About Climate Change
The climate is changing and the issue is here to stay. Demand for electricity and heat, the creation of waste, agriculture, and land use change are increasing greenhouse gasses (GHGs) in the atmosphere. This is now at a concentration substantially higher then at any other time during the last 750,000 years.
These gasses are altering the earth’s energy balance, causing an overall warming and a more energised weather system, leading to climate change. Although the climate fluctuates naturally, the 0.74oC rise in global temperatures measured over the last century is larger than can be accounted for by natural factors alone. The current scientific consensus is that human factors are very likely the cause of global warming, meaning a 90% or greater probability.
To avoid dangerous climate change the temperature increase must be stabilised at no more then 2oC, which is only 50% likely if GHG concentrations in the atmosphere top 450ppm. Currently GHG concentrations are 400ppm and rising. This is a lower GHG concentration threshold then previously calculated and as a result governments are being pressured to increase GHG reduction targets and toughen measures to meet them.
In October 2006 Nicholas Stern, the UK government’s Chief Economist, reported that climate change represents the greatest and widest ranging market failure ever seen, but there is still time to avoid the worst impacts of climate change if we act now, at a cost of 1% global GDP to avoid potential costs of 20% global GDP. This was echoed by the Intergovernmental Panel on Climate Change’s fourth assessment report which reached a consensus that the benefits of mitigating climate change were worth the costs.
The situation is urgent but not hopeless, as Al Gore states in An Inconvenient Truth; “we landed on the moon – one of the most inspiring examples of what we can do when we put our minds to it”. The ozone hole is closing as a result of global effort, and we can still avoid the worst climate change if we act now and move to a global low carbon economy.