Special Alert: IPCC Synthesis Report


The final instalment of the Fifth Assessment Report (AR5) by the Intergovernmental Panel on Climate Change (IPCC) is due for launch on 2 November in Copenhagen, Denmark – after  a week of government negotiations to agree a Summary for Policymakers (SPM). Following the reports of three Working Groups over the past year – covering the physical science of climate change (Working Group 1), vulnerability to climate impacts and adaptation (Working Group 2), and mitigation strategies to tackle climate change (Working Group 3) – the final element of the AR5 series will be a “Synthesis Report”, combining and contrasting the work of the three Working Groups into one report. It marks the culmination of a 5-year-effort by 830 authors, 1200 other contributors and 3700 expert reviewers drawing on more than 30,000 pieces of research and 143,000 expert comments to produce an unprecedented body of evidence.

Looking at the reports launched so far as part of the AR5 process, the IPCC has unequivocally shown that climate change is here, man-made and already having dangerous impacts across all continents and the ocean. The most exhaustive and authoritative climate study to date, the AR5 report also make it clear that global warming can still be kept below the politically agreed limit of 2DegC compared to preindustrial levels, and that securing a safe climate future does not have to cost the earth. Launched by UN Secretary General Ban Ki-moon on 2 November, the Synthesis Report will build on these crucial findings. It is expected to say that we can go down a clean energy path where we enjoy economic benefits and manage to adapt to modest climate change, or follow a path with increasing carbon pollution worldwide where severe climate change threatens our societies and derails our economies.

In real world terms, this means the AR5 report will present governments – that have ordered and endorsed this blockbuster report – with a choice: invest in clean energy going forward, or continue to invest in fossil fuel infrastructure. The IPCC scientists are sending this important message at a critical time for the UN climate negotiations, as governments have committed to negotiating a new global agreement by 2015. Following the recent Climate Leaders Summit in New York and the largest public mobilisations ever in favour of climate action, the final and complete AR5 report is the last word from the scientific community ahead of the all-important COP21 meeting in Paris next year – telling world leaders who are busy re-engaging in the climate debate what they need to know if they want to speed up the ongoing transition from dirty to clean energy that a growing chorus of voices from all sectors and geographies demand.


MT @ClimateReality: #IPCC: Warming increases risk of severe, pervasive & irreversible impacts for people & ecosystems http://bit.ly/1zkVuA


Key Points

  • A month after hundreds of thousands of people took the the streets in an unprecedented call for climate action, the world’s leading scientific body will confirm that climate change is real, caused by humans and requires urgent and deep cuts in emissions. In a record-breaking mobilisation, 700,000 people took to the streets across the world last month to call for strong and urgent climate action. Now the latest report from the IPCC – prepared by hundreds of the world’s leading climate experts – will offer the most comprehensive, authoritative and scrutinised assessment of climate science ever produced.
  • The world is unprepared for the growing economic and social costs of climate change and the many other grave consequences for communities and the environments on which they depend. With air temperature and sea levels rising, precipitation patterns changing, sea ice declining and oceans acidifying, the IPCC shows that we are already experiencing severe climate impacts on every continent and across the seas. Vulnerable countries and communities are likely to be the hardest hit, as climate change threatens so many of life’s basics: water, food, shelter, and safety.
  • The risk posed by climate change can be reduced, but only if governments aim for a complete phase out of fossil fuel pollution. Scientists say we can still keep global warming below the internationally agreed threshold of 2DegC, but governments can only honour that commitment if they stick to a tight carbon budget and transition away from dirty fossil fuels and to 100% renewable energy. This will mean divesting at least $30 billion per year from fossil fuels in coming decades and increasing annual investment in low carbon electricity to US $147 annually. Those continuing to invest in high-carbon infrastructure are at risk of their assets losing value and becoming “stranded”.
  • Climate action will cost virtually nothing, while bringing about a host of advantages. Under business-as-usual scenarios, consumption grows by 1.6 to 3% per year. Ambitious climate action would reduce this growth by just 0.06% and that’s before taking into account the multiple benefits of avoiding future climate impacts. The IPCC makes it clear that preventing catastrophic climate impacts comes at a lower cost than breaking through the 2DegC danger threshold, and the longer we delay the low-carbon transition, the more expensive addressing climate change will be.
  • Renewable energy can power our society, drive the economy and give us cleaner air. Moving from fossil fuel based energy to renewables will result in a wide range of benefits – including jobs and improved public health. The clean energy transition is inevitable, people are demanding it, and it is already underway. It is now up to governments to put in place the enabling policies to speed up this transition. Addressing the climate challenge will also help government leaders in another challenge for 2015; agreeing a to-do list for ending poverty worldwide – an impossible task without tackling climate change.
  • Government leaders have put climate change back at the top of the political agenda and early next year they must put forward their climate action commitment for the Paris 2015 climate deal. The IPCC presents governments with a clear choice; go down a clean energy path or continue down a path built on carbon pollution and littered with severe climate impacts. At the New York Climate Summit, world leaders acknowledged they could no longer ignore the will of people and businesses for accelerated climate action, and 2015 offers them a critical opportunity to show that the fossil fuel age is over, and a new era of renewable energy has begun.


