Pollution is any undesirable change in physical, chemical or biological characteristics of air, land, water or soil. Agents that bring about such an undesirable change are called as pollutants.

Pollutants can be solid, liquid or gaseous substances present in greater concentration than in natural abundance and are produced due to human activities or due to natural happenings.

Causes of Pollution:

1. Commercial or Industrial waste
2. Forest fires
3. Hazardous waste

Types of pollution:

1. Air Pollution
2. Noise Pollution
3. Water Pollution
4. Soil Pollution
5. Radioactive Pollution
6. Light Pollution
7. Nitrogen pollution

Greenhouse gases and global warming:

Greenhouse gases are another source of air pollution. Greenhouse gases such as carbon dioxide and methane occur naturally in the atmosphere. In fact, they are necessary for life on Earth. They absorb sunlight reflected from Earth, preventing it from escaping into space. By trapping heat in the atmosphere, they keep Earth warm enough for people to live. This is called the greenhouse effect.

But human activities such as burning fossil fuels and destroying forests have increased the amount of greenhouse gases in the atmosphere. This has increased the greenhouse effect, and average temperatures across the globe are rising.

Controlling measures:

1. Improving public transport
2. Limiting the number of polluting vehicles on the road
3. Introducing less polluting fuel
4. Strict emission regulations
5. Improved efficiency for thermal power plants and industries
6. Moving from diesel generators to rooftop solar
7. Increased use of clean renewable energy
8. Electric vehicles
9. Removing dust from roads
10. Regulating construction activities
11. Stopping biomass burning, etc.

Climate Change:

The Earth’s climate has changed throughout History. In the last 650,000 years there have been Several cycles of glacial and warm periods each Lasting thousands or millions of years. Most Of these climate changes are attributed to very Small variations in earth’s orbit that changes the amount of solar energy our planet receives.

It is understood that at present the Earth’s Climate is getting warmer which is referred to as ’Global Warming’. Earth’s temperature has gone up about one degree Fahrenheit in the Last 100 years. This is a very small change but Small changes in earth’s temperature can have big effects. Some effects are already happening Such as melting of glaciers, rise in the level of Oceans, prolonged droughts, excessive rain and Floods, etc.

Reasons for Climate change:

Burning fossil fuels emits gases into the Atmosphere. Burning fossil fuel to provide Energy, coupled with the effects of major Transportation and deforestation causes a rapid Increase in global temperatures. This can change the climate of a place.

Effects of climate change – Scientists had Predicted in the past that the result from global Climate change are now occurring, loss of seaIce, accelerated sea level rise and longer, more Intense heat waves.

1. Temperatures will continue to rise – Experts agree that greenhouse gases which Trap heat and prevent it from leaving the Earth’s atmosphere are mostly responsible for the temperature spike.
2. Frost- free season (and growing season) will lengthen – it could actually have Detrimental effects on the crops we grow.
3. Warmer weather helps pests survive longer which can destroy crops. Rising Temperatures are also expected to contribute to a shift in areas which are agriculturally most productive and the crops that grow there.
4. Changes in precipitation patterns – The Contrast between wet and dry areas will Increase globally. In other words, the wet Areas will get wetter and the dry areas will get drier.
5. More droughts and heat waves – With rising Temperatures and shifting rainfall patterns, Heat waves and droughts are increasing in Frequency and intensity.
6. Sea level rise – Scientists have determined that global sea level has been steadily rising Since 1900 at a rate of at least 0.1 to 0.25 Centimeter per year. Sea level can rise by two different mechanisms with respect to Climate change.
7. Arctic likely to become ice-free – The Arctic Ocean is expected to become essentially ice Free in summer before mid-century.Response to Climate Change

There are two main responses to climate Change:

Mitigation – which addresses the root causes of climate change, by reducing greenhouse Gas emissions.

Adaptation – seeks to lower the risks posed by the consequences of climatic changes. Both approaches will be necessary to deal with the global changes that have already been set in motion.

Mitigation measures:

It is important that we learn how to reduce Climate change, and put them into practice now, before it is too late.

