Deforestation – Landuse/Landcover Changes
(Effects on Atmosphere and Climate Change)

 

 

 

Forests are vital for human and animal lives as they are home to millions of species, prevent soil erosion, play a crucial role in water cycle by returning water vapor back into the atmosphere, absorb greenhouse gases that fuel global warming, keep soil moist by blocking the sun, absorb carbon dioxide and produce oxygen.

Deforestation is an important factor in global climate change. It is well known that deforestation is a big problem in the world today, with hundreds and even thousands of vulnerable forest being cut down both for tinder and to make way for arable farmland for cows and other livestock. Not only could this lead to an increase in the rate of deforestation, but also bring about a loss of many different species of plants and animals, resulting in a devastating effect on the climate.

One of the main reasons for this could be the fact that forests are natural ‘carbon sinks’, or areas of natural environment (such as oceans) that can take carbon dioxide from the atmosphere and convert it into oxygen that we and other animals need to keep alive. By cutting down huge areas of forest, therefore, without replacing trees that we remove, we are causing an inadvertent change in the amount of carbon dioxide in the atmosphere, which can have a huge impact on the rest of the world.

Forests cover about 30% of the world’s land area and large patches of forests are lost every year due to deforestation. If the current rate of deforestation continues, there will be no more rainforests in 100 years. It is estimated that due to cutting and burning of forests every year, more than 1.5 billion tons of carbon dioxide is released into the atmosphere

Main Causes of Deforestation

There are many reasons why forests are being cut down all over the world. These are listed below:

Wood and Timber

This reason is obvious, and perhaps, permissible. We need timber and wood to be able to build houses, furniture and other essential things that help us live the lives that we lead today. It is estimated that 500,000 hectares of forest all over the world are cut down every week by the logging industry. This does not include the number of trees that are cut down by illegal loggers. Many of these trees never get replaced.

Farmland

Strangely enough, the biggest threat to forests all over the world is not the need for timber or wood, it is the demand for arable farmland on which farmers can either grow crops or make way for cows to feed the population of the world. It has been suggested that as much as 80 percent of the farmland that was created between 1980 and 2000 came through cutting down of forests. This translates to more than half a million square miles of forest that was destroyed in the space of just twenty years. More and more forests are being cut down as our demand for meat and other foodstuffs creeps higher and higher.

Urbanization

With more people being born every year and the older generations living for longer, there are more people on our planet than ever before. This means that we need more houses to accommodate the increased population, and houses need space. Some of the forest areas that are cut down are destroyed in order to make way for new houses and communities.

Palm Oil

Palm oil is a type of edible vegetable oil that is derived from the palm fruit, grown on the African oil palm tree. Oil palms are originally from Western Africa, but can flourish wherever heat and rainfall are abundant. Palm oil often comes at the expense of forests that are cut down to make way for plantations. Palm oil constitutes over 30% of the world’s vegetable oil production and is an essential ingredient in 40-50% of household products in many developed countries. It is used in a wide variety of products, including baked goods, confectionery, shampoo, cosmetics, cleaning agents, washing detergents and toothpaste. Up to 300 football fields of forest are cleared every HOUR to make room for palm plantations. In the past 10 years, the orangutan population has decreased by 50 percent as the result of habitat loss from forest clearing for palm plantations.

Paper

Until we start making a huge effort to start recycling paper, we are going to continue cutting down forests all around the world at an alarming rate. Paper is still common, even in today’s world packed with technology and paperless machines. We still demand books, toilet paper, kitchen towels and other products that require us to cut down trees.

Mining

Oil and mining companies require large amount of land to build plants. These plants come at a cost of chopping of thousands of plants and trees. Apart from that, roads and highways have to be built to connect cities and these require trees to be cut down that come in the way.

Effects of Deforestation on Climate

With so much deforestation every year, many of the biggest carbon sinks in the world are being shrunk drastically. This means that less of the carbon dioxide in our atmosphere is getting converted back into oxygen by photosynthesis. This is already having a huge impact on our climate. A few of the effects that deforestation can have on the climate at detailed below:

Global Warming

Carbon dioxide is a greenhouse gas, which means that it traps infrared rays from the sun and retains heat in the Earth’s atmosphere. Whilst for the most part this is a good thing, any increase in the atmospheric carbon dioxide above a certain critical level would translate into more heat than required being trapped, raising the average temperature of the earth (otherwise known as global warming) which may trigger a large number of knock-on effects.

Weather Patterns

Water vapor is another greenhouse gas that keeps heat from the sun trapped in the Earth’s atmosphere and helps maintain a temperature at which life can flourish on our planet. Deforestation affects the amount of water vapour in the air. Studies have shown that deforestation has contributed to the amount of water vapor in the air and, over just a few years, the amount of water vapor present has increased by four percent. Besides increasing the temperature of the Earth’s surface and atmosphere, this also has knock-on effects for weather patterns around the globe.

Water Cycle

The water cycle is very important for all species of animals and plants all over the globe. Trees contribute a great deal to the water cycle, and forests are particularly useful for regulating the way that water is recycled back into the atmosphere to come down as rain in places that are otherwise dry. By chopping down hundreds of thousands of trees every year and never replacing them, we are affecting the natural water cycle of the world, which means an increase in the pollution present in the water that now rains down on places all over the world.

Quality of Life

The general quality of life not only for humans but also for other animals that live in, around and even many miles away from forests is gradually getting worse as a direct result of deforestation. Because soil is more often getting washed away by heavy rainfall since it is no longer anchored to tree roots, it is entering the main waterways of the world. Lakes, rivers, streams and even the sea are getting contaminated with soil that has been washed into them. This means that creatures in rivers and sea are in danger and also that any animals that drink from these water sources regularly could be in danger of getting poisoned.

Ocean Acidification

Besides causing problems in the waterways because of an increase in soil and pesticides, for instance, deforestation has also been directly linked to ocean acidification, or a decrease in the average pH of the oceans. Oceans become more acidic when more carbon dioxide is present. Because so much more carbon dioxide is now present in our air, not only because fewer trees are converting it into oxygen, but also because the processes involved in deforestation cause a lot of fossil fuels to be burned, it is gradually seeping into the oceans, lowering the average pH and killing off many species of plant and animal life.

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