The world we live in has numerous characteristics, among which its environment is the most important one. It is really miraculous that in the infinite universe where thousands of galaxies exist that have thousands of stars in them, the life may exist only on the planet earth and it is only because of its environment. 

The distance of the earth from the sun, its temperature and other physical features exist in such a proportional way that life has become possible here. In addition, the interdependence of living beings on one another, their interactions and their impacts over the environment have certain proportional order, which is called eco-system by the scientists. If eco-system is disturbed in some way or the other, the life is disturbed and the contaminants that are released by human beings in the environment have the potential to disrupt it greatly and the capacity to endanger existence on earth. 

Though the earth’s environment has blessed humanity much by making the life possible for them, human beings, on the other hand, have not been able to repay it in a proper manner and have showed a certain degree of carelessness in this regard. Their advancement in science and technology and their construction of numerous industries have benefitted them much in certain ways but in certain other ways they have started disturbing their environment and may keep on doing so unless the people become vigilant and take measures to curb the situation. Unfortunately, these disturbances may harm the existence of human being themselves as the same environment is protecting them in certain ways.

The earth’s environment, as mentioned above, has the type of temperature which is suitable for life to exist; however, if we go deeper in its study there are certain revelations that may show how compassionate the environment is towards human. Among them, the presence of Ozone (O3) Layer is most crucial one. Ozone Layer, which was discovered by French physicists Henri Buisson and Charles Fabry, is basically high concentration of O3 present in the stratosphere (lower layer of atmosphere), about 20 – 30 km above earth surface. It is a layer that has the potential to protect the earth from the ultraviolet rays of the sun and thus keep the earth temperature normal. It is also claimed by scientists that in absence of Ozone Layer the plants’ tissues and humans’ skins may be burnt.

However, there are reports and studies that some sort of depletion in Ozone Layer has been observed. The depletion in ozone layer means that there has been decrease in the concentration of Ozone in the atmosphere. Certain theories suggest that the decrease in the layer has been around 4% per decade, while some others even claim that there has been larger decrease over earth poles in springtime, which is termed as Ozone Hole by the scientists.

The phenomenon of depletion in Ozone is basically related to the Atomic Halogens. Scientists have observed that these Halogens react with O3 and the reaction results in the destruction of O3. The important question, however, is from where these Halogens come in the atmosphere. Unfortunately, the main source of these Halogens is man-made Halocarbon refrigerants, which scatter in the atmosphere after photo-dissociation. The most familiar Halocarbons are Chlorofluorocarbon (CFC), Freons and Halons and are released by refrigerators and air-conditioners.

On the other hand there is a concept of Global Warming. According to the observations and studies of the scientists this phenomenon will increase the average temperature of the world that may result in the liquefying of the glaciers on the poles and may drown the whole world. Furthermore, substantial rise in temperature may upset the conditions of living on earth and may disrupt the eco-system and endanger the living conditions. Global Warming is intensified by Green House Gases, which basically include water vapors, Carbon dioxide, Methane, Nitrous oxide and Ozone.  However, nowadays, Hydro Flouro Carbons (HFCs), which are emitted by industries, are considered as Super Green House Gases and they have the potential to warm up the atmosphere of the earth to an alarming level.

It is important to note that with the rise of technology and industrialization there has been considerable rise in the release of CFCs and HFCs in atmosphere; therefore, it can also be observed that the developed countries of the world are the number one emitters of these gases (China and USA are among the top emitters). Some of the scientists believe that there should be urgent steps taken to reduce the emission of these gases in the atmosphere as Global Warming may bring doom to the world and human beings. However, the political decision makers are yet to play their part in this regard.

On political level there have been commitments to control the emission of Green House and Ozone depleting gases; among them the Montreal Protocol is the most important one. It was an international treaty that was ready for signature on September 16, 1987 and was enforced from January 1, 1989 and afterwards there have been many developments as well in the Protocol. However, it is yet to convince all the countries to act as per its demands, as countries have controversies regarding the Protocol.

China and USA have very recently pledged that they would exert efforts to decrease the emission of Green House gases. In a statement on June 9, 2013, both the countries agreed to work together and phase down the production of consumption of HFCs.
According to news sources the White House has said that a global phase down of HFCs could reduce carbon emissions by 90 Giga-tons by 2050 -- equivalent to around two full years’ worth of the world's greenhouse gas emissions.

The US-China statement also clarified that HFCs would remain within the scope of the Kyoto Protocol and the related UN Framework Convention on Climate Change "for accounting and reporting of emissions." The statement said that China and the United States would work together at the Montreal Protocol.

It is really important that the developed and leading nations of the world must feel their responsibilities the most. They must lead as an example and must also keep in consideration that they are damaging the atmosphere which is common for all the human beings belonging to different nations in the world. Therefore, they have the responsibility not to let the atmosphere deteriorate and human beings suffer.