The recent survey commissioned by Sustainability Victoria came up with the startling statistic that more than 70% of Gippslanders consider that climate change is at least partly the result of natural causes. More so 11% think the warming is entirely natural. Locally, East Gippsland Shire Councillor Ben Buckley has espoused this cause for some time. But it is a recipe for inaction and both Ben and the majority of Gippslanders are in this instance wrong.
The evidence for global warming is overwhelming. A recent US government report measured 9 different indicators of this including warming oceans, land and sea surface temperatures and sea level rise. The evidence in turn came from 28 different databases. See here. This warming is directly the response of humanity burning fossil fuels on an increasingly grand scale since the industrial revolution.
How do we know this? The basic physics of the greenhouse effect tells us that if we increase greenhouse gases in the atmosphere the planet will warm. The steady increase of these gases has been measured for more than 50 years. Testing of the carbon isotopes in the atmosphere indicates combustion of fossil fuel origin – verifying the obvious.
Could the basic physics be wrong? Most unlikely. The theory of the greenhouse effect is approaching 200 years of age. More carbon dioxide in the atmosphere increasing the planet’s temperature (scientists use the term ‘climate forcing’) has been known for 120 years. The greenhouse effect has stood the test of time.
Natural change implies that the planet is heating up from increased radiation from the sun, either by increased activity in the sun or by some small alteration in the earth’s inclination or rotation. It should be mentioned that the warming (or cooling) engendered by these natural changes takes place over long periods – in geological time. The warming we are currently experiencing by comparison is taking place in an instant on this time scale.
Satellite measurements prove that extra radiation from the sun is not the cause of our current global warming. If the source of the extra energy was from the sun the upper atmosphere (Stratosphere) should be warming. In fact it is cooling. As the graph above indicates the energy from the sun has shown a slight cooling this century. The conclusion from this is that planet should be cooling. More details on this can be found here.
The message is clear. Climate change is a threat to human existence. It is a threat we have caused ourselves. We must therefore act now on as many fronts as possible. In Gippsland that initially means a rapid (and just) transition from coal fired power plants and destructive logging to renewable energy and other sustainable practices.