BREAZE

Climate Change

On this page you will find a range of information describing climate change and greenhouse gases.

The information has been collected from a number of sources including the Victorian Climate Change Program, Environment Protection Authority of Victoria, the Australian Government’s Department of Climate Change and the Victorian Government's greenhouse website. There are more sources for information at the end of this page and in the BREAZE website section: Resources.

About Climate Change (From the Victorian Climate Change Program)

Our climate is changing. Scientists and researchers have evidence that the Earth’s climate has changed over the last century. More recent evidence is telling us that most of the warming observed in the last 50 years is due to human activities and temperatures are rising faster.

The Intergovernmental Panel on Climate Change (IPCC), which advises the United Nations, is responsible for providing the international community with authoritative advice on scientific, technical and economic issues relating to climate change. The IPCC's Fourth Assessment Report (2007) concluded that climate change has accelerated in recent decades, and that most of the warming over the past 50 years can be attributed to the increase in greenhouse gas emissions from human activities.

Furthermore, scientists predict that temperatures will continue to rise in this century.

Climate change will adversely affect our environment, our communities and our economy unless we take action now - to reduce our greenhouse gas emissions, and prepare for the impacts of climate change.

What is Climate Change?

The natural greenhouse effect warms the planet and allows humans to live on the Earth. For millions of years, water vapour, carbon dioxide, methane and other greenhouse gases have occurred naturally, heating the atmosphere and making Earth habitable.

However, human activities, predominately the burning of fossil fuels, intensive agriculture and land clearing, are causing greenhouse gas concentrations to rise above natural levels, further heating the planet. This is called the enhanced greenhouse effect.

As the concentrations of these gases in the lower atmosphere grows, global temperatures rise, causing changes to weather conditions worldwide. The enhanced greenhouse effect is often referred to as global warming or climate change.

We need to reduce greenhouse gas emissions

Throughout history, the Earth’s climate has fluctuated naturally– from seasonal variations to sweeping shifts on geological time-scales, like ice ages. However, climate change currently occurring is linked to the build-up of greenhouse gases in the atmosphere from human activity.

Atmospheric concentrations of carbon dioxide, a key greenhouse gas are higher now than at any time in the last 420,000 years. These raised levels correspond closely to changes in fossil fuel burning and land clearance.

Emissions of greenhouse gases have risen due to increasing demands for energy, associated with industrialisation and growing populations, and as a result of changing land use and human settlement patterns.

Greenhouse gas emissions

A summary of Victoria's greenhouse gas inventory can be found on the Victorian Climate Change Program website, Click here.

Australia’s emissions

Australia generates approximately 576 Mt CO2 equivalent emissions each year. Australia’s per capita emissions are nearly twice the OECD average and more than four times the world average. Click here for more information about our total national and per sector emissions.

The per person emissions in Australia are approximately 28.6 tonnes CO2e (Carbon Dioxide equivalent), if exports are included, or 21.9 CO2e if exports are excluded.

Significantly:
Travel amounts to about 17% of emissions, but frequent flyers will have considerably larger emissions due to air travel.

Electricity, natural gas, LPG and other fuels combine to make 16% of total per person emissions, with the majority being electricity.

The single largest component of total emissions, at 35%, is the indirect emissions associated with food, provision of shelter and essential goods

Purchases of large goods such as cars and recreation equipment (boats, caravans, sporting goods etc) account for 6% other goods and services in general are another major category at 19%, with the remaining 5% emissions due to government activities.

We also know that current trends in household energy use tend to encourage greater energy use. Read more about Australia's annual per person emissions.

Ballarat's Emissions

Total emissions for the Ballarat region are 1,442,000 tonnes (1.44Mt CO2e); and consist broadly of 60% from electricity generation and use, 12% from gas use and 28% from transport.

Download the full report here

Impacts of Climate Change

A majority of the world's scientists agree that human activities have resulted in observed increase in global average temperatures, particularly since the middle of the 20th century.

