World must aim to be fully decarbonised by 2050

Leading scientists have issued a statement as part of Earth Day 2015, highlighting the importance of action on climate change ahead of a UN conference later this year.



Today is Earth Day – an event coordinated globally as a way of honouring the Earth and demonstrating support for environmental protection. Held on 22nd April each year since 1970, it is now celebrated in 192 countries worldwide.
To coincide with Earth Day, a group of prominent scientists have issued a statement on behalf of the Earth League – an international alliance of world‐class research institutions, working to highlight some of the most pressing issues faced by humankind, as a result of climate change, depletion of natural resources, land degradation and water scarcity.
Bold action by decision-makers is required now, they claim, to pave the way for a successful agreement on carbon emissions at the UN Climate Change Conference (COP21), being held in Paris later this year. It is critically important to avoid a repeat of the disastrous Copenhagen summit of 2009.
Written by 17 world-leading scientists, the Earth Statement clarifies – in eight essential points – what the international agreement in Paris must aim to achieve to avoid dangerous tipping points of climate change. The first essential point is a commitment to limit global warming to below 2° Celsius, requiring a transition to zero-carbon societies by mid-century.
Johan Rockström, Chair of the Earth League and board member of the Global Challenges Foundation: "The window of opportunity is closing fast. We are on a trajectory that will leave our world irrevocably changed, far exceeding the 2°C mark. This gamble risks disaster for humanity with unmanageable sea-level rise, heat waves, droughts and floods. We would never consider this level of risk in any other walk of life – yet we seem prepared to take this risk with our planet. Conversely, the scientific evidence shows that we can create a positive future, but only with bold action now."
"The science, the economics and the moral imperative to protect our planet all demand this action. We are calling on policy-makers to show real leadership and commit the planet to a sustainable future," continued Rockström.
The Earth Statement warns of tipping points – thresholds in the Earth system that are difficult to reverse once crossed. It highlights recent research suggesting dramatic ice melt in parts of Antarctica may be irreversible, which provides evidence that societies need to take a precautionary approach to significantly altering the global climate.