Since the start of the industrial revolution, mainly as a result of humans using fossil fuels (coal, oil and gas), the level of carbon dioxide in the atmosphere has increased from about 280 parts per million to about 400 parts per million, a level not seen for a million years or more, and growing at an extraordinarily rapid rate.
This has led to increasing destabilizations of the planet’s energy, temperature and climate systems. For the last 10,000 years, following the exit out of the last ice age, the Earth’s climate has been remarkably mild and stable, the surface temperature not increasing or decreasing by more than 0.5C. Within the 21st Century, in the absence of stringent global control of greenhouse gas emissions, CO2 emissions in the Earth’s surface temperature could climb as much as 4.5C above that 10,000 year average.
These are unchartered waters: both the present change and the rate of change in atmospheric carbon dioxide are leading scientists to regard our predicament as ominous. They warn that we are heading the Earth system toward tipping points beyond which recovery by human actions will not be possible.
The response so far.
” For the sixth year running, the global economy has missed the decarbonisation target needed to limit global warming to 2 ̊C. Confronted with the challenge in 2013 of decarbonising at 6% a year, we managed only 1.2%. To avoid two degrees of warming, the global economy now needs to decarbonise at 6.2% a year, more than five times faster than the current rate, every year from now till 2100. On our current burn rate we blow our carbon budget by 2034, sixty six years ahead of schedule. This trajectory, based on IPCC data, takes us to four degrees of warming by the end of the century.”
Leo Johnson, Partner, Sustainability and Climate Change, PricewaterhouseCoopers. Two degrees of separation: ambition and reality. September 2014.
“The IPCC has warned that our current trajectory will lead to warming estimated to range from 3.7 – 4.8°C over the 21st century. It anticipates severe adverse impacts on people and ecosystems through water stress, food security threats, coastal inundation, extreme weather events, ecosystem shifts and species extinction on land and sea. At the higher levels of warming, the IPCC states that these impacts are likely to be pervasive, systemic, and irreversible”.
Leo Johnson from the same report.
The news from Lima.
The recent intergovernmental meeting in Lima was intended to lay down a clear path leading to the Paris conference in December 2015. Instead it left observers worried that the necessary de-carbonisation at 6.2% a year will not be achieved in Paris.
This is a poem that brilliantly illustrates the unfruitful situation we’re in with the international climate talks.
“Perhaps the biggest challenge is that governments are unlikely to outline cuts in annual emissions that will be collectively consistent with a path that gives a good chance of remaining below the 2C danger limit”.
Professor Lord Stern of Brentford, Chair, Grantham Research Institute on Climate Change and the Environment at the London School of Economics and Political Science and President of the British Academy. The Guardian Monday 15th December 2014
It is clear that – to put it mildly – we cannot be certain that inter-governmental negotiations will bring about de-carbonisation on a sufficient level to prevent uncontrollable climate change.by