The Earth is wrapped in a blanket of air called the 'atmosphere', which is made up of several layers of gases. The sun is much hotter than the Earth and it gives off rays of heat (radiation) that travel through the atmosphere and reach the Earth. The rays of the sun warm the Earth, and heat from the Earth then travels back into the atmosphere. The gases in the atmosphere stop some of the heat from escaping into space. These gases are called greenhouse gases and the natural process between the sun, the atmosphere and the Earth is called the 'Greenhouse Effect', because it works the same way as a greenhouse. The windows of a greenhouse play the same role as the gases in the atmosphere, keeping some of the heat inside the greenhouse.

THE NATURAL GREENHOUSE EFFECT

The atmosphere has a number of gases, often in tiny amounts, which trap the heat given out by the Earth.

To make sure that the Earth's temperature remains constant, the balance of these gases in the atmosphere must not be upset.

The GREENHOUSE GASES are very important and are mainly: water vapour occurs naturally in the atmosphere. carbon dioxide produced naturally when people and animals breathe. Plants and trees absorb carbon dioxide to live. Volcanoes also produce this gas. Carbon dioxide is not the same as carbon monoxide (See Air Quality) methane comes from cattle as they digest their food. The gas also comes from fields where rice is grown in paddy fields. nitrous oxide when plants die and rot, nitrous oxide is produced. ozone occurs naturally in the atmosphere.

THE ENHANCED GREENHOUSE EFFECT

Some of the activities of man also produce greenhouse gases. These gases keep increasing in the atmosphere. The balance of the greenhouse gases changes and this has effects on the whole of the planet.

Burning fossil fuels - coal, oil and natural gas - releases carbon dioxide into the atmosphere. Cutting down and burning trees also produces a lot of carbon dioxide.

A group of greenhouse gases called the chlorofluorocarbons, - which are usually called CFCs, because the other word is much too long! - have been used in aerosols, such as hairspray cans, fridges and in making foam plastics. They are found in small amounts in the atmosphere. They are dangerous greenhouse gases because small amounts can trap large amounts of heat.

Because there are more and more greenhouse gases in the atmosphere, more heat is trapped which makes the Earth warmer. This is known as GLOBAL WARMING.

A lot of scientists agree that man's activities are making the natural greenhouse effect stronger. If we carry on polluting the atmosphere with greenhouse gases, it will have very dangerous effects on the Earth.

THE EFFECTS

With more heat trapped on Earth, the planet will become warmer, which means the weather all over Earth will change. For example, summers will get hotter, and winters too. This may seem a good idea, but the conditions we are living in are perfect for life, and a large rise in temperature could be terrible for us and for any other living thing on Earth.

At the moment, it is difficult for scientists to say how big the changes will be and where the worse effects will occur.

The Weather

In Britain, winter and summer temperatures will increase and the weather will be warmer. In winter it may also rain more but in summer it may become drier.

In other parts of the world, the effects will be different, some places will become drier and others will be wetter. Although most areas will be warmer, some areas will become cooler. There may be many storms, floods and drought, but we do not know which areas of the world will be affected.

All over the world, these weather changes will affect the kind of crop that can be grown. Plants, animals and even people may find it difficult to survive in different conditions.

Sea Levels

Higher temperatures will make the water of the seas and oceans expand. Ice melting in the Antarctic and Greenland will flow into the sea.

All over the world, sea levels may rise, perhaps by as much as 20 to 40 cm, by the beginning of the next century.

Higher sea levels will threaten the low-lying coastal areas of the world, such as the Netherlands and Bangladesh. Throughout the world, millions of people and areas of land will be at danger from flooding. Many people will have to leave their homes and large areas of farmland will be ruined because of floods. In Britain, East Anglia and the Thames estuary will be at risk from the rising sea.

Farming

The changes in the weather will affect the types of crops grown in different parts of the world. Some crops, such as wheat and rice grow better in higher temperatures, but other plants, such as maize and sugarcane do not. Changes in the amount of rainfall will also affect how many plants grow.

The effect of a change in the weather on plant growth may lead to some countries not having enough food. Brazil, parts of Africa, south-east Asia and China will be affected the most and many people could suffer from hunger.

Water

Everywhere in the world, there is a big demand for water and in many regions, such as the Sahara in Africa, there is not enough water for the people. Changes in the weather will bring more rain in some countries, but others will have less rain.

In Britain, the Southeast will be at risk from drought.

IN DANGER!

Plants & Animals

It has taken million of years for life to become used to the conditions on Earth. As weather and temperature changes, the homes of plants and animals will be affected all over the world.

For example, polar bears and seals, will have to find new land for hunting and living, if the ice in the Arctic melts.