1. Cleaner alternative energy sources: One important way to fight climate change is to Reduce our reliance on and usage of fossil Fuels, and depend on alternative renewable And greener sources of energy such as wind Energy, solar energy, water or hydropower, Biomass, and geothermal energy.
2. Energy saving tips – we can adopt energy Saving tips by investing in more expensive Energy-saving appliances like the compact Fluorescent light (CFL) bulbs, Air-Conditioners, refrigerators etc. Switching off Our electrical appliances when not in use.
3. Green driving tips – The best strategy to Reduce toxic gas emissions is definitely to Reduce the use of automobiles. Use public Transport, carpooling, use of electricity Powered cars or two wheelers can be an Alternative.
4. Reduce – Reuse – Recycle practices – Reducing, reusing and recycling helps us Conserve resources and energy, and reduce Pollution and greenhouse gas emissions Produced thereby.
5. Re-forestation – The cleanest and most efficient remover of carbon dioxide from our atmosphere actually is nothing but Green plants and trees. The rate at which We are cutting down our trees and forests To make way for human developments has Greatly reduced the earth’s ability to remove Carbon dioxide from the atmosphereOrganic farming – Soils are an important Sink for atmospheric carbon dioxide.

Nevertheless, deforestation making way for conventional agriculture is increasingly Depleting this sink. Sustainable and organic Agriculture helps to counteract climate Change by restoring soil organic matter Content as well as reduce soil erosion and improve soil physical structure. Organic Farming uses natural fertilizers and helps aintain crop yields.

Environmental Impact Assessment:

Every country strives to progress ahead. One aspect of progress is economic development through manufacturing and trading. Every Country builds industries which provide Employment, serve the consumers needs and help to generate revenue. The dominant Pattern of development that humankind hasFollowed in recent decades has brought about large scale changes in the earth systems. We Are already feeling the impact of these changes Upon our health, livelihoods and safety. On the Other hand, the fruits of development are not Equally distributed. Some countries and some Communities have a high standard of living, while Others are not able to meet their basic needs development projects in the past were Undertaken without any consideration about Their environmental consequences. As a result Rivers and lakes have been polluted, air pollution Has reached threatening levels and pilling of Domestic and industrial wastes has resulted in Land degradation. Industrialization and economic Growth provided material comforts but at the Same time deteriorated the quality of life.

The Objective of EIA:

• To identify, predict and evaluate the Economic, environmental and social impact of development activities.
• To provide information on the Environmental consequences for decision Making.
• To promote environmentally sound and Sustainable development through the Identification of appropriate alternatives and mitigation measures.

Steps in the EIA Process:

The eight steps of the EIA process:

1. Screening: First Stage of EIA, which determines whether the proposed project, equires an EIA and if it does, then the level Of assessment required.
2. Scoping: This stage identifies the key Impacts that should be investigated. This Stage also defines the time limit of the study.

• Impact analysis: This stage of EIA identifies and predicts the likely environmental andSocial impact of the proposed project and Evaluates the significance.

1. Mitigation: This step in EIA recommends the actions to reduce and avoid the potential adverse environmental consequences of Development activities.
2. Reporting: This stage presents the result of EIA in a form of a report to the decision-Making body and other interested parties.
3. Review of EIA: It examines the adequacy And effectiveness of the EIA report and Provides the information necessary for Decision –making.

• Decision-making: It decides whether the project is rejected, approved or needs Further change.
• Post monitoring: This stage comes into Play once the project is commissioned. It Checks to ensure that the impacts of the Project do not exceed the legal standards and implementation of the mitigation Measures are in the manner as described in The EIA report.

Environmental Impact Assessment in India:

EIA was introduced in India in 1978, with Respect to river valley projects. On 27 January 1994, the Union Ministry of Environment and Forests (MEF), Government of India, under the Environmental (Protection) Act 1986, made Environmental Clearance (EC) mandatory for expansion or modernisation or for setting up new projects listed in Schedule 1 of the Notification. Since then there have been 12 Amendments made in the EIA notification of 1994. Both central and state authorities share the responsibility of EIA’s development and Management. EIA is now mandatory for 30 Categories of projects, and these projects get Environmental Clearance (EC) only after the EIA requirements are fulfilled.

The MoEF recently notified new EIA Legislation in September 2006. The notification makes it mandatory for all projects to get Environment clearance from the central Government under the following categories:

1. Industries
2. Mining
3. Thermal power plants
4. River valley projects
5. Infrastructure and CRZ (Coastal Regulation Zone)
6. Nuclear power projects

However, the new legislation has entrusted the decision of clearing projects on the State government depending on the size/Capacity of the project. EIA appraises the Environmental health and social implications of planned developmental projects. It thus Links environment with development. The goal Of EIA is to ensure environmentally safe and Sustainable development.