Special Alert: IPCC releases latest climate science report


The most exhaustive and authoritative climate study ever shows with extreme certainty that climate change is real, caused by human activity and requires urgent action. Global sea levels are rising, precipitation patterns are changing, sea ice is declining and oceans are acidifying – all with grave consequences for our communities, environments and economies. These are the conclusions from the Nobel Prize winning Intergovernmental Panel on Climate Change (IPCC) who launched their landmark report, having had their major findings signed-off by governments from around the world. It is now clearer than ever that the warming of the entire climate system is “unequivocal” and that humans emitting greenhouse gases is the “dominant” cause, prompting civil society groups to pronounce the debate around climate science over. At the launch it was clear that scientists are concerned with existing policies we are currently on track to exceed the internationally agreed warming limit of 2°C. Lord Stern, former chief economist of the World Bank, says that to have at least a 50% chance of keeping within that so-called safety limit, we must emit no more than 820-1445 billion tonnes of greenhouse gases during this century, but at present emissions rates we are set to break this carbon budget in just 15 years; sending us into dangerous and uncharted territory. The IPCC conclusions have triggered a wave of calls from global leaders, including UN Secretary General Ban Ki-moon, to urgently address the political blockage that is slowing down action to tackle climate change. Many are keen to emphasise the huge benefits of addressing the climate risk that include energy security, new jobs and stable food supplies.


  • MT ‏@lflorez The 5 most important – and sobering – charts from the #IPCC report http://bit.ly/198s5G4 #climate


  • Hashtags to use: #debateisover, #IPCC, #AR5, #IPCCAR5
  • Campaign to sign: the BIG fix (Avaaz)

Key Points

Top line messages:

The Science

  •  The IPCC Report shows with extreme certainty that climate change is real, caused by human activity and requires urgent action. According to the IPCC, sea levels are rising, precipitation patterns are changing, sea ice is declining and oceans are acidifying – all with grave consequences for our communities, environments and economies. Some regions of the world will experience more frequent or more intense droughts, floods or storms.
  •  If we look at global warming, the three most recent decades have all been warmer than all preceding decades since the industrial revolution. The period covering 1983 – 2012 was very likely the warmest 30-year period in 800 years, and likely the warmest of the past 1400 years.
  •  This is the most comprehensive, authoritative and scrutinized report on climate change that has ever been written. Prepared by over 800 of the world’s leading experts from all corners of the globe it is the most encompassing assessment of scientific knowledge on climate change.

What it means

  • Climate change is impacting people here and now, but the consequences will be even worse in the future if action is not taken. Therefore the focus must now be on ensuring comprehensive government action that averts the worst impacts of climate change.
  • For the first time, the IPCC report identifies a global level for carbon dioxide emissions that the world cannot exceed if we are to meet the international goal of preventing devastating levels of global warming. While the new IPCC report comes with good news saying that strong action can still keep warming within the 2 degrees C danger-threshold, it also states clearly that the world is currently headed for a much higher temperature rise.
  • Governments must urgently implement plans to reduce emissions or the dangerous impacts already affecting vulnerable communities will become even more widespread.

Urgent Action 

  • Governments must make necessary funding available to increase resilience and support vulnerable communities suffering the most from the impacts of climate change happening now. More funding would be available if governments phased out inefficient fossil fuel subsidies and instead provided incentives for and access to clean, renewable energy for all.
  • Most known fossil fuel reserves must stay in the ground if we want to guarantee a safe climate future, so governments should divert investments from new fossil fuel development towards clean, renewable energy and innovative solutions to use energy more efficiently. The solutions exist and taking action makes sense, delivering important benefits for communities, economies and the environment they depend on.

Managing Risk

  •  Climate action is also about risk-management. The science tells us that that risks are huge, and our actions have to match what is effectively the biggest challenge of our generation.
  • Climate action is necessary to stave off this challenge, and to create a fairer, healthier and happier place for future generations. The longer we delay real action, the more expensive addressing climate change will get.



The IPCC’s full technical report from Working Group 1 that includes information on climate change at the regional scale. If you are interested in local climate observations, projections and impacts affecting your region directly and want to make your messaging more relevant and engaging in your country, we have produced a “Region by Region” Guide to IPCC’s AR5 WG1.

The IPCC release is an opportunity to reiterate and reinforce findings from important new climate science that has been published in recent months (some of it being reflected in AR5, other research published after the AR5 cut off point), which strengthens both our understanding of climate change and its impacts. We have put together a useful summary for talking about climate science around the AR5 report launch.



