By Renate Christ, Secretary, Intergovernmental Panel on Climate Change.
In November 2014, the Intergovernmental Panel on Climate Change (IPCC) released the final instalment of the Fifth Assessment Report (AR5).This is a key input into the climate negotiations being conducted under the UN Framework Convention on Climate Change (UNFCCC) that are intended to result in a global, legally binding agreement to tackle climate change. The next full round of negotiations, or Conference of the Parties, takes place in Paris in December and is known as COP21.
Comprising contributions from each of the IPCC’s three working groups, plus a Synthesis Report, AR5 is the most comprehensive and largest assessment of climate change – its causes, its impacts, possible future risks and options for adaptation and mitigation – produced to date. I would like to look at some of the key findings of that report, but also examine how the IPCC, in what has been described as one of the largest scientific endeavours ever undertaken, reached those conclusions.
The different components of AR5 can be found on the IPCC website (www.ipcc.ch). A very brief summary of the contents – four volumes of over 4,800 pages – can be found in the 21 headline statements of the Synthesis Report, which distils and integrates the findings of the working group contributions.1 In presentations to different audiences we often highlight three conclusions:
- human influence on the climate system is clear;
- the more we disrupt our climate, the more we risk severe, pervasive and irreversible impacts;
- we have the means to limit climate change and build a more prosperous, sustainable future.
It’s worth considering how the report’s 830 authors, supported by hundreds of other scientists and experts, reached these and other conclusions. Like all science, AR5 builds on previous work. For example, the conclusion in the contribution of Working Group I (the physical science basis of climate change) is that “it is extremely likely that human influence has been the dominant cause of the observed warming since the mid 20th century”.
This is an advance on the finding of the Fourth Assessment Report published in 2007 that “most of the observed increase in global average temperatures since the mid 20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations”.
That 2007 finding in turn built on the Third Assessment Report in 2001, which noted that “most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations”. In IPCC usage, ‘extremely likely’ means with at least 95 per cent certainty, ‘very likely’ with at least 90 per cent certainty, and ‘likely’ at least 66 per cent.
So, what enabled the AR5 authors to express this greater certainty? They drew on multiple lines of evidence – higher atmospheric and oceanic temperatures, diminishing amounts of snow and ice, rising sea levels and increased concentrations of greenhouse gases – to conclude that warming of the climate system is unequivocal, and that many of the observed changes since the 1950s are unprecedented.
This strong statement was made at a time when some bloggers were arguing that the slowdown in the rate of surface temperature increase over the previous 17 years showed that global warming had stopped.
The scientific community continues to examine the reasons for the slowdown in surface temperature rise in recent years. Global mean surface temperature exhibits substantial variability from one year or decade to the next, and trends based on short records are very sensitive to the beginning and end dates.
For example, if the start year is a hot one the trend will be lower than by starting with a relatively cool year. Longer-term observations, however, show a clear trend. Each of the past three decades has been successively warmer than the preceding decades since 1850. An important finding of the Working Group I report in this context is that in the 40-year period from 1971 to 2010, more than 90 per cent of the net energy increase in the climate system was stored in the ocean.
Having established the fact of warming, the IPCC scientists then looked at the causes. An analysis of the contributions to observed surface temperature change shows that the warming effect of greenhouse gas emissions, less the cooling effect of other human caused drivers such as aerosols, corresponds closely with the observed warming, while natural factors, such as changes in solar irradiance and emissions from volcanoes, are negligible. This is what enabled the IPCC scientists to conclude that it was extremely likely that human influence was the dominant cause of the observed warming.
I have taken some time to discuss this conclusion, but there are plenty of other examples in AR5 where the findings of the IPCC rebut arguments that play down the threats of climate change. The Working Group II contribution (impacts, adaptation and vulnerability) makes it clear that the impacts of climate change are already being felt on every continent, from the poles to the equator, from the mountains to the seas, and in both rich and poor countries.
