People’s Climate March in New York 21 September. Photo: maisa_nyc/flickr.com/ CC BY-NC-SA
Two-thirds of the carbon budget needed to keep global temperature rise below 2°C has already been spent. To replace fossil fuels we will need to triple our use of zero- and low-carbon energy by 2025.
In the most comprehensive, authoritative and scrutinised assessment of climate change ever produced, the Intergovernmental Panel on Climate Change (IPCC) has offered its starkest warning yet about the challenges facing humanity. Not only does the IPCC show that climate change is real and that its impacts are happening faster than ever, but for the first time it lays out the true extent of human influence on the climate system. While previous estimates say human activity – primarily the burning of fossil fuels – is responsible for more than half of all warming, the latest report shows we are actually responsible for all warming since 1951.
But the main takeaway for decision makers is this: governments can no longer just talk about emissions reductions, they need to work towards a complete phase-out of fossil fuel emissions globally. The IPCC makes it clear that emissions need to fall to zero if the world is to keep global warming below the internationally agreed limit of 2°C. In the words of experts and observers tracking the IPCC process: “The science is in and it’s game over for fossil fuels.” For the first time, the Fifth Assessment Report includes a strict carbon budget for governments, of which over two-thirds have already been used up. At current rates the world would burn through the rest in less than 30 years. For the best chance of avoiding severe levels of warming, governments will need to peak emissions, rapidly phase fossil fuels down to zero and transition to 100 per cent renewable energy.
Such a transition is not only possible, but is economically viable, according to the IPCC. Rapid development of renewables since the body’s last Assessment Report in 2007 means that clean energy is cheaper and stronger than ever before, and bringing multiple societal benefits – including increased energy access, jobs and improved public health. Continuing down such a path and investing in renewable energy in the next few decades will also be cheaper than paying a rapidly growing bill for “severe, pervasive, and irreversible impacts”. Such cost savings would vastly outweigh the costs associated with the clean energy transition, says the IPCC.
Requested and endorsed by governments, the release of this report – which ends a five-year process covering 30,000 pieces of evidence and involving over 2000 scientists – should act as a guide for governments working on a new global climate agreement, which is due for sign-off in Paris next December. Speaking at the launch press conference, IPCC Chair Rajendra Pachauri said the scientists were now “passing the baton to policymakers and the decision-making community” to act on the report’s findings. UN Secretary-General Ban Ki-moon warned that “the science has spoken, there is no ambiguity in the message. Leaders must act now, time is not on our side.”
Looking at the IPCC AR5 report in its entirety, it confirms and underlines what many scientists have been saying for some time: there is now extreme certainty – more than ever before in the history of climate science – that climate change is happening and that humans have caused the majority of it. In fact, the report makes it clear that all warming since 1951 is due to human activity. As global carbon emissions have reached record levels and keep rising, the AR5 report also confirms that climate change is already impacting all continents and the oceans, resulting in changes that are often unprecedented and could partly be – or soon become – irreversible.
With current warming of 0.85°C compared to 1880 levels, significant impacts of climate change are 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 grimmer. The AR5 report shows that the scientific understanding of future risks has been strengthened in recent years, and that escalating temperatures are expected to slow economic growth, 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 a range of 4°C above pre-industrial times, which would be catastrophic for people and the planet. The governments of the world have previously agreed on the need to limit global temperature rise to less than 2°C above pre-industrial times, with many of the most vulnerable nations on Earth calling for a cap at 1.5°C. The AR5 report doesn’t rule out the possibility to achieve this, but paints a picture of massive changes in how we power our economies in order to get there.
To this end, the IPCC has – for the first time – outlined a carbon budget. This budget states that for a two-thirds chance of keeping warming below the 2°C threshold, the world will need to cap total emissions, since 1870, at 2900 gigatonnes. However, as of 2011, two-thirds of this budget had already been spent. Therefore, in order to keep global temperature rise below 2°C by the year 2100, significant emission reduction efforts will be required over the coming two decades (and accordingly, even more significant and even faster measures to stay below 1.5°C).
Efforts of this magnitude are possible, but will require large-scale changes in our current energy system – given that two-thirds of man-made emissions result from burning fossil fuels. The IPCC is quite clear that we will stand no chance of preventing catastrophic warming if we do not leave the majority of the world’s fossil fuel reserves where they are now: in the ground. Furthermore, the report shows that if we want to keep emissions at a safer, stable low level we have to completely phase out unabated oil, coal and gas use, with global (net) CO2 emissions peaking and then declining toward 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.
In fact, the IPCC lays out a stark choice for us: we can go down the clean energy path on which economic growth is strong, or we can take the carbon pollution path on which economic growth is derailed by climate change. In business-as-usual scenarios, consumption grows by 1.6 to 3 per cent per year, not including the need to pay for the cost of worsening impacts. Ambitious mitigation would reduce this growth by only around 0.06 percentage points a year, i.e. 2.94 per cent growth instead of 3 per cent growth. The IPCC’s economic assessments of the cost of mitigation don’t even include 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.
No surprise then that the IPCC also warns that delaying mitigation action now is a bad idea and implies higher costs of acting later. But even if we don’t wait, the costs of action can still differ significantly, depending on which energy options we choose. In the context of zero- and low-carbon energy sources, for example, the report also references nuclear energy and carbon capture and storage (CCS), in addition to renewables. It points out, however, that nuclear is expensive and holds many risks, and that CCS is more theory than practice and has not been proven at scale – major roadblocks not faced by the booming and mature renewables industry.
The controversial topics of geoengineering and carbon removal are also discussed in the report, but with multiple caveats – including the fact that they carry with them severe risks, come at a very high cost, and have not been proven at scale. The IPCC’s approach to such technologies reflects the fact that they are widely seen as a distraction when cheaper, safer and cleaner solutions such as renewable energies are available but haven’t been fully tapped yet. One particular technology receiving some attention in the report is Bioenergy with Carbon Capture and Storage (BECCS). BECCS is an essential part of some low-emission scenarios in the AR5 report, but it comes with drawbacks including high costs and the need to use arable land and water resources to produce biofuels.
In New York, in September, government leaders put climate change back on the political agenda. Now the IPCC report provides them with a roadmap to a new global climate agreement, which is due next December in Paris. A few months after hundreds of thousands of people took to the streets in New York and elsewhere around the world in an unprecedented call for government action to tackle climate change, government leaders know they can no longer ignore the will of the people and businesses for accelerated climate action and need to deliver if they don’t want to end up on the wrong side of history.
Laying the foundations for success in Paris, governments are expected to pen a draft agreement this December at the UN climate talks in Lima, and follow up with national climate action plans by March. Those national commitments and the climate agreement in Paris will signal a collective decision by governments to get serious about speeding up the just transition of the global economy that is already underway.
The IPCC presents governments – which ordered and endorsed this report – with a clear choice: invest in clean energy or spend the future dealing with climate disaster after climate disaster. The people have spoken, businesses are demanding action, investors want long-term certainty, and the science is clearer than ever. 2015 provides governments with a critical opportunity to show that the fossil fuel age is over, and a new era of renewable energy has begun.
Ria Voorhaar, Climate Action Network International
Christian Teriete, Global Call for Climate Action