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Key Quotes

  • “This new report will be essential for governments as they work to finalise an ambitious legal agreement on climate change in 2015. To add momentum to this process, I will convene a climate summit in September 2014 at the highest level. The heat is on. Now we must act.” – UN Secretary General, Ban Ki-Moon
  • “Observations of changes in the climate system are based on multiple lines of independent evidence. Our assessment of the science finds that the atmosphere and ocean have warmed, the amount of snow and ice has diminished, the global mean sea level has risen and the concentrations of greenhouse gases have increased.” – Qin Dahe, Co-Chair of IPCC Working Group I
  • “Continued emissions of greenhouse gases will cause further warming and changes in all components of the climate system. Limiting climate change will require substantial and sustained reductions of greenhouse gas emissions. Global surface temperature change for the end of the 21st century is projected to be likely to exceed 1.5°C relative to 1850 to 1900 in all but the lowest scenario considered, and likely to exceed 2°C for the two high scenarios. Heat waves are very likely to occur more frequently and last longer. As the Earth warms, we expect to see currently wet regions receiving more rainfall, and dry regions receiving less, although there will be exceptions.” – Thomas Stocker, Co-Chair of Working Group I
  • “We have gone a long way in the last 25 years in our knowledge of the climate system and the human role in climate change. [The report] should serve for yet another wake-up call that our activities today will have a profound impact on society, not only for us, but for many generations to come. Many of the extremes of the last decade were unprecedented. The IPCC report demonstrates that we must greatly reduce global emissions in order to avoid the worst effects of climate change.” – Michel Jarraud, secretary general of the World Meteorological Organisation
  • “I think it’s interesting to look at this in the context of the whole series of IPCC assessments that have come out. We’re now on the fifth one and over time the message that has become stronger and stronger that there is a measurable human impact on climate …The message hasn’t changed, it’s just being delivered with greater and greater confidence as the evidence base has accumulated.” – Dr John King from the British Antarctic Survey
  • “Traditionally, we always see surface temperature as our key metric of climate change … [This report] includes a greater understanding of the climate system as a whole and the realisation that its not just about surface temperature, there are so many other metrics that show evidence of change … This report does paint a more complete picture than ever before.” – Dr Kate Willett from the Met Office
  • “Given that we are currently emitting 50bn tonnes of emissions every year, even if we stay at today’s levels we will use up our entire budget in 15 to 25 years. And if we carry on increasing annual emissions at the present rate, we will exhaust it even quicker. The report reveals clearly how slow, weak action increases the risks because greenhouse gases continue to accumulate in the atmosphere, and the installation of long-lasting high-carbon capital and infrastructure locks in future emissions. It is this brutal arithmetic that should persuade companies, communities, cities and nations to seize the opportunities for sustained and sustainable growth offered by hastening their transition to a low-carbon economy.” – Lord Nicholas Stern
  • “Climate change is a long term challenge but one that requires urgent action, not tomorrow but today and right now, given the pace and the scale by which greenhouse gases are accumulating in the atmosphere and the rising risks of a more than 2 degree C temperature rise. For those who want to focus on the scientific question marks, that is their right do so. But today we need to focus on the fundamentals and on the actions. Otherwise the risks we run will get higher with every year. A universal new UN climate agreement by 2015 is critical, backed by supportive voluntary initiatives such as those managing down short-lived climate pollutants like black carbon. As work under the inclusive Green Economy shows, the benefits of a transition to a low carbon future are multiple from improved public health, food security and job generation to combating climate change now and for future generations. – UN Under Secretary General and UNEP Executive Director Achim Steiner
  • “For governments, businesses and investors to take action to create a prosperous low carbon economy, they need the facts. And now we have them, in the form of the first volume of the IPCC report. We now have greater levels of confidence that the global economy is responsible for the warming the world is experiencing – and we know that each decade’s average temperatures continue to rise. We also know, thanks to the new report, that the observed impacts of the limited warming we have experienced to date are faster and deeper than previously expected. These impacts are already being experienced by key economies, and HSBC’s latest research identifies India, China, Indonesia, South Africa and Brazil as the five G20 nations most vulnerable to the impacts of climate change. Together, they represent 31% of projected global GDP in 2050. Over the following year, we believe that – from the next reports – the IPCC will provide stronger foundations for climate action by governments, businesses and investors, culminating in the deadline for negotiations in December 2015.” – Nick Robbins, head of HSBC Climate Change Centre for Excellence
