Climate Change in a nutshell
Greenhouse gases in our atmosphere act like a blanket and trap heat at the surface giving us an average global temperature of 10°C - without them the Earth would be a chilly -15°C.
Climate change is being caused by elevated levels of greenhouse gases, the main culprit being Carbon Dioxide (CO²). This gas is released whenever we burn fossil fuels in our homes, cars, factories and power stations. Normally CO² is absorbed by plants and oceans but we are adding it so fast that concentration levels have risen 35% since 1900.
The result so far is an observed rise in global average temperature of 0.8°C over the last century with a further 1°C rise already “in the pipeline”. On current trends the high temperatures of the 2003 European heat wave, which, according to official figures, killed 14,800 people in France alone, will be normal by 2050 and cool by 2060!
What scientists fear most, however, is that if temperatures increase by more than 2°C above pre-industrial levels positive feedbacks within the climate system could cause a runaway effect.
To keep below this danger level the latest IPCC report warns that emissions need to be reduced by 50% to
85% by 2050. Given that 84% of the energy we consume is derived from fossil fuels that is a tall order.
Drawing the curtain on Fossil Fuels
Before the era of fossil fuels humanity was constrained by the limited yearly supply of food and energy that could be harvested from nature. The discovery of oil, coal and gas lifted that constraint and enabled civilisation to develop to where it is today.
But fossil fuels buried within the Earth’s crust are finite and are depleting at an alarming rate. For example, geologists warn that world oil discovery peaked in the ‘60’s and now stands at 1 barrel discovered for every 4 consumed. At current rates of consumption world petroleum reserves will be exhausted within 35 years.
However, the most interesting point is that if we are to prevent climate change we must leave much of the remaining oil, coal and gas in the ground let alone begin extracting unconventional fossil fuels such as tar sands, shale and ocean bed methane deposits. To exploit these resources would be to commit “ecocide”.
Grey clouds with silver linings
What all this means is that our present carbon based society is unsustainable and will destroy the environment. We must draw the curtain on this era and learn to live again within nature’s limits. This will mean a powering down of our economies and a rapid descent from our current energy intensive way of life.
Although making this transition is a daunting challenge it offers humanity a unique opportunity to embrace a cleaner more sustainable lifestyle. Whatever happens, as we combat global warming and reduce our consumption of fossil fuels we will increasingly depend on locally produced food, goods, services and energy sources. This shift could act as a force for positive change and enable communities in Ireland and around the world to strengthen and become self reliant.