Global warming
What is global warming?
Global warming refers to the increase in the average temperature of the Earth's atmosphere and oceans in recent decades as measured by scientists. Even what seem like quite small changes in temperature can have massive effects on the environment. Think about how little your body temperature has to rise for you to feel unwell - one degree celsius can make all the difference.
The increase in global temperatures has knock-on effects, including a rising sea level and changes in where, when and how often it rains. The frequency of extreme weather events, such as floods, droughts, heat waves, hurricanes, and tornados is affected by climate change.
It is widely accepted in the scientific community that most of the climate change in the world over the last 50 years has been caused by human activity. One of those activities is the creation of greenhouse gases, like carbon dioxide emitted by burning fossil fuels.
Greenhouse gases are a little like the one-way glass you see in police dramas on TV. They allow heat from the sun to pass freely through the atmosphere to the Earth's surface as they always have. What has changed is that these gases absorb some of the heat that would otherwise bounce back from the Earth's surface into space. This makes it harder for the Earth to cool.
About 75 per cent of the carbon dioxide emissions release by human activity in the past 20 years has come from fossil fuel burning.
What is being done?
Now that we understand some of the factors causing global warming, humans are trying to reduce their impact on the environment. One way of doing this is to reduce the amount of carbon dioxide released into the atmosphere. This is done by using fossil fuels more efficiently and making better use of renewable energy sources.
In Australia, the Federal Government has regulations in place that promote the use of renewable energy sources. In NSW we have legislation governing greenhouse gas emissions. The NSW legislation is some of the most advanced in the world.
What about the rest of the world?
Our efforts in NSW and Australia are part of a global effort to deal with the problem of global warming. Elsewhere, over 160 countries have now agreed to the Kyoto Protocol, which is a United Nations agreement on climate control.
The protocol is a complicated agreement that commits the countries who agree to it to cut their greenhouse gas emissions.
Australia has not signed the Kyoto Protocol but the NSW Greenhouse Gas Abatement Scheme incorporates many of its principals.