Everything you need to know about the Paris climate summit and UN talks
As UN climate negotiations resume in Bonn, we look at why the crunch Paris climate conference from 30 November to 11 December is so important
The Guardian, 2 June 2015 (updated)
What is happening in Paris this December?
The governments of more than 190 nations will gather in Paris to discuss a possible new global agreement on climate change, aimed at reducing global greenhouse gas emissions and thus avoiding the threat of dangerous climate change.
Current commitments on greenhouse gas emissions run out in 2020, so at Paris governments are expected to produce an agreement on what happens for the decade after that at least, and potentially beyond.
Why is this important?
Scientists have warned that if greenhouse gas emissions continue to rise, we will pass the threshold beyond which global warming becomes catastrophic and irreversible. That threshold is estimated as a temperature rise of 2C above pre-industrial levels, and on current emissions trajectories we are heading for a rise of about 5C. That may not sound like much, but the temperature difference between today’s world and the last ice age was about 5C, so seemingly small changes in temperature can mean big differences for the Earth.
Why has nobody thought of getting a global agreement on this before now?
They have: global negotiations on climate change have been carrying on for more than 20 years. The history of climate change goes back much further: in the 19th century, physicists theorised about the role of greenhouse gases, chiefly carbon dioxide, in the atmosphere, and several suggested that the warming effect would increase alongside the levels of these gases in the atmosphere. But this was all theoretical.
Only in the past few decades have scientists begun the measurements necessary to establish a relationship between current carbon levels and temperatures, and the science conducted since then has consistently pointed in one direction: that rising greenhouse gas emissions, arising from our use of fossil fuels and our industries, lead to higher temperatures.
Hasn’t global warming stopped?
No. Global temperatures have been on a clear upward path. There was a spike in 1998, after which temperatures were lower – but still warmer than previous decades – that led some climate sceptics to claim that the world was cooling.
During the period since 1998, global temperatures have risen at a slower pace than they did in the previous 30 years. That, too, has been seized upon by sceptics as evidence that global warming has “paused”.
But it is important to note that temperatures have not fallen, or stalled – they have continued to rise. Given the variations that characterise our weather systems, a period in which the rate of warming slowed is not unexpected.
For the past two years, the rate of warming seems to have accelerated again, but little can be construed from that.
What progress have we seen on a global agreement?
In 1992, governments met in Rio de Janeiro and forged the United Nations Framework Convention on Climate Change. That agreement, still in force, bound governments to take action to avoid dangerous climate change, but did not specify what actions. Over the following five years, governments wrangled over what each should do, and what should be the role of developed countries versus poorer nations.
Those years of argument produced, in 1997, the Kyoto protocol. That pact required worldwide cuts in emissions of about 5%, compared with 1990 levels, by 2012, and each developed country was allotted a target on emissions reductions. But developing countries, including China, South Korea, Mexico and other rapidly emerging economies, were given no targets and allowed to increase their emissions at will.
Al Gore, then US vice-president, signed up to the protocol, but it was quickly apparent that it would never be ratified by the US Congress. Legally, the protocol could not come into force until countries representing 55% of global emissions had ratified it. With the US – then the world’s biggest emitter – on the outside, that was not going to happen.
So for most of the following decade, the Kyoto protocol remained in abeyance and global climate change negotiations ground to a near-halt. But in late 2004, Russia decided to pass the treaty – unexpectedly, and as part of a move to have its application for World Trade Organisation membership accepted by the European Union. That made up the weight needed, and the protocol finally came into force.