  • “Today’s IPCC report tells us that we’ve already exceeded half of the carbon budget available before we reach the point of emergency. This means that we must address climate change now, and that we need to stop burning fossil fuels. The report matters across industries.” – Mindy Lubber, president of Ceres
  • “One thing is for sure: denial and procrastination are no longer options, whether for governments or the private sector. The new IPCC report concludes that there is 95 percent certainty that human activity — such as the burning of fossil fuels — is the primary cause of climate change. If you were 95 percent certain that thieves would break into your home or factory tonight, you wouldn’t wait till tomorrow to take precautions. If a vaccine were 95 percent certain to have disastrous side effects, governments wouldn’t require years of fruitless discussion before pulling it off the market. So how much certainty do we need before policymakers wake up and finally face the threat of climate change?” – Yvo de Boer, Special Global Advisor on Climate Change and Sustainability to KPMG International
  • “The latest climate science affirms what small scale farmers around the world are telling us, seasons are changing, weather is increasingly extreme and unpredictable making it tougher to feed their families. This report also tells us it is possible to avoid the very worst impacts of climate change and the goal of ensuring everyone has enough to eat is still attainable. Governments should learn from the mistakes of the global financial crisis where warning signs were ignored and listen to the experts before it is too late. They must take actions immediately to slash emissions as well as investing in building the resilience of people in poverty so we can move from the current path facing disaster to higher safer ground.” – Tim Gore, Oxfam’s Grow Campaign Head of Policy
  • “The debate about responsibility for climate change is over. Scientists are more certain than ever that humans are causing climate change but fortunately, equally certain that we still have the time and means to fix it. What we need now is for all 28 EU delegates that signed off on this report to take this mandate back to their capitals and urge their governments to take immediate climate action. We don’t want to see another comprehensive report on the grim realities of climate change gathering dust on politicians’ bookshelves while impacts mount. The risk of catastrophic effects from malnutrition, food conflicts, wildfires, floods and extinctions is too great to impose upon the people and nature of Europe.” – Wendel Trio, Director of Climate Action Network Europe
  • “We’ve won the scientific argument for fifteen years–we know beyond any doubt that carbon is warming the atmosphere. But we also know beyond any doubt that fossil fuel money is polluting the politics of climate. That’s why we keep building movements.” – Bill McKibben, co-founder of 350.org
  • “The report shows that there is more clarity about human-generated climate change than ever before. We know that the total effort to limit warming does not add up to what is needed to bend the emissions curve. To steer humanity out of the high danger zone, governments must step up immediate climate action and craft an agreement in 2015 that helps to scale up and speed up the global response. As the results from the latest and best available science become clearer, the challenge becomes more daunting, but simultaneously the solutions become more apparent. These opportunities need to be grasped across society in mutually reinforcing ways by governments at all levels, by corporations, by civil society and by individuals.” – UNFCCC Executive Secretary Christiana Figueres
  • “The IPCC report sets out more clearly than ever that climate change is happening right here right now, that it is primarily caused by man-made greenhouse gas emissions and that it is having a serious impact on the planet and its people. As a global organisation working to tackle poverty in some of the world’s poorest places, we know that climate change is now one of the greatest threats to achieving poverty reduction today and in the future. Climate change impact are also hitting rich countries hard, including the US, Australia and Europe. The risks of inaction to tackle its causes and effects are too great to ignore.” – Sven Harmeling, CARE’s climate change advocacy coordinator
  • “The IPCC’s findings reflect exactly what we are seeing in the ocean: massive changes in the distribution of marine organisms and marine ecosystems globally. The IPCC”s focus on the ocean is long overdue and begins to reveal the extraordinary extent to which this critical Earth System is being impacted by climate change. There is no good news and no reason for optimism as our ocean continues to take the brunt of carbon absorption. The combination of acidification, warming and deoxygenation that we are seeing – the so-called ‘deadly trio’ is unprecedented in the carbon record. It poses a serious threat not just to the ocean but to the Earth system services it supports and there can be no stronger imperative for action by governments and others to reduce greenhouse gas emissions to the lowest possible levels in the shortest amount of time” – Alex Rogers, Scientific Director at the International Programme of the State of the Oceans
  • “There are few surprises in this report but the increase in the confidence around many observations just validates what we are seeing happening around us. Since the IPCC issued its last big report in 2007, terrestrial glacier loss and sea-level rise has dramatically accelerated; the Arctic summer sea ice losses are higher than originally projected and the last decade was the warmest since 1850.” – Samantha Smith, leader of WWF’s Global Climate & Energy Initiative
