Today, more and more harmful human activities around the globe have become a threat to the natural environment, its biodiversity and the longevity of human generation. Therefore, as humans, we have to find global solutions to overcome these environmental problems. Hence, in my first post, I would like to bring you through hot topics on global environmental problems. They are Global warming, depletion of the ozone layer, Acid rains and Desertification.

Global warming

This is due to the rising temperature of the surface of the earth and is a result of the accumulation of greenhouse gases. Hence, this is the Greenhouse effect.

Greenhouse effect

The earth normally receives sun rays of 0.2-4 micrometer wavelength. However, only 50% of them reach the earth. The earth absorbs these rays to generate heat. After that, these heat rays are emitted to the atmosphere as infrared radiation of 4-100 micrometer wavelength. Because of that, it helps to cool the surface of the earth.

What are the causes?

However, an excessive amount of carbon dioxide (CO2), water vapors (H2O(g)), methane(CH4) and ozone(O3) in the atmosphere interfere emitting infrared radiation from the earth. As a result, this increases the normal temperature of the surface of the earth. Not only that, nitrous oxide and chlorofluorocarbons (CFC) also cause this Greenhouse effect. Likewise, vehicles, factories, refrigerators and air condition machines are the main sources that add these gases to the atmosphere.

There are several harmful effects of global warming. They are rising sea level, risk of extinction of species, climate changes around the globe, desertification and emerging and re-emerging of diseases among the human population.

What we can do is;

• Reduce energy use for day-to-day activities like using LED bulbs for lighting

purposes, establishing housing solar power systems and using alternative

energy sources like wind power.

• Changing transportation from private transport to public transport to reduce

burning fossil fuel.

• Plant a tree and stop deforestation.

Depletion of the Ozone layer

The ozone layer acts as a protective barrier of the earth by absorbing 97%-99% of infrared radiations(UV-B) of the sun. Since 1975, this layer has gradually been depleted due to air pollution. As a result, an ozone hole was first discovered in 1982 above the Antarctic continent. Similarly, it has been discovered the same size of the ozone hole above the Arctic ocean. Also, it has been identified that CFC is the most harmful gas for the Ozone layer.

There are several harmful effects of depletion of the Ozone layer. They are higher risk of skin cancers, immunodeficiency state, cataracts and climate changes around the globe.

What we can do is;

• Proper maintaining of air conditioners.

• Encourage to use public transport to minimize air pollution.

• Avoid using products that contain harmful gases to ozone layers.

Acid rains

Developed countries burn coal and petroleum products to generate their energy needs. During this process, they emit chemical oxides of nitrogen and surfer as by-products to higher layers of the atmosphere. Further, these oxides become nitric acid(HNO3) and sulphuric acid(H2SO4) after reacting with water vapors. As a result, these acids come to the earth as rain or ice or mist or fog calling itself as Acid rain (pH is less than 5.2).

There are several harmful effects of acid rain. They are damages to trees, vegetation and aquatic animals, changes in soil biology and chemistry by robbing essential nutrients, damages to buildings, historic monuments and statues, acidification of the ocean and a higher risk of respiratory illness among the human population.

What we can do is;

• Save energy and minimize the production of electricity/energy.

• Use cleaner fuel for everyday consumption.

• Use alternate energy supplies.

Desertification

This is the degradation of biologically productive and fertile land into dry land due to man's activity. So that, over 200,000-square miles around the world have been becoming desert each year. Therefore, you can see mass desertification in countries like Africa, South America and China Hence, scientists have shown the inappropriate agricultural, irrigating and farming protocols, and over-grazing as the main causes of

Desertification.

There are several harmful effects of desertification. They are the changes in natural vegetation, dust and sand storms, threats to global food security and higher frequency of drought and flooding.

What we can do is;

• Proper management of agriculture, farming and irrigation.

• Educating the public.

• Re-plant trees as "Great green wall initiative".

What have we done so far?

Most of the countries around the world have signed different conventions and protocols to overcome/minimize these global environmental problems. The basal convention, Marpol convention, Montreal protocol and Kyoto protocol are some of the most important historical milestones for this effort.

• Basal Convention

This is the convention on the control of the trans-boundary movement of hazardous waste and their disposal. In the Basal city of Switzerland, 173 countries signed this agreement in 1989.

• Marpol Convention

This is the convention for the prevention of marine pollution by petroleum products. It was initially signed in 1973. However, it was revised several times by adding different regulations. They are regulations on prevention of pollution by oil (1983), noxious liquid substances (1983), garbage from ships (1988), harmful substances carried by sea in packaged form (1992), sewage from ships (2003), and prevention of air

pollution from ships(2005).

• Montreal Protocol

This is the protocol on substances that deplete the ozone layer. It was signed in 1987 in Canada. It is effective since 1989. According to this protocol, the aim was to stop/minimize emitting CFC and other harmful noxious gases that deplete the ozone layer by the year 2000. However, the aim was achieved by 1996.

• Kyoto Protocol

This was the protocol for the reduction of greenhouse gases in the atmosphere. In 1997, 37 countries signed this agreement in japan. Moreover, 187 countries have singed and agreed on this protocol by the end of 2009. Further, industrialized countries have reduced emitting greenhouse gases by 5%-8% in 2012.

Not only those efforts, but there are also the latest conventions, protocols, and agreements among nations to protect mother nature and mankind. Therefore, we have a duty for maintaining sustainable development towards environmental management.