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The Paris Agreement and the Wicked Problem of the Carbon Budget

The Paris Agreement agreed in December 2015 changed the environmental landscape and provided a clear framework for dealing with climate change. It lays down the principle that global temperatures should not exceed 2oC and that efforts should be pursued to limit the global temperature increase 1.5oC above pre-industrial levels, “recognizing that this would significantly reduce the risks and impacts of climate change.” Christiana Figueres, (the former UNFCCC Executive Secretary), said in January 2016 that, “We don’t have an option, we have to address climate and in fact we have to address it at a faster rate than our own wonderful and well beloved Paris Agreement says, because we have to reach peaking very very quickly, in order to protect the most vulnerable and in order to protect developing countries.”

However, in the period since the Paris Agreement was negotiated there have been a number of scientific articles which question whether even the 2oC target is achievable, the latest being the article, “Less than 2oC warming by 2100 unlikely”, by Raftery et al published in Nature Climate Change in July 2017, which estimates that there is only a 5% chance of meeting the 2oC target by 2100, and a 1% chance of meeting the 1.5oC target. This is no doubt that any increase in average global temperatures will have a serious impact, and Knutti et al say that at 4˚C, and above, changes to the physical climate system increase and may be non-linear.

A paper called “2020 The Climate Turning Point”, published by the NewClimate Institute for Climate Policy and Global Sustainability, with a preface by Rahmstorf and Levermann of the Potsdam Institute for Climate Research, takes the view that the Paris Agreement targets have to be met and that global emissions must peak by 2020. Rahmstorf and Levermann do, however, acknowledge the difficulties and say, “We will need an enormous amount of action and scaled up ambition to harness the current momentum in order to travel down the decarbonization curve at the necessary pace; the window to do that is still open.”

Rahmstorf and Levermann are highly respected scientists working at the Potsdam Institute for Climate Impact Research, both have many published papers to their credit, wrote the preface to this Report, which reflects the scientific consensus.  The body of the Report was written by Chloe Revill and Victoria Harris, who are described as “Independent Policy Analyst and Writer.” I think that this Report should really be called a policy initiative, or an attempt to influence policy-makers. The Report, does however ultimately fail to give a clear pathway to achieving a zero-carbon economy by the middle of the 21st century, which will be necessary in order to achieve the targets set by the Paris Agreement. The preface is correct, in its assertions, in particular when it states the importance of remaining well below 2˚C of global warming, and as close to 1.5˚C as possible. It is undoubtedly clear that the present level of global warming, which according to the World Metrological Organization had already reached 1.2˚C by 2016, is causing serious damage. It has, for example, locked in significant sea level rises over the next few thousand years, and any increase in emissions will only increase the dangers. Rahmstorf and Levermann also cite a carbon budget for the remainder of the 21st century in the range 150 to 1,050 Gt C02 to reach the Paris Agreement temperature targets. This is in line with other authorities, for example Friedlingstein et al give a budget of 1,130 Gt C02 (2017-2100) with a 66% probability of achieving the 2˚C target.

I conclude that something more is actually needed in order to live within the carbon budget, over and above the measures proposed in the Report; this may include new technology in the field of carbon capture, or draconian government measures, which stop people using carbon. The Report sets six “critical milestones” to be met by 2020, which I will consider.

They are as follows:

1.    Renewables outcompete fossil fuels as new electricity sources worldwide

In 2017 we appear to be at the point when renewables are generally cheaper than most fossil fuels. However, the authors add that no new coal-powered power plants are being constructed and all existing coal-fired power plants are in the process of being retired by 2020. I don’t think this will happen. In July 2017 Reuters reported that, despite current energy surpluses, India’s largest power utility, NTPC Ltd, is planning on building coal plants with at least 5 gigawatts (GW) capacity. Bangladesh and Pakistan are also likely to construct new coal-fired power plants. Major economies, like Germany, still rely heavily on coal (and lignite), in 2016 23.6% of German primary energy was from coal/lignite compared to only 12.6% from renewables and 6.9% from nuclear. The other German energy sources were petroleum (34%) and natural gas (22.7%).[1] It is interesting that, despite all the publicity given to German renewables, that there was little increase in installed renewable capacity in Germany in 2016, compared to 2015.  I therefore doubt that this milestone can be achieved.