The reports of the Intergovernmental Panel on Climate Change (IPCC) serve in many respects to underpin the international community’s understanding of climate change. The IPCC does not conduct its own research. Instead scientists from universities, think tanks, businesses and non-profit groups around the world assess and synthesise the most recent climate change-related science, making the reports the most authoritative scientific assessments worldwide.

The latest IPCC assessment report – AR5 – has been launched in four separate instalments over the course of 2013 and 2014. Over the three Working Groups the IPCC has laid out the physical science of climate change; its impacts, vulnerability and adaptation; and mitigation options across all countries and sectors. The final instalment will be the Synthesis Report, bringing together the work of the three Working Groups into one report.

Looking at the three Working Group reports together, they confirm what scientists have been saying for some time: there is now extreme certainty that climate change is happening and that humans have caused the majority of it. As global carbon emissions reach record levels and keep rising, the IPCC confirms that climate change is already impacting all continents and the oceans, resulting in changes that are often unprecedented and could be irreversible.

The world has currently seen 0.85DegC of warming on 1880 levels and significant impacts are already affecting communities worldwide. The atmosphere and oceans have warmed, sea levels have risen, and the amounts of snow and ice have diminished. If the world stays on its current path, the picture only becomes more grim. The AR5 report shows that the scientific understanding of future risks has been strengthened in recent years, and that escalating temperatures are expected to derail our economies, erode food security and exacerbate social and economic inequalities.

According to the IPCC, using scenarios which roughly equate to continuing business-as-usual, global temperature rise will reach around 4DegC above pre-industrial times, with catastrophic impacts for people and planet. But the report does not rule out the possibility of holding global warming to below 2DegC – the limit agreed upon by the world’s governments – or even 1.5DegC, a lower threshold that the world’s most vulnerable nations are pushing for.

For the first time the IPCC has outlined a carbon budget, which shows that for a two-thirds chance of keeping global warming below the 2DegC threshold, the world needs to cap total emissions, since 1870, at 2900 gigatonnes. As of 2011, two-thirds of this budget had already been spent. That means to keep temperature rise below these levels by the year 2100, significant emission reductions are needed in the next two decades (even more to limit warming to 1.5DegC).

It won’t be easy, but such action is possible. The IPCC is clear; to stay below 2DegC of warming will require leaving the majority of the world’s fossil fuel reserves in the ground, phasing out the use of oil, coal and gas use completely, with a global CO2 emissions peak and a decline towards zero in the long term.

To replace fossil fuels, the IPCC says we will need to triple our use of zero and low carbon energy by 2025. With renewable energy having improved dramatically in performance and cost-efficiency in recent years, the AR5 report paints existing technologies such as wind and solar as increasingly attractive options, with even stronger future prospects. This is particularly the case if governments put in place stronger enabling policies, for example encouraging a switch in investments from dirty to clean energy, the elimination of perverse subsidies, and incentives to use less energy overall in buildings, transport and industry, which in turn can save money.