  • “It’s CO₂, mainly from burning fossil fuels, that dissolves in oceans and may destroy an already fragile ecosystem in an almost irreversible way if mankind does not shift from fossil fuels to renewables as soon as possible. Warmer and much more acid oceans are detrimental for fish, coral reefs and most other parts of marine ecosystems.” – Dr Stephan Singer, WWF’s director of global energy policy
  • “Scientific evidence confirms that manmade climate change is a reality and that without urgent action globally, the impacts will get worse. The time for debate is over, it is time to act. Rising temperatures will bring enormous economic and human cost. We need to support countries and communities most at risk in preparing to cope with disaster, to lessen the impacts of extreme weather events and help communities recover more rapidly when they do occur. The implications of melting ice caps and rising sea levels for people and economies around the world will be enormous, but it is the poorest and most vulnerable people who depend on the land and sea for their living who will be most affected. The report shows that there is time to put a halt to the continuing accumulation of carbon in our atmosphere, but that we need to move fast. As a developed, industrialised country the UK has to lead the way by ending our dependence on fossil fuels, and investing in clean, renewable sources of energy which we are fortunate enough to be blessed with in the UK. The science is clear, we have a moral duty to act and the risk of not doing so is too great. This is our opportunity to create the world we want to live in.” – Dr Alison Doig, Christian Aid’s Senior Climate Change Advisor
  • “The IPCC has confirms what many millions of people in the developing world are already well aware of, namely that the weather patterns have already changed for the worse. People in richer countries are vulnerable too, as floods, droughts and storms in Europe, North America and Australia have shown, but because of political inertia and powerful vested interests that have dominated media narratives for decades, they are less aware of the links between these impacts and their carbon emissions. Climate change affects us all and we must tackle it together. The time has come for global solidarity. This would enable the individual polluter (be they in a rich country or poor country) to recognise his or her personal responsibility and to try to connect with the victims of their pollution.  Climate change ignores borders, but so do friendship and solidarity. It is time for national interests to give way to the global good.  I hope the strong message from IPCC will galvanise actions by politicians and publics around the world.” – Dr Saleemul Huq, senior fellow in IIED’s climate change group
  • “The message of this report is clear – the Earth’s climate has warmed over the last century and man-made greenhouse gases have caused much of that global warming. The gases emitted now are accumulating in the atmosphere and so the solutions must be set in motion today. The risks and costs of doing nothing today are so great, only a deeply irresponsible government would be so negligent. Without urgent action to cut greenhouse gas emissions this warming will continue, with potentially dangerous impacts upon our societies and economy. This strengthens the case for international leaders to work for an ambitious, legally binding global agreement in 2015 to cut carbon emissions. This report is the most authoritative , credible analysis of climate change science ever. It represents a huge amount of work by over 250 unpaid scientific experts drawn from universities and research institutes in 39 different countries around the world. We owe them our gratitude because this report makes clear what is at stake if we don’t act.” – Ed Davey, UK Secretary of State for Energy and Climate Change
  • “Boil down the IPCC report and here’s what you find: Climate change is real, it’s happening now, human beings are the cause of this transformation, and only action by human beings can save the world from its worst impacts. This isn’t a run of the mill report to be dumped in a filing cabinet. This isn’t a political document produced by politicians. It’s science.” – US Secretary of State, John Kerry
  • “The report makes clear that the Earth is warming and the climate is changing, that human activities are primarily responsible, and that without very strong cuts in emissions of greenhouse gases, we face huge risks from global warming of more than 2°C by the end of this century compared with the period before the Industrial Revolution. All governments have already agreed that it would be dangerous to exceed a threshold of global warming by 2°C. Delay is dangerous because greenhouse gases are accumulating in the atmosphere and because we are locking in high carbon infrastructure and capital. This report points out that to have at least a 50 per cent chance of keeping within that limit, we must emit in total no more than about 820 and 1445 billion tonnes of carbon dioxide and other greenhouse gases during the rest of this century. Given that the world is currently emitting about 50 billion tonnes of greenhouse gases in terms of carbon-dioxide-equivalent each year, this report implies that, even if we were to stay at current levels, we would exhaust the emissions budget within 15 to 25 years. And if we continue to increase annual emissions, the budget will be depleted even sooner. That is why I think nations, cities, communities and companies will recognise the importance of these findings and will increase the urgency and scale of the emissions reductions that they are planning to undertake. I also expect this emissions budget to focus the minds of governments in the international negotiations towards a new climate change treaty, to be signed in Paris at the end of 2015. The transition to a low-carbon economy, led by private sector investment, in the context of sound public policy, will be full of opportunity, discovery, innovation and growth.” – British economist, Lord Nicholas Stern
