Q. What is the greenhouse effect?
The greenhouse effect is a naturally occurring process. Light and ultraviolet radiation (UV) from the sun passes through the atmosphere before reaching the Earth. About one third of this radiation is reflected back into space by the atmosphere and by the Earth. The rest of the radiation is absorbed by the atmosphere and the Earth and it turns into heat. Some of this heat goes into space in the form of infrared radiation, but most of it remains to warm up the lower atmosphere and the surface of the Earth – the land and the oceans. This is known as the natural greenhouse effect.
A ‘blanket’ of naturally occurring greenhouse gases such as water vapour, carbon dioxide, methane, and nitrous oxide help to trap heat and without this layer of gases in the atmosphere, the Earth’s average temperatures would be around 34°C colder. The greenhouse effect works to keep the balance right. The Earth is kept warm enough to sustain plants and animals and when enough infrared radiation goes back out into space, the Earth doesn’t heat up too much.
Since the Industrial Revolution, human activity has increased the concentration of greenhouse gases in the atmosphere. This includes both naturally occurring greenhouse gases such as carbon dioxide and methane, and a number of man-made greenhouse gases such as sulphur hexafluoride, hydrofluorocarbons and perfluorocarbons. A higher level of greenhouse gases in the atmosphere has resulted in more infrared radiation being trapped which heats up the lower atmosphere. This is known as the enhanced greenhouse effect.
Q. What are greenhouse gases?
Gases that trap heat in the atmosphere are commonly referred to as greenhouse gases. Some greenhouse gases occur naturally and are emitted into the atmosphere by natural processes and through human activities. Other greenhouse gases are created and emitted solely through human activities.
The primary greenhouse gases in the Earth's atmosphere are:
• Water vapour (H2O)
• Carbon dioxide (CO2)
• Nitrous oxide (N2O)
• Methane (CH4)
• Ozone (O3)
Activities that produce greenhouse gases include:
• Burning fossil fuels such as coal, oil and gas.
• Using electricity generated by burning fossil fuels.
• Land clearing (when plants and trees are chopped down and left to rot or are burnt, the carbon stored in the wood is released into the atmosphere. Land clearing also causes carbon stored in the soil to be released).
• Some aspects of farming i.e. raising cattle and sheep, fertiliser use, etc.
• The breakdown of food and plant waste and sewerage.
• Some industrial processes, e.g. making cement and aluminium.
(Source: Department of Environment, Water, Heritage and the Arts, Global Warming Cool it, http://www.environment.gov.au/settlements/gwci/households.html)
Q. What is a carbon sink?
A carbon sink refers to a natural or artificial ‘reservoir’ that helps to remove carbon from the atmosphere and store it. It is the opposite of a carbon source. The main natural carbon sinks are plants and oceans. Plants take carbon dioxide from the atmosphere and store the carbon in living and dead plant material and the surrounding soil. Oceans hold dissolved carbon dioxide and marine plants and animals also store and use carbon.
Q. What is carbon sequestration?
Carbon sequestration is the process of removing carbon from the atmosphere. This can be achieved through natural or artificial means.
Q. What is climate change?
Climate change is any long-term significant change in the ‘average weather’ (including average precipitation, temperature and wind patterns) of a particular region or the Earth as a whole.
Q. What is causing the acceleration of climate change?
Human activities are increasing the concentrations of greenhouse gases in the atmosphere. These gases are trapping more heat, making the Earth warmer overall.
Q. What are the potential impacts of climate change?
On average, the Earth is warming. Its temperature has already risen by around 0.7°C over the past one hundred years. The rise in temperature is expected to cause a number of impacts such as:
• Rising sea levels. A rise in the temperature of ocean waters can cause a rise in sea levels because warmer water takes up a bigger space than cooler water. Warmer temperatures can also lead to the melting of land based ice (such as glaciers and ice sheets). This means that more water is available to flow into the ocean system and cause a rise in sea levels.
• Changes in weather patterns such as more severe droughts, heat waves, floods and storms; changes in rainfall patterns; and a higher likelihood of bushfires.
