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 What is happening in Paris this December? The governments of more than 190 nations , aimed at reducing global greenhouse gas emissions and thus avoiding the threat of dangerous climate change. Why now? 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 . 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 : 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 that led some climate sceptics to claim that the world was – – cooling.
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 What is happening in Paris this December? The governments of more than 190 nations , aimed at reducing global greenhouse gas emissions and thus avoiding the threat of dangerous climate change. Why now? 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 . 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 : 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 – – that led some climate sceptics to claim that the world was cooling.