At this point it is worth recalling that the IPCC does not conduct its own research or its own measurements of climate data. The mandate of the IPCC is to assess the thousands of scientific publications produced each year that are relevant to climate change. The IPCC establishes what is known and not known about climate change. Where necessary it highlights disagreements and controversies in the scientific community. But the IPCC does not have its own view. It simply reflects the overall understanding of the scientific community on this subject.
The objectivity of the IPCC goes beyond this. While it may lay out options for governments to tackle the risks of climate change, it never tells them what to do. The IPCC is policy-relevant but never policy-prescriptive. The authors of Working Group III (mitigation of climate change) like to use the image of a mapmaker: the scientists produce a map for policymakers that will enable them to reach their goals. They show multiple mitigation pathways that limit warming, along with technological, economic, social and institutional challenges and explain implications of timing of mitigation efforts, but it is the policymakers that decide which route to follow. This neutrality is one of the pillars of the IPCC.
But what makes an IPCC report so robust is the unique partnership between scientists and policymakers. The IPCC’s members are the world’s governments, and it is they who request the scientific community produce a report. After repeated drafting by the IPCC’s authors, helped by review comments from governments and other experts in the scientific community, the governments then examine the Summary for Policymakers of each instalment of the report in detail.
In an approval session, the government representatives propose changes for the sake of clarity and consistency. The scientists responsible for that part of the report decide whether the proposed change is scientifically sound and consistent with the underlying report. Only then will it be accepted. The result of this dialogue between those who request the report and will use it, and those who write it for them, is a strong text endorsed by both policymakers and the scientific community. At the end of the session the Summary for Policymakers is approved by consensus, and by extension the full report is accepted, meaning that the world’s governments stand behind the findings.
The work of the IPCC does not stop there. Besides an extensive programme of outreach to present the findings to stakeholders in different countries, IPCC authors also take part in regular dialogues with negotiators at the UNFCCC negotiating sessions. Detailed presentations are followed by in-depth discussions to ensure that negotiators have a thorough understanding of the report’s conclusions.
As a result, the last full session of the UNFCCC, COP20 in Lima, explicitly welcomed AR5, acknowledged it provided the scientific foundation for the negotiations, urged negotiators to use the information in AR5 in their discussions, and invited the IPCC to continue to provide information to its parties.
1www.ipcc.ch/news_and_events/docs/ar5/ar5_syr_headlines_en.pdf
Photo: IPCC Approval and Acceptance of Working Group III Assessment Report 5, Berlin, 2014
From: Climate 2020
A Iniciativa Verde, por meio do projeto Adaptação às Mudanças Climáticas no Litoral Sul de São Paulo em parceria com o Instituto HSBC Solidariedade, traduz pela primeira vez em português o “Sumário para tomadores de decisão do 5º Relatório de Avaliação do IPCC, Grupo de Trabalho II – Impactos, Avaliação e Vulnerabilidade” (são 46 páginas) do 5º Relatório de Avaliação do Clima do Painel Intergovernamental de Mudanças Climáticas (IPCC). A versão foi autorizada pela Organização das Nações Unidas (ONU), responsável pelo IPCC. O documento está disponível online por meio da seção Nossas Publicações, no site da Iniciativa Verde.
O sumário foi entregue em abril para o Comitê da Bacia Hidrográfica do Ribeira de Iguape e Litoral Sul, no estado de São Paulo, local onde o projeto foi desenvolvido. “Ele é fundamental para a criação de políticas públicas que visem a adaptação de nossos ecossistemas e populações para os impactos das mudanças climáticas globais”, diz Lucas Pereira, diretor técnico da Iniciativa Verde.O objetivo é que o documento seja usado como base para a aplicação de ações de adaptação às mudanças climáticas e para que todos os interessados, mesmo aqueles que não participaram do projeto, tenham acesso ao documento. Além disso, o relatório traduzido é um dos produtos resultado do projeto executado pela Iniciativa Verde.