• Shifting climate patterns which can have adverse impacts on plants, animals and human health. Increased temperature, changing fire regimes and more regular extreme events, such as hot and dry spells and intense rainfall will impact ecosystems, habitats, food availability and migration of species. Heat related illnesses, such as heat exhaustion, heart attacks and extreme events will impact human health.
(Source: Department of Environment, Water, Heritage and the Arts, Global Warming Cool it, http://www.environment.gov.au/settlements/gwci/households.html)
Q. What is a carbon footprint?
A carbon footprint is a measure of the impact that activities and lifestyle have on the environment in terms of the amount of greenhouse gases produced. A carbon footprint is measured in tonnes of carbon dioxide equivalent (CO2 –e) on an annual basis.
Carbon footprints can be measured for individuals, families, businesses and countries. These footprints are calculated from our direct emissions of carbon dioxide equivalent, such as the use of electricity, gas and fuel; and from indirect emissions which includes the growth, manufacturing and transport of ‘things’ we use in our lives such as food, clothes, electrical appliances and books.
On average each person in the Willoughby Local Government Area has a total (direct and indirect) carbon footprint of 25.97 tonnes of greenhouse gas pollution per year. The NSW average is 19.31 tonnes per year.
(Source: Australian Conservation Foundation Consumption Atlas, http://www.acfonline.org.au/consumptionatlas/)
Q. What can I do to reduce my greenhouse gas emissions/carbon footprint?
Top actions you can do now:
• Make the switch to purchase electricity from GreenPower (renewable energy sources e.g. solar, wind, water).
• Change your hot water system from off-peak electric to a solar hot water system with a gas booster, or a heat pump system for shaded houses.
• Manage home heating and cooling by insulating, draught-sealing and shading, while setting thermostats appropriately.
• Turn off lights, appliances and equipment when they’re not needed.
• Install energy efficient compact fluorescent light bulbs.
• Divert garden and food wastes from landfill to composting (either at home or through a Council scheme).
• Cut hot water usage by installing a water efficient showerhead, taking shorter showers and using cold water for washing clothes.
• If you have a second fridge, switch it off except when it’s really needed or consider Council’s Fridge Buyback program.
• Consider walking, cycling or using public transport instead of using the car.
• Minimise waste of packaging and materials - refuse, reduce, reuse and recycle.
Good decisions you can make in the future:
• When buying a car, consider a fuel efficient one. Alternatively, buy a transport pass, bicycle or join a car share scheme.
• When building, renovating, renting or buying a home, aim for high energy efficiency and install energy efficient appliances and lighting.
• Buy energy efficient appliances with low standby power usage (and turn standby power off when not needed).
(Source: Department of Environment, Water, Heritage and the Arts, Global Warming Cool it, http://www.environment.gov.au/settlements/gwci/actions.html)
Q. What is Willoughby City Council doing to reduce its greenhouse gas emissions?
Willoughby City Council is committed to reducing greenhouse gas emissions and assisting the community to reduce their ecological footprint through its diverse range of e.restore initiatives.
• Reducing Council’s carbon footprint: The climate change component is the single largest theme of the new e.restore program. It will organise the implementation of Council’s target of a 50 per cent reduction in its carbon footprint by 2010 through a four-stage carbon reduction strategy that involves energy conservation, renewable energy, GreenPower and carbon offsets. The projects will include an energy fund to improve energy conservation, the installation of significant renewable energy systems each year, the move to a more sustainable car fleet and Council will increase its GreenPower uptake.
• Reducing our community’s carbon footprint: The climate action campaign will also seek a substantial reduction in Willoughby’s community footprint, through green initiatives such as solar hot water systems, GreenPower and a free home assessment service. Other community programs include school initiatives and Sustainability Street. Local business programs include City Switch (energy conservation for business tenants), Sustainability Advantage (business sustainability audits) and the Cleaner Production program to reduce pollution.
Q. How can I find out more?
Phone Willoughby City Council’s customer service team on 9777 1000 or visit www.willoughby.nsw.gov.au
You can also subscribe to receive Council's free sustainability eNewsletter by visiting http://www.willoughby.nsw.gov.au/subscribe.aspx