Many animals and plants may not be able to cope with these changes and could die. This could cause the loss of some animal and plant species in certain areas of the world or everywhere on Earth.

People

The changes in climate will affect everyone, but some populations will be at greater risk. For example, countries whose coastal regions have a large population, such as Egypt and China, may see whole populations move inland to avoid flood risk areas. The effect on people will depend on how well we can adapt to the changes and how much we can do to reduce climate change in the world.

Go to the next sheet on the Ozone Hole.......

Source : http://www.clean-air-kids.org.uk/globalwarming.html

Agenda 21

Agenda 21, established at the 1992 United Nations Conference on Environment and Development, or "Earth Summit", in Rio de Janeiro, Brazil, is the blueprint for sustainability in the 21^st century. Agenda 21 is a commitment to sustainable development, which was agreed by many of the world's governments. Nations that have pledged to take part in Agenda 21 are monitored by the International Commission on Sustainable Development, and are encouraged to promote Agenda 21 at the local and regional levels within their own countries. Agenda 21 addresses the development of societies and economies by focusing on the conservation and preservation of our environments and natural resources.

The Conventions, Principles and Declarations of the Earth Summit, provide guidelines to deal with the problems of poverty, hunger, resource consumption and the deterioration of ecosystems. Agenda 21 provides a format for this to happen, detailing an action plan for sustainable development and establishing targets for actions that combine economic development and environmental protection. Agenda 21:

• Is the blueprint for sustainability in the 21^st century.
• Provides options for combating the deterioration of land, air and water, whilst conserving habitats and their diversity.
• Deals with poverty, over consumption, health and education.
• Promotes roles for all. Everyone – governments, business, trade unions, scientists, teachers, indigenous people and youth – have roles to play in achieving sustainable development and should be involved in the decision making processes.
• Encourages the reduction of environmentally and socially detrimental processes, but within a framework which allows economic success.

Presently a nation’s wealth is gauged by its financial standing, and the more money the better. Agenda 21 promotes the attitude that a nation’s wealth should also account for the full value of its natural resources. Agenda 21 also encourages nations to consider the costs of environmental degradation. In addition, to reduce the risk of damage, environmental assessments should be carried out and where degradation does occur, those responsible should bear the costs.

Agenda 21 highlights the need to eradicate poverty. One of the major problems facing poorer nations is their lack of resources and ability to live sustainably. Developed nations have taken on the responsibilities of assisting poorer nations to reduce their environmental impacts and achieve sustainable development.

Agenda 21 asks governments to integrate sustainable development into their national strategies and highlights the importance of involving non-governmental organisations (NGOs) and the public in the process. For sustainable development to work, issues must be tackled on a local, national and international level and nations must work ‘towards international agreements which respect the interests of all and protect the integrity of the global environmental and developmental system.’

Source : http://www.sustainable-environment.org.uk/Action/Agenda_21.php

Environment > Air Pollution

One of Earth's most important natural resources is its atmosphere. The atmosphere contains air without which plants and animals could not survive. It contains greenhouse gases which keep the planet naturally warmer than it would be otherwise, maintaining an average global temperature above freezing that allows water to exist in its liquid state, a necessary condition for most life. If mankind is to protect and preserve this unique natural resource for future generations as well as other ecosystems, it must continue to address the problem of air pollution which affects the atmosphere from the local to the global scale.


Air Pollution and concern about air quality are not new. Complaints were recorded in the 13^th century when coal was first used in London. Since the middle of the 19^th century, the atmosphere of the major British cities was regularly polluted by coal smoke in winter, giving rise to an infamous mixture of fog and smoke known as smog.

In the 1970s the transboundary effects of industrial air pollution become known as acid rain. Acid rain is a widespread term used to describe all forms of acid precipitation such as rain and snow. Atmospheric pollutants, particularly oxides of sulphur and nitrogen react with water in the atmosphere to form sulphuric and nitric acid, causing precipitation to become more acidic when converted to sulphuric and nitric acids, hence the term acid rain. Acid deposition, acid rain and acid precipitation all relate to the chemistry of air pollution and moisture in the atmosphere. Scientists generally use the term acid deposition but all three terms relate to the same issue.

Acid rain is particularly harmful to vegetation as the acid in the rain changes the pH of the soil and leeches away important minerals. The amount of acid rain that an ecosystem can tolerate is known as its critical load. After the sulphuric and nitric acids have formed in the atmosphere, they can travel long distances with the wind before being deposited. In fact, much of the acid rain found in Scandinavia originated from the UK. In response to these problems, a number of agreements, including the Convention on Long-Range Transboundary Air Pollution (Geneva, 1979), have set out to reduce acid rain.

