Setting The Scene for Global Warming

We now know that the climate of the planet we all depend upon for survival is changing, and that the earth is warming at a rate unprecedented in recorded history.

Human activities have been altering the composition of the atmosphere, changing the balance of how much solar energy is trapped, and how much is reflected away from the earth. Burning fossil fuels has increased atmospheric concentrations of greenhouse gases such that current concentrations are the highest for the last 650,000 years.

During the past 100 years, global average surface temperatures have increased by about 0.7˚C. The future we face is one of further warming, changes to rainfall, sea level rises, and increasing frequency of natural disasters.

There is evidence that this is already having an adverse impact on human health and will continue to do so in complex ways, which we are only beginning to understand. We must take action now to both prevent worsening of the problem and adapt to a range of impacts now and into the future.

‘Most of the observed increase in globally averaged temperatures since the mid-20th
century is very likely due to the observed increase in greenhouse gas concentrations.’

Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report 2007.

Over the next century, a global warming of 1.1–6.4˚C is predicted. History has shown that a warming of 1–2˚C can have dramatic consequences. Even the amount of warming
to date has been associated with increasing heatwaves and floods, more intense droughts, retreat of glaciers, sea level rise, coral bleaching and disruption to ecosystems.

Once carbon dioxide is released into the atmosphere, it remains there for 50 to 200 years. Regardless of how well we manage to curb greenhouse emissions, some degree of climate change is inevitable and we will be forced to deal with the evolving impacts for many generations to come.

The Australian government has commissioned studies which revealed that Australia’s average surface temperatures have increased by approximately 0.9˚C from 1910 to 2002,
with most of the change occurring since 1950. Projections for Australia are for water security problems tointensify with more frequent and intense droughts, increases in the severity and frequency of storms and coastal flooding, heatwaves and fires, significant loss of biodiversity, risks to major infrastructure, more blackouts, a decline in agriculture and forestry production. Many ecosystems in Australia are likely to be lost or severely damaged, with temperature increases of 1–2˚C, including the Great Barrier Reef, Kakadu, alpine zones and World Heritage rainforest areas.

So what needs to happen? Many many things, but as the research unfolds one thing is for certain. We are dealing with a global problem at a local level. What is your government doing to keep afront of this worldwide phenomenon?