Climate Change Nightmares

The Earth's climate has changed over the years and these changes have been influenced by various factors.These factors are classified into two groups: "anthropogenic" (which is human-induced) and natural. Climate change has been observed since the beginning of the 20th century by scientists who have stated that this change can no longer be attributed to natural influences alone. One factor of the changing climate that has gotten considerable attention is global warming, and this occurrence has been happening faster than anyone could have ever predicted. The problem with this change is that it has been created by humans. Therefore, it's important that humans determine how they are contributing to this change and what they can do to minimize their negative effects.

The following segments look at some of the main influences of natural and human climate change and the effects that they are having on the Earth.

The Greenhouse Effect

Natural Effect

As everyone knows, the Earth has a greenhouse effect, which is a natural occurrence attributed to certain types of gases (these are known as greenhouse gases) which are found within the Earth's atmosphere.What these gases do is allow the sunlight to penetrate, but they also consume heat radiation. Therefore, by doing this the heat absorbed by the gases keeps the temperature of the Earth's surface at around 14oC. If the Earth did not have the natural greenhouse effect, then the Earth's surface temperature would be -19oC or thereabouts.

Human Effect

The industrial revolution was created by humans and in doing sothe greenhouse gases in the Earth's atmosphere were increased by a considerable amount. These increases in gases lead to the atmosphere retaining more heat, which directly leads to surface temperatures increasing globally. This temperature change became known as global warming. Other effects have also been attributed to this increase in temperature which has caused the climate system to change. Together the natural and human affects are called anthropogenic climate change.

So what are the main greenhouse gases and what should we know about them?

• Carbon Dioxide - CO2 is only a tiny part of the Earth's atmosphere, but it is also an extremely important GHG. CO2 is naturally released into the atmosphere via volcanic eruptions and respiration from animals, but unfortunately activities by humans also release this gas, such as the burning of fossil fuels which are used for energy and the human need for deforestation. The problem with CO2 is that it remains in the atmosphere for a very long time, so its impact has been increasing ever since the industrial revolution.
• Water Vapour - This GHG is the most abundant of all the greenhouse gases; however, due to its time in the atmosphere being very short-lived, the impact that humans have on it is very little.Therefore, it is not considered to be a very important GHG .
• Methane - This GHG is considered the second most important gas which is produced by human and natural activities. Organic matter and the decomposition of it is the most indicative source of methane.Examples of this are agriculture and landfills. Methane also comes from ruminants (goats, cows, etc) and their digestion. Although methane is stronger than CO2, this GHG is less exuberant in the atmosphere, but it does absorb much more heat.
• Nitrous Oxide - This greenhouse gas is heavily produced and is very powerful; the sector of agriculture creates this gas through organic fertilizers and their production. This gas is also being produced when fossil fuels are burnt.
• Chlorofluorocarbons - These compounds are man-made and are better known as CFCs.They were created for industrial use and were mainly found in air conditioners and refrigerants. These compounds are now regulated because of the adverse effect they have on the Ozone layer.

Other factors that have an effect on the Earth's climate are:

Aerosols

Atmospheric Aerosols

• These alter the climate in two ways - Infrared and solar radiation is absorbed and scattered, and the chemical and microphysical properties of clouds are changed,including their extent and lifetime.

The scattering of solar radiation acts to cool the planet, while absorption of solar radiation by aerosols warms the air directly instead of allowing sunlight to be absorbed by the surface of the Earth. This leads to negative effects on the Earth's climate.

Human Aerosols

Activity by humans contributes to the atmosphere's increase in aerosols in various ways, accelerating the negative effects the aerosols have on the climate.

• Dust - The agricultural processes produce this as a bi-product.
• Biomass Burning - This is a combination of soot particles and organic droplets.
• Exhaust Emissions - These are produced by vehicles which generate a cocktail that is rich in pollutants and are either aerosols from the very beginning or have been converted by a chemical reaction to form aerosols in the atmosphere.
• Industrial Processes - Aerosols are produced in a wide variety of industrial processes because of what is being burned or what the manufacturing process is producing at that time.

Land Use

Cutting down forests in order to create farmland has caused changes to how much sunlight is now being reflected back into space (the albedo surface) from the ground. Greenhouse gases and their emissions have caused changes that have been estimated at about 1/5th which are being forced on climate change globally, and roughly half of land use changes have occurred throughout the industrial era.

The replacement of forests due to grazing lands and agricultural cropping over North America and Eurasia has contributed to climate change, just as deforestation at high latitudes has along with previously forested areas where solar energy reflects off of snow that covers the land. The snow which is found on trees reflects around half of the sunlight that falls on them; however, open ground that is covered in snow will reflect around two-thirds.

The increased solar energy over North America and Eurasian regions of agriculture has had a cooling effect.

Other changes created on the surface of the land from human activities include:

• Tropical deforestation, which changes evapotranspiration rates (this is water vapour and the amount which is put into the atmosphere from trees through evaporation and transpiration). This why we need to buy FSC products including FSC wooden blinds to help with the efforts of planting new trees.
• Surface albedo is increased by desertification.
• Plus the effects that agriculture has on the characteristics of soil moisture.

Analyses indicate that the clearing of forests for irrigated farming and forest clearing in semi-arid and arid lands are two important sources of land cover changes that are climatically major.