We're All In This Together
The Age
Monday June 4, 2007
Ben Haywood gives an overview of the climate-change issue.
What is climate change?CLIMATE change is one of the biggest issues facing the planet, but the principles behind it aren't that complicated.Basically, the world is getting warmer.According to the Bureau of Meteorology, Australian temperatures have increased, on average, by about 1 degree since the 1950s.This global warming is believed to be causing broader changes to the planet's climate. The BOM says the world is experiencing rapid climate change.In Australia over the past 60 years, the frequency of heatwaves has increased and the number of frosts and cold days has decreased.The north-west of the country has had increased rainfall and the far south-west has experienced a decline.The world's climate goes through natural cycles, but there is growing evidence that these increasingly rapid changes are the result of human activity.The rate of warming in the 20th century is unprecedented in at least the past 10,000 years.CLIMATE VS WEATHER Weather is the condition of the atmosphere at any given moment - the temperature, the wind, the rainfall, the cloud cover. It changes from moment to moment and place to place, sometimes very dramatically.The climate is generally a much more stable thing, based on long-term averages in weather. It is measured over many years.Climate data is what allows us to predict that this time next year is likely to be similar to today.What is causing climate change?MODERN climate change is being caused by an increase of greenhouse gases in the atmosphere.Our planet is like a giant greenhouse.Gases in our atmosphere such as carbon dioxide and methane (greenhouse gases), work to trap the sun's heat and keep the Earth warm. Too little of these gases and the Earth chills. Too much and it overheats.Unfortunately, human activity is increasing the amount of greenhouse gases in the atmosphere, enhancing the greenhouse effect.Eighty per cent of the world's energy comes from burning greenhouse-gas-producing fossil fuels. In Australia, electricity production is the biggest cause of greenhouse gas pollution, followed by transport.A few scientists challenge the prevailing view that humans are the cause of this rapid climate change. Some argue that this is merely part of the planet's natural climatic cycle, or other naturally occurring processes, and can't be stopped. Others say the real cause of global warming is unknown and some dispute the accuracy of climate records. These views have been discredited by the bulk of the scientific community.The world is taking the threat of climate change seriously, however, and looking at ways to reduce human impact on the climate.GREENHOUSE EFFECT The greenhouse effect is a natural process that is central to the survival of life on Earth. Sunlight passes through the atmosphere and warms the Earth's surface.The land and oceans then release this heat (infrared radiation) into the atmosphere.Naturally occurring greenhouse gases, such as water vapour and carbon dioxide, absorb some of this energy, warming the lower atmosphere.Without the greenhouse effect the average global surface temperature would be minus 18 degrees rather than the current average of 15 degrees.Source: CSIRO What are the threats of climate change?ACCORDING to the Intergovernmental Panel on Climate Change, by 2100, average world temperatures are likely to be between 1.4 degrees and 5.8 degrees higher than they were in 1990.Although the temperature change seems small, the Earth's ecology is fragile and many already endangered species will be further threatened. Polar bears, sea turtles, many frog species and the North Atlantic right whale are among those most at risk.Sea levels will also rise. According to the CSIRO, by 2001 the global average sea level will be between nine centimetres and 88 centimetres higher than 1990 levels. As the Earth's atmosphere warms, so do the upper layers of the oceans. As water heats, it expands, causing the sea level to rise.Scientists also predict an increase in the frequency and duration of more extreme weather events such as heavy rains, droughts and floods.This will have an impact on the infrastructure of cities. A CSIRO report, Infrastructure and Climate Change Risk Assessment for Victoria, prepared for the State Government identified a number of risks from climate change.They include worsening water shortages as temperatures climb and rainfall is reduced, and damage to infrastructure from extreme weather.PAGES 10-15: The impact of climate change on the world's eco-systems What is the world doing about climate change?THERE are a number of world bodies working to cut emissions and address the problem of climate change on a global level.??Intergovernmental Panel on Climate Change (IPCC). Formed in 1988 by the World Meteorological Organisation and the United Nations Environment Programme, the role of the IPCC is to use information from around the world to constantly assess the risk of climate change, options for adapting to it and stopping it.??United Nations Framework Convention on Climate Change. This international treaty came in to force in 1994 with nearly universal support (191 countries have ratified the treaty). It set out an overall framework for world governments to work together to address climate change. The 1997 Kyoto Protocol was an important amendment to this treaty, setting targets for a reduction in global greenhouse gas emissions.The issue of climate change is also high on the agenda at other major world meetings including the G8 and APEC.In spite of the fears of irreversible climate change and world efforts to cut emissions, global carbon dioxide emissions are still on the rise - and at an increasing rate.A report last month in a prestigious US science journal showed that between 2000 and 2004, the rate of increase in global carbon dioxide emissions from fossil fuels was three times greater than in the 1990s.The increase in emissions has been attributed to increasing populations, growing global wealth and greater than expected use of fossil fuels.A report released to the Federal Government last week recommended that Australia commence carbon emissions trading by 2012.Opposition leader Kevin Rudd has pledged to launch a similar scheme by 2010, and set a long-term emissions reduction target of 60 per cent on 2000 levels by 2050.PAGE 6: What schools around the world are doing to save the environment THE KYOTO PROTOCOL The Kyoto Protocol is an international agreement that was negotiated in 1997 to reduce global greenhouse gas emissions.It set a global target to reduce annual world emissions to 5.2 per cent below the 1990 level between 2008 and 2012.As of May this year, 172 countries had ratified the protocol, accounting for more than 60 per cent of the world's greenhouse gas emissions.Australia and the United States the US alone is responsible for 25 per cent of global emissions) are the only developed countries that have refused to ratify the treaty.The Howard Government argues that signing the treaty is not in Australia's interests. Prime Minister John Howard says that the treaty would put Australian jobs at risk by subjecting our industries to restrictions that other major polluters such as China, India and Indonesia do not face.Last month, 75 professors of economics called on the Federal Government to ratify the protocol without delay, warning of the economic damage that could be done to Australia if it fails to reduce greenhouse gas emissions.Opposition leader Kevin Rudd has pledged to ratify the Kyoto Protocol if he is elected to government at this year's federal election.WORST OFFENDERS Australia is the second worst carbon polluter in the world, releasing 19 tonnes of carbon dioxide per person from fossil fuels each year. Only the US is worse at 20 tonnes year per capita. The global average is 4.3 tonnes per person.Australia's emissions from fossil fuels are also growing faster than the global average at twice the rate of the US.Victoria and the other Australian states and territories have committed to starting a national emissions trading scheme by 2010.LinksIPCCwww.ipcc.chUNFCCCunfccc.intCSIRO - Climate & Weathercsiro.au/csiro/channel/ich3h.htmlBureau of Meteorology- Climate Changewww.bom.gov.au/climate/change/Victorian Government Greenhouse websitewww.greenhouse.vic.gov.au
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