O relatório lançado em inglês em 2014, o mais recente do IPCC, apontou que o aquecimento global é uma realidade e a contribuição do ser humano é significativa para a ocorrência de fenômenos ligados às mudanças climáticas. Por isso, devemos agir imediatamente em escala global para reverter o que for possível. Leia um resumo do documento feito pelo biólogo Magno Castelo Branco, doutor em Ecologia e Recursos Naturais.
Para saber mais sobre o Projeto Mudanças Climáticas e o Futuro das Comunidades do Litoral Sul Paulista, acesse: http://www.iniciativaverde.org.br/programas-e-projetos-hsbc-solidariedade.php .
Fonte: Iniciativa Verde
At the UN climate change conference in Bonn, governments are looking at ways to increase ambition to tackle climate change before 2020, when the new Paris 2015 climate agreement is to enter into effect. One key focus of a Technical Expert Meeting 5 and 6 June will be opportunities to accelerate energy efficiency action in urban environments.
Cities account for 70 per cent of global energy use and for 40 to 50 per cent of greenhouse gas emissions worldwide. Urban areas are projected to grow rapidly over the coming years, so reducing the amount of energy consumed in cities is central to the fight against climate change. The sectors with the greatest potential to save energy are buildings, district energy, transport and lighting.
The reasons to make more efficient use of energy apart from fighting climate change are compelling. Millions of new jobs can be created when enough companies are involved in energy conservation. And saving energy has obvious cost benefits, so that the International Energy Agency (IEA) calls energy efficiency “the world’s first fuel”.
At the UN Secretary General’s Climate Summit last year, countries, cities and corporations launched large-scale commitment to double the rate of global energy efficiency by 2030 through vehicle fuel efficiency, lighting, appliances, buildings and district energy.
Developed countries need to take the lead on energy efficiency. Yet efficient energy use is equally critical in developing countries where affordable and reliable energy is already in short supply and energy providers already struggle to meet the demands of growing economies.
Examples International Cooperation in the Lighting and Transport Sectors
There are many inspiring examples of how international cooperation can boost energy efficiency measures, also under the UNFCCC. For example, Indonesia’s current energy production - primarily from coal - is rising alongside its recent economic growth.
To increase energy efficiency, the country has proposed a Nationally Appropriate Mitigation Action (NAMA) dubbed the Street Smart Lighting Initiative (SSLI) that aims to increase the efficiency of lighting by substituting conventional street lighting with more efficient technologies in cities and urban areas. UNFCCC chief Christiana Figueres visited a similar project in the Philippines earlier this year.
International cooperation is also key to reducing energy consumption in the transport sector. Low-carbon transport systems such as rapid bus systems can reduce pollution above all in urban areas. For example, transportation accounts for approximately half of the energy consumption and 31% of global CO2 emissions in Mexico. As part of a bilateral collaboration between the governments of Mexico and Germany, a new nationally appropriate mitigation action (NAMA) was recently submitted to the UNFCCC’s NAMA registry to enable “Eco-driving” courses for truck drivers. Other great examples are NAMAs that support energy efficient transport initiatives in Colombia and Ethiopia.
According to the IEA, buildings alone are the largest energy consuming sector in the world, and account for over one-third of total final energy consumption and an equally important source of carbon dioxide emissions.
Over the next two decades an area roughly equal to 60 percent of the world’s total building stock is projected to be built and rebuilt in urban areas, most of them in developing countries. Widespread implementation of best practices and technologies could see energy use in buildings stabilize or even fall by 2050.
In light of this, the International Union of Architects (UIA) has made a significant move by pledging to phase out carbon emissions by buildings by the middle of the century.
Insulating old buildings is another obvious way to reduce energy consumption. A briefing by the European Climate Foundation, Local Governments for Sustainability (ICLEI) and the University of Cambridge found that good insulation can reduce heating bills by as much as 90%, at the cost of as little as 100 US dollars per square metre.