Although acid rain remains an international concern, poor air quality in cities is now considered to be a more pressing environmental problem. Today poor air quality can be mainly attributed to the production and consumption of energy, industrial processes and road transport. The main pollutants associated with poor air quality are sulphur dioxide (SO₂), nitrogen oxides (NOx), particulates (PM₁₀), and volatile organic compound (VOCs). These pollutants can lead to respiratory problems, particularly amongst the young and elderly.

Transport in particular is becoming an increasing source of air pollution. The transport related problems experienced now are likely to worsen according to the projected increase in traffic. Individually, a vehicle engine is not a particularly important source of pollution. Collectively however, vehicles represent a major source of air pollution in the UK and throughout the world. The best way to reduce the threat of air pollution is to use cleaner fuel and less of it, and to adopt more sustainable modes of transport like public transport, walking and cycling.

The UK Government has recognised the problems that air pollution causes for the environment and for society and in 1997 published the first National Air Quality Strategy, setting air quality standards for today and making commitments to achieve new air quality objectives by 2005.

Source : http://www.sustainable-environment.org.uk/Environment/Air_Pollution.php

Berita Hari Ini

Environmental and Sanitation

Visit the Widget Gallery

100 Topic Sustainable Environmental

In Your Home – Conserve Energy Clean or replace air filters on your air conditioning unit at least once a month. If you have central air conditioning, do not close vents in unused rooms. Lower the thermostat on your water heater to 120. Wrap your water heater in an insulated blanket. Turn down or shut off your water heater when you will be away for extended periods. Turn off unneeded lights even when leaving a room for a short time. Set your refrigerator temperature at 36 to 38 and your freezer at 0 to 5 . When using an oven, minimize door opening while it is in use; it reduces oven temperature by 25 to 30 every time you open the door. Clean the lint filter in your dryer after every load so that it uses less energy. Unplug seldom used appliances. Use a microwave when- ever you can instead of a conventional oven or stove. Wash clothes with warm or cold water instead of hot. Reverse your indoor ceiling fans for summer and winter operations as recommended. Turn off lights, computers and other appliances when not in use. Purchase appliances and office equipment with the Energy Star Label; old refridgerators, for example, use up to 50 more electricity than newer models. Only use electric appliances when you need them. Use compact fluorescent light bulbs to save money and energy. Keep your thermostat at 68 in winter and 78 in summer. Keep your thermostat higher in summer and lower in winter when you are away Insulate your home as best as you can. Install weather stripping around all doors and windows. Shut off electrical equipment in the evening when you leave work. Plant trees to shade your home. Shade outside air conditioning units by trees or other means. Replace old windows with energy efficient ones. Use cold water instead of warm or hot water when possible. Connect your outdoor lights to a timer. Buy green electricity - electricity produced by low - or even zero-pollution facilities (NC Greenpower for North Carolina - www.ncgreenpower.org). In your home-reduce toxicity.

In Your Home – Reduce Toxicity Eliminate mercury from your home by purchasing items without mercury, and dispose of items containing mercury at an appropriate drop-off facility when necessary (e.g. old thermometers). Learn about alternatives to household cleaning items that do not use hazardous chemicals. Buy the right amount of paint for the job. Review labels of household cleaners you use. Consider alternatives like baking soda, scouring pads, water or a little more elbow grease. When no good alternatives exist to a toxic item, find the least amount required for an effective, sanitary result. If you have an older home, have paint in your home tested for lead. If you have lead-based paint, cover it with wall paper or other material instead of sanding it or burning it off. Use traps instead of rat and mouse poisons and insect killers. Have your home tested for radon. Use cedar chips or aromatic herbs instead of mothballs. In Your Yard Avoid using leaf blowers and other dust-producing equipment. Use an electric lawn- mower instead of a gas-powered one. Leave grass clippings on the yard-they decompose and return nutrients to the soil. Use recycled wood chips as mulch to keep weeds down, retain moisture and prevent erosion. Use only the required amount of fertilizer. Minimize pesticide use. Create a wildlife habitat in your yard. Water grass early in the morning. Rent or borrow items like ladders, chain saws, party decorations and others that are seldom used. Take actions that use non hazardous components (e.g., to ward off pests, plant marigolds in a garden instead of using pesticide). Put leaves in a compost heap instead of burning them or throwing them away. Yard debris too large for your compost bin should be taken to a yard-debris recycler.