And securing a safe climate future will not cost the earth, according to the IPCC. In business-as-usual scenarios, consumption grows by 1.6 to 3% per year. Ambitious mitigation would reduce this growth by only around 0.06% a year, i.e. 2.94% growth instead of 3% growth. And this is before we consider the co-benefits of taking action – such as better public health and increased energy efficiency – or the cost savings which result from avoiding future impacts. Looking at the low costs, the co-benefits and the savings, it’s clear that climate mitigation is an economic no-brainer.

The fifth assessment report has the potential to significantly enhance public awareness about climate change. Each report contains a Summary for Policymakers (SPM) which is intended to aid policymakers and is negotiated line by line by governments. The final product will also be endorsed unanimously by the world’s governments. This government ownership of the IPCC report should further encourage policymakers to take the actions necessary to mitigate and adapt to the very climate change their own reports detail.




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Key Quotes

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, Working Group I Co-Chair
  • “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
  • “The IPCC has confirmed 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.” – Dr Saleemul Huq, senior fellow in IIED’s climate change group
  • “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 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

Working Group II

  • “We live in an era of man-made climate change. In many cases, we are not prepared for the climate-related risks that we already face. Investments in better preparation can pay dividends both for the present and for the future.” – Vicente Barros, Working Group II Co-Chair
  • “Scientists are warning us, but they are not telling us to give up. The solutions are already here. A growing wave of people, communities, corporations and investors around the world are already making a difference by moving to clean and safe renewable energy and demanding governments to stand with them. There’s a better future than the one we are currently offered and it’s ours if we want to grasp it.” – Greenpeace International Senior Political Advisor Kaisa Kosonen
  • “Climate change is hugely threatening to our way of life, in the UK, Europe and the world. Not to lead is deeply irresponsible. If you don’t lead, you will not bring others with you.” – UK Energy and climate change secretary Ed Davey
  • “The report talks about the economic cost of climate change. But the true cost of climate change cannot be represented just in monetary terms. There can be no cost put to losing a husband, a mother, a son or a daughter; there can be no cost to losing the home where our ancestors settled hundreds of years ago; there can be no cost to losing an ecosystem that sustains our life and the life of the earth we call home. This is the true cost of inaction on climate change.” – Senior Adaptation Policy Advisor from WWF International, Sandeep Chamling Rai

Working Group III

  • “Climate policies in line with the two degrees C goal need to aim for substantial emissions reductions. There is a clear message from science: to avoid dangerous interference with the climate system, we need to move away from business as usual. Many different pathways lead to the future within the boundaries set by the two degrees C goal. All of these require substantial investments. Avoiding further delays in mitigation and making use of a broad variety of technologies can limit the associated costs.” – Ottmar Edenhofer, Working Group III Co-Chair
  • “The longer we delay on tackling climate change, the harder the challenge becomes. We know more effort is needed, and quickly. Delaying new mitigation efforts will make it much harder to transition the world’s energy systems to a sustainable, equitable and low-emissions future. Transforming the world’s energy systems is now an urgent necessity if we are to avoid the dangerous impacts of global warming.” – Samantha Smith, leader of the WWF’s Global Climate & Energy Initiative
  • “The Climate Group has been working with business and government partners to drive a ‘clean revolution’. The IPCC reports make it clear this needs to happen now… 70-80% of the necessary technology is available today. What is needed is a combination of coordinated policy and corporate leadership to accelerate the transition” – Mark Kenber, CEO, The Climate Group
  • “The IPCC’s findings confirm that climate change is a man-made phenomenon that has emerged from largely unequal human development patterns. Even though a small, rich segment of the global population has caused the vast majority of greenhouse gas emissions, it is the world’s poorest people who are increasingly suffering from growing climate disruption. This is an extreme global injustice.” – Sven Harmeling, Climate Change Advocacy Coordinator, CARE International

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