Intelligent heating and cooling systems which apply to entire cities are also crucial for urban energy efficiency. A recent report by the UN Environmental Programme shows that transition to modern district energy systems could contribute to 60 per cent of required energy sector emissions reductions by 2050, and reduce primary energy consumption by up to 50 per cent.
There are many examples of how district energy systems can help save energy and money. The city of St Paul, Minnesota, USA, uses district energy fuelled by municipal wood waste to displace 275,000 tons of coal annually and to keep US$12 million in energy expenses circulating in the local economy.
Another good example is Paris, the host city of the UN climate change conference in December. Paris has developed Europe’s first and largest district cooling network, part of which uses the Seine River for cooling.
One Can Only Manage what One Can Measure
At the end of the day, one can only manage what one can measure. Energy efficiency efforts of cities are captured by organizations such as ICLEI Local Governments for Sustainability andC40 Network of major cities, which both demonstrate that both the scope and pace of local climate action is accelerating.
A top source of information of efforts of cities to be energy efficient is the UN’s newly updated NAZCA Portal, designed to catalyze public and private sector action on climate change before and after 2020, when the Paris universal climate agreement will take effect.
A blistering heat wave in India has killed nearly 1,400 people in the country in less than one week.
At least 1,020 people have died in Andhra Pradesh in southeastern India, while 340 people have died in the adjacent state of Telangana. In northeastern West Bengal and Orissa, at least 24 people have died. Most of the deaths, according to officials, have been among construction workers, the elderly, and the homeless — people who are typically most exposed to high heat and who don’t have access to air conditioning.
“Almost all the victims are old,” said B.R. Meena, principle secretary for revenue for Telangana. “Inquiries reveal that most of them were working and were exposed to the heat. Dehydration and heat stroke caused the deaths.”
In some regions, temperatures have reached a scorching 122°F — heat that’s melted sections of roads in some cities and that’s close, according to the Guardian, to the country’s all-time high of 123°F. Parts of the country had slightly lower temperatures, but the heat was exacerbated by high humidity: in Lucknow, the capital city of Uttar Pradesh, temperatures reached 110.3°F, with relative humidity of 70 percent. Delhi announced Monday that it had reached its hottest temperature of the season of 113°F.
Officials in Andhra Pradesh have taken steps to try to minimize the impact of the heat wave.
“The state government has taken up education programmes through television and other media to tell people not to venture into the outside without a cap, to drink water and other measures,” P. Tulsi Rani, special commissioner for disaster management in Andhra Pradesh, said. “We have also requested NGOs and government organisations to open up drinking water camps so that water will be readily available for all the people in the towns.”
India’s government has promised to provide monetary compensation to families of the dead, and officials have warned Indians in the hardest-hit regions to stay indoors and drink lots of water. Staying indoors won’t provide much relief to the third of India’s population who don’t have electricity, however.
But those in India who do have power are putting strain on the nation’s electrical grid with their high use of air conditioning and fans. In Delhi, high temperatures — and subsequent high usage of air conditioning — have led to fears of power cuts in the city and in other regions where mercury has soared. Power cuts are a common fear in India, where aging infrastructure is struggling to keep up with a populace that’s increasingly installing air conditioners and other electric machines. Indians have dealt with major power outages before: in July 2012, one of the worst blackouts in recent years left 700 million people without power. Solar power, however,could help improve the country’s grid reliability.
Meteorologists are predicting that India will endure a few more days of extreme heat before getting some relief. Even after temperatures drop later this week, they’ll likely spike again, though in the next few weeks, the country should see some sustained relief from the monsoon rains.
India is no stranger to heat waves. In 2010, the country also endured a major wave of high temperatures that killed hundreds of people. In 2013, too, intense heat claimed the lives of more than 500 people in the country. And climate change — which is contributing to extreme heat around the world — has already contributed to an increase in heat waves between 1961 and 2010.