2.    Zero emissions transport is the preferred form of all new mobility in the world’s major cities and transport routes

One of the objectives to achieve this is that electric vehicles account for 15% to 20% of new car sales by 2020. Although sales of electric cars have seen a remarkable rise in the last few years, and will clearly largely replace fossil fuel cars within twenty years, sales start from a very low base, and there are insufficient models in the market as of 2017.

Global sales of the light-duty plug-in vehicle segment achieved a 0.86% market share of total new car sales in 2016, up from 0.62% in 2015 and 0.38% in 2014. To jump from under 1% of global sales to even 15% within three years is not feasible, a more realistic, if ambitious target, would be around 5% of sales by 2020. Most of the largest car makers have not geared up to produce electric vehicles on anything like the scale required, and the power infrastructure is currently inadequate to support additional vehicles in cities like London. There are large problems to be overcome before electric vehicles are the norm. In July 2017 Bloomberg New Energy Finance predicted that electric vehicles will take 54% of new car sales by 2040.[2] BNEF adds that electric vehicle sales will grow steadily in the next few years, from the record 700,000 seen in 2016 to 3 million globally by 2021. At that point, they will account for nearly 5% of light-duty vehicle sales in Europe, up from a little over 1% now, and for around 4% in both the U.S. and China. BNEF see electric vehicle sales really taking off in the late 2020’s, which is really only 10 years away. I think that because of the initiatives taken by governments, including the UK, France and Norway, to ban sales of fossil fuelled vehicles (by 2040 in the case of the UK and France) this will itself drive the market quicker than BNEF predicts. However, on current projections, it must be questionable whether electric vehicles will account for 15% to 20% of new car sales, anywhere (except in Norway, which already exceeds this target, and possibly in Estonia) by 2020. It is also important to remember that building an electric car (embodied costs) absorbs a significant amount of carbon, and that over 240,000 km (150,000 miles) the large electric car is likely to incur a carbon cost of 190g per km and the small one 47 g per km.  Electric vehicles are not carbon free; the really low-carbon forms of transport are bicycles, walking and horses.

The authors also say that heavy duty vehicle fuel efficiency will improve by 20% by 2020 – again, given the age of the fleet, this is unlikely, that may be the case for new vehicles, but trucks have a service life of at least 10 years, or over 20 years in developing countries. They also talk about “major cities decarbonizing transport fast”, but in Europe the pressures to ban diesel cars in cities are a result of the realization that “clean diesel” was a lie, and that the soot from diesel vehicles has serious health implications. There is also talk of public transport doubling its share of passenger transport, whereas the more likely development is the replacement of privately owned vehicles with shared vehicles, like Zip Car, but that’s on a longer cycle than three years.

As for a reduction in aviation emissions, aircraft have been getting more fuel efficient for years, but fleet numbers have continued to grow. Boeing forecast the global demand to 2035 is for almost 40,000 new aircraft. I also wonder how this is compatible with zero carbon emissions by 2050, surely the only way that this will be possible will be to impose very heavy carbon taxes on flights, reducing passenger traffic to very low numbers. Electric aircraft may work for light aircraft, but there is currently no viable zero-carbon technology for larger aircraft, if you exclude biofuels, which have their own serious problems, as they compete with food supplies. Shipping is also referred to, which currently accounts for 1.5% of carbon emissions, but there is as yet no clear pathway to a zero-carbon fleet by 2050.

3.    Large-scale deforestation is replaced with large-scale land restoration, and agriculture shifts to earth-friendly practices

Land use changes and industrial agriculture are major sources of carbon emissions. But the solutions proposed, reforestation and sustainable agricultural practices, while desirable, may be difficult to achieve in practice, the Brazilian Amazon is still illegally being cut down by ranchers, supported by armed gangs and there is no sign of this practice ending. In Central Africa, a NASA photograph taken in 2016 (see below) shows that widespread agricultural burning continues throughout central Africa, particularly in the southern region of the Democratic Republic of the Congo, Zambia and Angola.

We have a long way to go, and we must also address emissions from agricultural feedlots in the USA and industrial farming around the world. Again, there is currently no clear pathway to achieving zero land use and agricultural emissions by 2050.

4.    Heavy industry – including iron & steel, cement, chemicals and oil & gas – commits to being Paris compliant

The key problem is that in the preface the three scenarios shown for spending the available carbon budget all show zero emissions being reached between 2035 and 2050. But in the Report, it is stated that, “Heavy industries are …. On a trajectory to halve emissions by 2050 using science-based targets.” This is a sector which generates 32% of global emissions. If this is the case this sector will still be emitting 12.48 Gt C02 in 2050, completely incompatible with the Paris Agreement targets.