Recent data indicates that the global mean temperature has increased by between 0.2 and 0.6°C since the late 19th century, while Australian average temperatures have increased by 0.8°C.

Earth's average temperature might increase by up to between 6 – 9°C over the next 100 years, if greenhouse gas concentrations continue to increase.

As the average global temperature rises, it will lead to other changes in weather. Storm patterns and severity might increase, sea levels will rise, and floods and drought may become more frequent and more severe.

Some changes to the climate are inevitable – even if we stop emitting greenhouse gases now, the gases we have already released will have an effect. However, we must do everything we can to avoid further changes and to adapt to the impacts of climate change.

The scientific consensus

The Intergovernmental Panel on Climate Change (IPCC) was established by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) to assess scientific, technical and socio-economic information relevant for the understanding of climate change, its potential impacts and options for adaptation and mitigation.

The IPCC's Fourth Assessment Report (2007) concludes that global warming has accelerated in recent decades, and there is new and stronger evidence that warming over the past 50 years is attributable to the increase in greenhouse gas emissions associated with human activities. Visit the IPCC website.

What is the greenhouse effect? (From EPA Victoria)

A car parked in the sun feels warmer inside than the outside air. The car windows allow the sun's light energy to enter the car, where it is converted to heat energy. Glass windows do not allow heat energy to pass through as easily as light, so some heat is trapped in the car, raising its temperature. This is an example of a greenhouse effect.

In Europe greenhouses are used to capture the sun's heat, especially in the northern latitudes, where not enough sunlight and warmth occurs to grow some plants. Greenhouses are mostly made of glass, and they get that name because of the lush greenery that can be produced inside them at the right time of year – and which would not normally appear in that part of the world.

The Earth is covered by a blanket of gases which, like the car window allows light energy from the sun to pass through to the Earth's surface, where it is converted to heat energy. Some of this heat energy is trapped by gases in the atmosphere as it tries to escape back into space. This keeps the Earth and us warm. The gases which trap heat are called greenhouse gases.

The Earth's atmosphere is made up of 78% nitrogen and 21% oxygen. Less than 1% of the atmosphere is greenhouse gases, however this small amount can make a big difference.

Human activity is generating more greenhouse gases (mainly carbon dioxide, methane, nitrous oxide and halocarbons) which are trapping more heat. It is widely accepted that increasing the concentrations of these greenhouse gases is leading to an increase in the world's average temperature, and climate scientists have now concluded that the rising temperatures will affect the environment, and hence humans, plants and animals, in a number of ways. These impacts are predicted to include the melting of polar ice caps, rising sea levels, increasing intensity and frequency of storms, and changes to weather patterns that will alter agricultural productivity as well as affecting snowfall and associated recreational and tourism activities.

Further information about the greenhouse effect is available from the Victorian Government's greenhouse website.

Greenhouse gases

Water vapour is the most common greenhouse gas. However, three other main greenhouse gases contribute to human-induced climate change:

Carbon dioxide (CO2) is released into the atmosphere by plants and animals. However, human activities, like burning fossil fuels, are increasing atmospheric concentrations beyond natural limits. CO2 is the main contributor to climate change, and accounts for about two thirds of greenhouse gases produced by human activities. Photosynthesis in plants removes CO2 from the atmosphere.

Methane (CH4) is not as abundant as CO2, but is 21 times more effective at trapping heat. It is released when vegetation decomposes in oxygen-free environments (such as a fire or landfill), as well as from animal digestive processes.

Nitrous oxide (N2O) occurs naturally in the environment, but human activities increase its atmospheric concentrations. This gas is most often released when chemical fertilisers and manure are used in agriculture.

For purposes of measurement, all greenhouse gases are converted to a common unit, called CO2 equivalent (CO2e).

Additional resources

The Victorian Climate Change Program provides links to other websites and resources that can help you understand climate change and the enhanced greenhouse effect. Click here.

EPA Victoria also provides an overview of current climate change terminology, click here.