Atmospheric Overview

– Biplob Deb, Faculty, Dept. of Chemistry, Notre Dame College & Director, Notre Dame Nature Study Club.

The atmosphere surrounding our planet is composed of a number of gases, mostly nitrogen and oxygen, with much smaller concentration of others like Carbon dioxide and Ozone. These gases play an important role in supporting life on earth, for example: Oxygen is breathed in to fuel chemical reactions in the organisms; a layer of Ozone, 15 to 30 km. above us in the Stratosphere, shields us from harmful Ultraviolet-B (UV-B) rays from the Sun; and Greenhouse gases, like Carbon dioxide, maintain the surface temperature of the earth at an average of 15°C.

Some of the things that we do changes the nature of the atmosphere – impacting on air quality, the levels of UV radiation reaching the earth and the climate that all plants and animals depend upon. The main sources of pollution affecting air quality in the metropolitan area are motor vehicles, while in regional centres industry has the largest impact. The Environment Protection Authority monitors pollutants in a number of metropolitan and regional locations to determine the air quality that is enough to maintain human health. Air quality in most areas of the world is not so good, although there are occasions when levels of pollutants fail to meet national guidelines.

Unlike air quality issues, which are generally localised, Ozone depletion and climate change are global problems that the whole world contributes to, and feels the effect of. Worldwide problems require solutions that involve every country. Ozone depletion damages plants, including agricultural crops and creates health problems for humans, including eye damage and skin cancer. Following the implementation of international controls, the world’s emissions of Ozone Depleting Substances have reduced dramatically and it is expected that the first signs of Ozone layer recovery will be noticed in the next 10 to 15 years. Full recovery of the Ozone layer is expected by 2050, but may be delayed by as much as 50 years, due to climate change and the use of ozone depleting substances in developing countries.

Emissions of greenhouse gases from around the world continue to increase. The use of fossil fuels in transport as well as in domestic and industrial energy consumption (such as electricity from fossil fuel power stations and the use of natural gas), are the biggest contributors to greenhouse gas emissions.

What Impact Does Poor Air Quality Have?

Some of the environmental, social, public health and economic effects of poor air quality are listed below to illustrate the issue’s broader significance for sustainability.

  • Excessive Carbon Monoxide inhibits the uptake of Oxygen through the bloodstream and can affect visual perception, mental concentration and heart function.
  • Nitrogen dioxide, Sulphur dioxide, Ozone and fine particulate matter have been associated with respiratory problems and increased mortality rates.
  • Lead can result in reduced mental capability, particularly in children, and reduced fertility in grown up people.
  • Volatile organic compounds (i.e. air toxics) have been associated with a wide variety of health effects, including respiratory irritation, Cancer and damage to the internal organs.
  • Just as it affects humans, poor air quality adversely affects the health of vegetation and animals and even the health of the marine environment.
  • Some air pollutants can also be deposited in soil or water, becoming part of terrestrial, marine and aquatic environmental systems where they can affect living organisms. Not all effects may be visible, but can still result in damage such as growth inhibition, which in crops and animals grown for commercial purposes has a directly measurable impact on the economy and society.
  • Poor air quality has also an economic impact through increased medical costs, reduced workforce productivity, and damaged buildings, cars and monuments.

What Can You Do to Help?

Here are some actions we can take to help reduce our impact on our environment and save money. Each action is a step in the right direction in our journey towards ecologically sustainable development. Recommendations include the following:-

  • Keep your car regularly serviced and your tyres inflated to the manufacturer’s specifications, to ensure that your car is running efficiently not producing excessive pollutants.
  • When you trade in your old car, replace it with a fuel-efficient, low emission car. Also, check out the fuel consumption label, which is now displayed on new cars. For commercial vehicles 3.5 tonnes gross vehicle mass and over, the Alternative Fuel Conversion Program is available.
  • Try riding a bike or walking instead of a car – save money, help the environment and at the same time reap the fitness benefits! If walking or riding isn’t possible, then use buses, trams or trains whenever you can, to reduce greenhouse gas emissions.
  • Use energy efficient appliances. Look for the ENERGY STAR logo next time you’re buying a computer, printer or scanner, TV, VCR, audio or DVD product; or the ENERGY RATING on the next air conditioner, clothes dryer, clothes washer, dishwasher, fridge or freezer you purchase.
  • If renovating or building, do so using energy efficient designs and materials.
  • Turn off unnecessary electrical appliances at the power point wherever possible.
  • Make it your goal to purchase ‘Green Power’ – power generated from clean, renewable energy sources. Businesses, councils and government agencies can use Green Power to easily reduce their contribution to the greenhouse effect, and to position themselves as clean green organizations. Alternatively, we can generate our own green power. Investigate the Solar Hot Water Rebate, Photo-voltaic Rebate and the Remote Renewable Power Generation grants.
  • Limit wood fires at home and outside like campfire and cooking. Wear warmer clothes as your first action to keep warm.
  • Schools can get involved with Airwatch, a program for primary and secondary schools where students can become pollution watch-dogs in their local area.


  1. Calder, I.C., Maynard, E.J. and Heyworth, J.S. (1994). Port Pirie Lead Abatement Program, 1992. Environmental Geochemistry and Health, 16, 137-145.
  2. Environment Protection Authority (EPA) (2002). Air Quality Monitoring Report: Annual Report No 4 – Ambient Air Quality in South Australia (draft). Air Quality Section (AQS), Monitoring and Evaluation Branch Environment Protection Authority, Adelaide.
  3. Nature Study – the quartarly magazine of NSSB; July-Sept.2006; Nature Study Society of BD., Motijheel, Dhaka.