The main reasons for the climate change are;

                                i.            Greenhouse gases

                               ii.            Changes in the solar activity

                              iii.            Movement of tectonic plates

                              iv.            Change in the earth’s orbit

                               v.            Volcanism

                              vi.            Meteor Strikes

 

There is a high correlation between temperature changes and solar activities but in the recent years greenhouse gases have become dominant in global heating. Tectonic movements and change in the earth’s orbit are effective, but  in the very long term. On the other hand particles that emerge from volcanic explosions or from a meteor strike (for example like in the prehistoric period) prevent sunlight to reach to the earth. As humans, among these we can only control greenhouse gas emissions; the most effective one.

 

Human made factors like urbanization, aerosols, CFC (Chlorofluorocarbons), fossil fuels, agricultural activities, deforestation and transportation can be stated as the factors, which are effective on climate change.

 

With the “industrial revolution” human activities have increased and accordingly the greenhouse emissions in the atmosphere. The main greenhouse gases are Carbon Dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). In addition, according to scientific researches CH₄ is 21 times and N₂O is 310 times effective than CO₂. These are also called anthropogenic gases and since 1750 these have markedly increased as a result of human activities. In global scale increases in carbon dioxide concentration are due primarily to fossil fuel use and land-use change, while those of methane and nitrous oxide are primarily due to agricultural activities. (IPCC Report) These gases absorb sun lights and causes increase in the earth’s temperature. Moreover, CFCs deplete ozone (O₃) layer in the atmosphere. However, in 1990 it was agreed to stop CFC usage until the 2000 in London Protocol, so today the usage of these gases have been taken under control.

Today, one of the most serious threats is global heating and effects of this can already be observed easily. According to IPCC report “Eleven of the last twelve years (1995 -2006) rank among the 12 warmest years in the instrumental record of global surface temperature since 1850 … Observations since 1961 show that the average temperature of the global ocean has increased to depths of at least 3000 m and that the ocean has been absorbing more than 80% of the heat added to the climate system. Such warming causes seawater to expand, contributing to sea level rise… Mountain glaciers and snow cover have declined on average in both hemispheres. Widespread decreases in glaciers and ice caps have contributed to sea level rise” (pp. 5, 7) Moreover, another crucial impact of decreases in glaciers is that this causes the salt density in the oceans to change and it is afraid that this would negatively affect Gulf Stream and accordingly west coast of Europe. It is not necessary to mention about the changes in annual precipitation and catastrophes that have occurred frequently in the last decade; like Katrina, El Niño, and La Niña etc.

 

Kyoto Protocol is being implemented since 2005. However some countries like USA and Australia have hesitations to implement this. Since their industries mainly dependent to fossil fuels they claim that if they give promises to decrease their emissions and implement this protocol, it would negatively affect their industries and the welfare level of their people. On the other hand, in USA in the federal level some states allocate important amount of resources for efficiency in energy usage and research and development studies for the renewable energy technologies. 

 

 In addition, recycling policies, renewable energy technologies, waste to energy implementations and energy efficiency have begun to gain importance in most of the countries. For example; by 2010 the EU aims to produce 21% of its electricity from renewable resources and plan to substitute highway transportation with railways to decrease CO₂ and N₂O emissions.

To conclude, especially in the last decade effects of global heating have become more obvious; the frequency of catastrophes has increased, annual precipitation rates have changed, glaciers and snow cover have declined and sea level has increased. What we are pursuing is the road to hell. However, yet it is not too late. Being more sensitive and creating policies for solution of these problems can save the earth.

 

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