Our planet is unique in its ability to support life. However, within the limitations of our understanding of the terms evolution and progress, we humans have contributed to a number of disastrous climate change triggers. Some of them are:
Increased carbon dioxide emissions.
Increase in greenhouse gas levels.
Increase in land, water and air pollution levels.
Climate change refers to a long-term change in the average weather patterns over a specific region, over a significant period of time. The abnormal variations cause subsequent effects on the Earth's atmosphere and significant regions like the polar ice caps and the natural habitat of different life forms. The various causes of climate change are identified and measured with the help of environmental policies that keep periodical track of environmental damage and the shift in any or all of the dynamic Earth processes. The triggers are all interrelated human activities as well as external factors, and collectively take a toll on 'climate forcing'. In climate science, climate forcing relates to the change in net irradiance, calculated at tropopause.
Causes of Climate Change
The effect of climate change on the planet and various life forms that inhabit it manifests over an extended period of time. The internal variability is recognized in the form of hysteresis. In this measure, the climate change recorded does not correlate or correspond to planned input. However, climate change is not only the cause of rapid deterioration of our environment, but is also irreversible. Some of the major causes of climate change are:
Solar variation
There are a number of variations in solar activity that have been observed through the study of sunspots and beryllium isotopes. The sun provides the Earth with heat energy, an integral part of our climate. Solar variation has triggered a phenomenon called global warming.
Orbital variation
The elliptical path taken by the Earth around the sun plays a significant role in the distribution and amount of sunlight that reaches the Earth's surface. These Milankovitch cycles have a direct impact on glacial activity. The eccentricity, precession and axial tilt of the Earth, along the elliptical path, creates changes in seasons.
Plate tectonics
The landmass on the planet is made up of plate tectonics that shift, rub against one another and even drift apart. This results in the repositioning of continents, wear and tear of the mountains, large-scale carbon storage and increased glaciation.
Volcanic action
In the course of volcanism, material from the Earth's core and mantle is brought to the surface, as a result of the heat and pressure generated within. Phenomenon like volcanic eruptions and geysers release particulates into the Earth's atmosphere, that affect climate.
Thermohaline circulation
Climate changes also result from the atmosphere-ocean relationship. Climate fluctuations such as the El Niño Southern oscillation and the Arctic oscillation act as heat reservoirs within the oceans. Thermohaline circulation refers to the redistribution of heat via slow and deep oceanic
current.
There are a number of anthropogenic factors that are responsible for change in the Earth's environment. The result of human influence on the climate is not only direct, but also unambiguous.
The Industrial Revolution in the 19th century saw the large-scale use of fossil fuels for industrial activities. Fossil fuels such as oil, coal and natural gas supply most of the energy needed to run vehicles, generate electricity for industries and households. The energy sector is responsible for about ¾ of the carbon dioxide emissions, 1/5 of the methane emissions and a large quantity of nitrous oxide.
Carbon dioxide is undoubtedly, the most important greenhouse gas in the atmosphere. Changes in land use pattern, deforestation, land clearing, agriculture, and other activities have all led to a rise in the emission of carbon dioxide. Methane is another important greenhouse gas in the atmosphere. It is released from animals such as dairy cows, goats, pigs, buffaloes, camels, horses and sheep Methane is also emitted during the process of oil drilling, coal mining, leaking gas pipelines, landfills and waste dumps.
Agriculture as a Contributor to the Causes of Climate Change
According to the Intergovernmental Panel on Climate Change, the three main causes of the increase in greenhouse gases observed over the past 250 years have been fossil fuels, land use, and agriculture.
Agriculture has been shown to produce significant effects on climate change, primarily through the production and release of greenhouse gases such as carbon dioxide, methane, and nitrous oxide.
Another contributing cause of climate change is when agriculture alters the Earth's land cover, which can change its ability to absorb or reflect heat and light. Land use change such as deforestation and desertification, together with use of fossil fuels, are the major anthropogenic sources of carbon dioxide.
Deforestation as a contributor to the Causes of Climate change
It is important, first to understand what a precious resource rainforests play in our world. They form part of a delicate ecosystem that has taken millions of years to evolve.
Rainforests every year help to absorb almost 20% of man made CO2 emissions therefore deforestation can be classed as a major contributor to the causes of climate change. Cutting down rainforests faster than they can be replaced has a devastating effect on the carbon emission cycle producing an extra 17% of greenhouse gases. Remember trees absorb CO2. More deforestation means more CO2 build up in the atmosphere.
Deforestation by means of cutting down and burning these tropical rainforests usually pave the way for agriculture and industry which often produce even more CO2.
Forests reduce greenhouse gas emissions to combat global warming. 20% of global greenhouse gas emissions result from deforestation and degradation of forest, more than all the world's cars, trucks, ships and planes combined. Fossil fuels release carbon dioxide into the atmosphere contributing to global warming and climate change. Forest alleviates this change by converting carbon dioxide to carbon during photosynthesis. The world's forests contain about 125 percent of the carbon found in the atmosphere. This carbon is stored in the form of wood and vegetation through "carbon sequestration".
Trees possess about 20 percent carbon by weight and biomass of forest acts as a "carbon sink." The soil organic matter produced by the decomposition of dead plant material also acts as a carbon store. Consequently forests store enormous amount of carbon: in total, the world's forests and forest soils currently store more than one trillion tons of carbon, twice the amount found floating free in the atmosphere, according to FAO studies.
The atmospheric carbon dioxide concentration in the pre-industrial era was 280 ppm. Right now the level has risen to 375 ppm, a 30% increase. It is predicted that the level will be 450 ppm in 2050 resulting in 1.8-3ºC increase in temperature eventually. Therefore, global warming will produce a sharp upswing followed by a deep plunge into a glacial period several thousands years from now. A myriad of potential impacts such as increased cyclone intensity; melting of polar iceberg and glaciers; increased salinity and changes in oceanic currents sea level rise and inundation of low lying cities like Venice, Cairo, New Orleans, Lagos, Amsterdam, etc.; coral bleaching and mortality of coral reef; colonization of invasive species and species migration; changes in ecosystem; mass extinction; ozone layer depletion; water shortage; and spreading of diseases -- is predicted. "
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