5.    Cities and states are implementing policies and regulations to fully decarbonize buildings and infrastructure by 2050

The increasing pace of urbanization, particularly in China, will generate emissions on a large-scale, the Report says, that, “Without concerted action, building the infrastructure needed by the world’s growing and increasingly urban population would generate a total of 470 Gt of CO2 emissions by 2050 – nearly 10 times the total global CO2 emissions in 2012.” Even if all new buildings are zero carbon emitters in terms of their energy requirements while in use, the quantities of steel, concrete and other materials will all have their own carbon footprint.

The Report also mentions a complete phase out of purchased electricity, however as temperatures increase with climate change, the use of air-conditioning will become essential in many parts of the world, as heat waves will be a major threat to human life, particularly in South Asia and the Middle East. Achieving decarbonized buildings by 2050 is a task of a tall order, especially when the population in so much of the developing world lives in slums, often controlled by criminal gangs.

Again, I fully applaud the objectives, but seriously doubt whether they are achievable in this timescale.

6.    Investment in climate action is beyond USD $1 trillion per year and all financial institutions have a disclosed transition strategy

There is no doubt that very large investments have been made over the past five years in renewable energy and that companies like Tesla have become attractive to investors. This is an area where much is already being achieved, but the scale of the changes required is on a scale that few truly understand. A zero-carbon economy, when we finally achieve it, will look very different from the 20th – early 21st century economy we have become used to.

The necessary investment could be disturbed by a major economic crisis, for example China is increasingly vulnerable because of its growing debt problems, and Europe will undoubtedly face a major crisis in the EuroZone in the next decades, Greece is an example of what could be a more general problem, affecting Italy and other EuroZone members. A major conflict, say over Korea, could also affect the flow of investment.

In short, considering the six critical milestones, I cannot see how they will lead to zero-carbon by 2050, as set out in Fig. 2 of the Preface. It needed a far more rigorous approach. In addition, we need to consider very heavy carbon taxes, and support new technical developments in carbon capture and storage, which may be our only hope of keeping emissions low, and of starting to reduce atmospheric carbon dioxide levels.

The paper by Raftery et al, “Less than 2˚C warming by 2100 unlikely”[3], published in Nature Climate Change in July 2017, illustrates the problems and is a warning. The authors, conclude that, “The likely range of global temperature increase is 2.0–4.9 C, with median 3.2˚C and a 5% (1%) chance that it will be less than 2 C (1.5 C).” They add, “Our model is not a ‘business as usual’ scenario, but rather is based on data which already show the effect of emission mitigation policies. Achieving the goal of less than 1.5˚C warming will require carbon intensity to decline much faster than in the recent past.” Their model predicts that “the Paris Agreement’s target of net zero emissions in the second half of the twenty-first century is unlikely to be reached.”

We must hope that emissions peak by 2020, they have been stable for the last three years, and the share of renewables has been climbing rapidly as the costs of solar PV and wind have dropped dramatically. However, industry, airlines and shipping have no easy path to a zero-carbon future, and I am cautious about being too optimistic about the speed of reductions for buildings and the urban environment. Just because a target is set down in a planning document is no guarantee that it will, or even can, be met. In many countries official corruption, or government inaction, will make achieving any targets difficult, even if Europe, and hopefully China and India, make major efforts to achieve a low carbon future.

Global warming by 2100 of the 3.2˚C predicted by Raftery et al, will have horrendous consequences, increasing heat waves in the tropics, creating droughts and hastening sea level rise. There is now a growing body of literature on the prospects of achieving the Paris Agreement targets, and a number of experts do doubt that we can meet the Paris Agreement target of 2˚C. We must do all we can to make the public aware of the level of the threat, and the and the need to start adapting to the new reality. “2020 The Climate Turning Point”, is a useful contribution to the debate that we now need to engage with, and that is how can we overcome the plans which currently appear to make achieving the Paris Agreement goals very difficult. We can no longer afford to put our heads in the sand, and we need to imagine the impossible if we wish to avoid living in a very different world.

Andrew Palmer

23rd August 2017





[3] Raftery, Adrian E., Alec Zimmer, Dargan MW Frierson, Richard Startz, and Peiran Liu. “Less than 2˚C warming by 2100 unlikely.” (2017).


About Andrew Palmer (275 Articles)
Book by Andrew Palmer explores today's fundamental & systemic problems of the world. Proposes a framework for understanding the forces that are driving change.

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