  • “We’ve been missing the real public interest story in this over the years, the real public interest story isn’t is the science strong, the real public interest story is why is it as the science has got stronger and stronger, the politics have got weaker and weaker… Dealing with climate change – what we do about climate change – involves difficult political choices and political establishments across the spectrum have found it more comfortable to have a debate about the science than actually address those choices. It is not an economics problem, it is not a technology problem, it is a political problem in the end.” – John Ashton, former Special Representative for Climate Change at the UK Foreign and Commonwealth Office
  • “This is not just another report, this is the scientific consensus reached by hundreds of scientists after careful consideration of all the available evidence. The human influence on climate change is clear and dominant. The atmosphere and oceans are warming, the snow cover is shrinking, the Arctic sea ice is melting, sea level is rising, the oceans are acidifying, and some extreme events have increased. CO2 emissions from burning fossil fuels need to substantial decrease to limit climate change.” – Professor Corinne Le Quéré, Director of the Tyndall Centre for Climate Change Research
  • “What has changed significantly since the last report is that we have pumped an additional 200 billion tonnes of CO2 into the atmosphere. Annual emissions are now 60% higher than at the time of the first report in 1990 and atmospheric CO2 levels are the highest they have been for over 2 million years. So what are we doing in the UK to help reverse this reckless growth in emissions? Record levels of investment in North Sea oil, tax breaks for shale gas, investment in oil from tar sands and companies preparing to drill beneath the Arctic. Against this backdrop, the UK Treasury is pushing for over 30 new gas power stations, whilst the government supports further airport expansion and has dropped its 2030 decarbonisation target – all this alongside beleaguered plans for a few wind farms and weak energy efficiency measures.Governments, businesses and high-emitting individuals around the world now face a stark choice: to reduce emissions in line with the clear message of the IPCC report, or continue with their carbon-profligate behaviour at the expense of both climate-vulnerable communities and future generations.” – Professor Kevin Anderson, Tyndall Centre and the University of Manchester
  • “The latest IPCC report strengthens its earlier conclusions that most of the observed warming since 1950 has been caused by human activities, and future changes are inevitable.  Also, many of the other changes observed in the climate system, such as the rate of loss of Arctic sea Ice, melting of mountain glaciers and the Greenland Ice sheet are unprecedented.  Without immediate reductions in global emissions of greenhouse gases, the world will not be able to achieve the political target of limiting the increase in global mean surface temperatures to 2 degrees C, but rather we are likely to see an increase of 3-5 degrees C.  Time to act is running out if we are to take the threat of human-induced climate change seriously.” – Professor Bob Watson, Tyndall Centre for Climate Change Research and the University of East Anglia
  • “The Carbon Tracker Initiative welcomes the IPCC’s dialogue on carbon budgets. Their findings are consistent with our research, reiterating the need to identify unburnable carbon, wasted capital and stranded assets in the capital markets.” – Jeremy Leggett, Carbon Tracker chairman
  • “Today’s report shows the last 30 years were the warmest in 800 years. In that time our generation have grown up and scientists the world over have worked tirelessly to explain the problem. World leaders have barely lifted a finger. Our generation is organising a powerful global movement for change and we need world leaders to follow. The UK Youth Climate Coalition is calling for urgent national action on climate change, and for a fair and ambitious global deal in 2015 to go above and beyond the high-risk 2˚ carbon budget contained in today’s report. We can’t afford to lose another lifetime to inaction.” – Nick Sanderson, UKYCC
  • “The debate on man-made climate change is now over. Climate deniers live in the same parallel universe as people who think Elvis Presley is still alive and that the world is flat. It is crucial that the sections of the media that have spun junk science concede, and tell the truth today. The world’s top experts are sounding the global alarm and providing solutions on how to save our planet. Governments must listen to this wake up call and act urgently to stop the catastrophe.” – Luis Morago, Campaign Director for Avaaz

Top Tweets

  • MT ‏@EvolvingSun Stern: “Businesses need greater clarity from policymakers; need to understand #IPCC findings” http://on.ft.com/1fWiWrl
  • MT ‏@diana_cm86 15 things you should know about the new #IPCC report http://thkpr.gs/1fNfzmA via @climateprogress #climatechange
  • MT @CongressEA #Business reactions to the #IPCC report. Risks are known already but action needs to be stepped up http://bit.ly/16wDp4O
  • RT @GreenIsTweet #Climate Report: Everything you wanted to know http://bit.ly/16CX0Aj  #environment #warming #IPCC
  • RT ‏@tom_burke_47 Manmade global #warming is leading to catastrophic & irreversible consequences http://bit.ly/16CYgU6 #IPCC #climate
  • RT @Progressio #IPCC confirms #climate change is real & urgent. The evidence is ‘unequivocal’, the #debateisover & it’s time for actio
  • ‏RT @IanJSinclair The story #IPCC tells “is of climate breakdown” – George Monbiot http://bit.ly/14Pv2hr