforestation. Indonesia is a world-renowned exporter of timber; almost 80 percent of their timber is exported illegally. Estimations state that organized crime gains as much as $10-15 billion dollars from illegal logging annually;
Source: Financial Tribune
  • Mining: Rising demand of and higher mineral prices have increased the impact of mining on tropical forests. Mining projects often require major infrastructure construction, including railway lines, roads, and power stations. They only add to the pressure on forests and freshwater ecosystems in the region. Many forested areas around the glove are rich in minerals. Therefore, they are increasingly vulnerable to deforestation practices. Mining is to blame for about 7 percent of deforestation in developing countries; and
Infrastructure Building
Source: PRWeb
  • Infrastructure Building: Roads, highways, and other infrastructure projects are another cause of deforestation. Linked to around 10 percent of total deforestation in developing nations, road construction provides an entryway to otherwise remote areas. For example, the 5,404-km Interoceanic Highway – from Brazil to Peru – is a priority for conservationists. The plan is to cut a pathway through the biodiverse Amazonian rainforest. Other road expansions in the world also contribute to illegal logging, where companies cut down trees without obtaining permission from local authorities.

Not all deforestation is intentional. Some is caused by a combination of human and natural factors like wildfires and overgrazing, which may prevent the growth of young trees.

The reality is that economic incentives and industrial agriculture can cause large-scale deforestation, even against the wishes of local communities.  However, there is a need to recognize the fact that sometimes there is no choice.  For instance, communities often cut trees down for charcoal because they have no other source of fuel. Or, they may only be able to earn money from informal mining, illegal logging, or another activity that destroys forests.

EDW769 A deforested spot in a mangrove forest
Source: carbonbrief

People that live near forests are also often farmers. Subsistence farmers grow food crops for daily life. And small-scale commercial farmers produce commodities for export and trade.  Unfortunately, their lands are often bad for farming. Soils are poor, conditions are harsh, and crops don’t grow well. This means yields are low. And that means locals can’t grow enough food, earn enough money to support themselves – or both.


It’s true that technology and training could help solve many of these problems. But rural farmers usually don’t have access to them. And then, because their yields stay low, their only option is to clear more and more forest so they can farm on a larger area. 

Here is another reality: Deforestation may help to improve the short-term situation – farmers can at least grow enough food for themselves. But in the long term, it leads to land degradation – meaning farmers need more land again. That creates a vicious cycle of more and more deforestation and degradation. And to make matters worse, chopping down forests for short-term benefits means we’re losing everything else that forests do.

Kanata, Ontario, Canada 20 July 2020