In Your Office Copy and print on both sides of paper. Reuse items like envelopes, folders and paper clips. Use mailer sheets for interoffice mail instead of an envelope.Use mailer sheets for interoffice mail instead of an envelope. Set up a bulletin board for memos instead of sending a copy to each employee. Use e-mail instead of paper correspondence. Use recycled paper. Use discarded paper for scrap paper. Encourage your school and/or company to print documents with soy-based inks, which are less toxic. Use a ceramic coffee mug instead of a disposable cup. Ways To Protect Our Air Ask your employer to consider flexible work schedules or telecommuting. Recycle printer cartridges. Shut off electrical equipment in the evening when you leave work. Report smoking vehicles to your local air agency. Don't use your wood stove or fireplace when air quality is poor. Avoid slow-burning, smoldering fires. They produce the largest amount of pollution. Burn seasoned wood - it burns cleaner than green wood. Use solar power for home and water heating. Use low-VOC or water-based paints, stains, finishes and paint strippers. Purchase radial tires and keep them properly inflated for your vehicle. Paint with brushes or rollers instead of using spray paints to minimize harmful emissions. Ignite charcoal barbecues with an electric probe or other alternative to lighter fluid. If you use a wood stove, use one sold after 1990. They are required to meet federal emissions standards and are more efficient and cleaner burning. Walk or ride your bike instead of driving, whenever possible. Join a carpool or vanpool to get to work.

Ways to Use Less Water Check and fix any water leaks. Install water-saving devices on your faucets and toilets. Don't wash dishes with the water running continuously. Wash and dry only full loads of laundry and dishes. Follow your community's water use restrictions or guidelines. Install a low-flow shower head. Replace old toilets with new ones that use a lot less water. Turn off washing machine's water supply to prevent leaks. Ways to Protect Our Water Revegetate or mulch disturbed soil as soon as possible. Never dump anything down a storm drain. Have your septic tank pumped and system inspected regularly. Check your car for oil or other leaks, and recycle motor oil. Take your car to a car wash instead of washing it in the driveway. Learn about your watershed. Create Less Trash Buy items in bulk from loose bins when possible to reduce the packaging wasted. Avoid products with several layers of packaging when only one is sufficient. About 33 of what we throw away is packaging. Buy products that you can reuse. Maintain and repair durable products instead of buying new ones. Check reports for products that are easily repaired and have low breakdown rates. Reuse items like bags and containers when possible. Use cloth napkins instead of paper ones. Use reusable plates and utensils instead of disposable ones. Use reusable containers to store food instead of aluminum foil and cling wrap. Shop with a canvas bag instead of using paper and plastic bags. Buy rechargeable batteries for devices used frequently. Reuse packaging cartons and shipping materials. Old newspapers make great packaging material. Compost your vegetable scraps. Buy used furniture - there is a surplus of it, and it is much cheaper than new furniture.

Sanitation is vital for health

Readers of a prestigious medical journal were recently asked to name the greatest medical advance in the last century and a half. The result: better sanitation. In nineteenth-century Europe and North America, diarrhoea, cholera, and typhoid spread through poor sanitation was the leading cause of childhood illness and death; today, such deaths are rare in these regions. In developing countries, however, they are all too common, and recent research suggests that poor sanitation and hygiene are either the chief or the underlying cause in over half of the annual 10 million child deaths. Compelling, evidence-based analysis shows that hygiene and sanitation are among the most cost-effective public health interventions to reduce childhood mortality. Access to a toilet alone can reduce child diarrhoeal deaths by over 30 percent, and hand-washing by more than 40 percent.

Diarrhoeal diseases

Five thousand children die every day due to infectious diarrhoea, which is caused primarily by inadequate sanitation. Seventeen percent of under-five deaths are attributable to diarrhoeal diseases, making it the second largest killer of children, after pneumonia. Diarrhoea is also a major contributor to malnutrition and stunting.

Diarrhoeal diseases are often described as water-related, but more accurately should be known as excreta-related since the pathogens derive from faecal matter. The faecal-oral cycle« describes the principal routes of transmission of infectious diarrhoeal disease. This cycle is fuelled by the ive f’s fluid (drinking contaminated water); fields (the contamination of soil and crops with human faecal matter); fingers (unwashed hands preparing food or going into the mouth); food (eating contaminated food); and flies (spreading disease from faeces to food and water or directly to people – particularly problematic where open-air defecation is the norm).

Breaking the faecal-oral cycle, which depends primarily upon hand-washing and use of toilets or latrines that contain and sanitise faecal matter, saves children’s lives. In Salvador, Brazil, a recent city-wide sanitation drive has raised sanitation coverage rates from 26 percent to 80 percent.

A study on diarrhoeal morbidity in children under three was conducted in high and low-risk areas of the city. The overall prevalence of diarrhoea fell by 22 percent, but in the poorer areas where sanitation coverage was lowest to start with, prevalence fell by 43 percent.

source : http://esa.un.org