Interview with the author (Jim Skea)

The next 10 years are key to limit the temperature increase to 1.5°C.

Jim Skea, Co-Chair, Working Group III, Intergovernmental Panel on Climate Change (IPCC)

Interview Date: 17 October 2018/ Location: Imperial College London (London, UK)

Kainuma: In October 2018, the Summary for Policymakers of an IPCC Special Report on “The impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty” (hereafter referred to as SR1.5) was approved at the 48th Plenary of IPCC in Incheon, Republic of Korea. First of all, could you please give us the implications of the 1.5°C Special Report from historical, scientific and political viewpoints?

Skea: There are three significance points to be made about the SR1.5. First of all, I think that the SR1.5 is one of the most important reports that the IPCC has produced. That is evident from the fact that there was great deal of media coverage and expectations. And the fact that the invitation came from United Nations Framework Convention on Climate Change and will be introduced to the COP24 and Talanoa dialogue at Katowice, Poland. From that point of view, it is really important. I think it’s a landmark report from IPCC.

These are two major things. I think from a scientific perspective, it can be made from IPCC groups collaborating with each other, absolutely in an unprecedented way.

The other point is that the literature had to be quite hurried because two years ago there wasn’t really any targeted literature on 1.5°C. So experts have to work hard. Especially Integrated Assessment Modelers worked very quickly.

During this time, various papers including integrated assessment models were published, and it was pointed out that the research made great progress. As a result, we were able to issue a message that there was a significant difference between 1.5°C and 2°C.

In addition, using the integrated assessment model, it was indicated that it is necessary to take measures within 10 to 15 years. In other words, if it is not possible to take measures within 10 to 15 years, net zero will not be reached by 2050. I think that is of great significance. This is the message which also leads to the sixth Assessment Report of the IPCC.

Kainuma: Do you mean the next 10 years is key to limit the temperature increase at 1.5°C?

Skea: That's right.

Kainuma: According to the integrated assessment model, CO2 emissions have to be reduced to almost zero by 2050 in order to meet the target of 1.5°C. This is not an easy task. The SR1.5 calls for “systematic transitions”. What kind of policy do you think is necessary to proceed the "transition"?

Skea: All kinds of policies. It’s just a level of ambition. You can just go through the standard list. You know carbon pricing, regulation, information and all the rest of it. What is really important is policy packages to bring policies together. Policies complement each other.

For example, if you store carbon geologically, some people needs economic incentives. We need carbon pricing as a public policy. Otherwise people may not do it. But if you look at things like efficiency standard and buildings, the carbon pricing is not the way to do that. You need regulation. You need tailor-made policies for sectors.

You need policy stability so that people in the private sector, know that if you make investment now, policies supportive will still be there in 5 to 10 years’ time. Because too much changes of policies, it means people don’t trust the policy and increase the cost of capital. Because more risk is associated to that. So institutional stability and policy stability are the most important things. Even if it’s not a perfect policy, making the policy stable is much more important.

Kainuma: Japan has a target to reduce greenhouse gases emissions by 80 % in 2050 compared to the1990 levels. It’s already a major challenge. But to follow the 1.5°C target, we need to achieve net zero emissions. It’s a more ambitious target. How can we achieve such target?

Skea: It depends on net zero CO2 or net zero GHGs. For net zero GHGs, we need negative CO2 emissions, because there is no scenario that shows non-CO2 emissions are going to zero. You need negative CO2 emissions to achieve net zero GHG emissions.

Carbon Dioxide Removal (CDR) is a part of the picture. That’s one area we need to start change. However, before going into large scale CDR, we need to do all other things more quickly and more ambitiously.

Kainuma: Can I have your opinion about Solar Radiation Management (SRM)?

Skea: As for the issue of SRM, if you look at the literature, most of it is hypothetical, in terms of theoretical kinds of experiments. Nobody has actually done real experiments. There are also the legal and ethical aspects of SRM. Whether you should do experiments in the first place makes it particularly difficult. It has regional effects. If one country actually carries this out on a large scale, and later for some reason stops it, the temperature goes up very quickly. Even if you experiment with it, there are ethical issues which make it challenging.

Kainuma: Regarding "transition," I think it is also important to change individual behavior. This is also a difficult challenge to put into practice, even if we know the importance. Do you have any suggestion about behavioral change?

Skea: You can see a weakness in the 1.5°C report. The scenarios or pathways covered by integrated assessment models assume behavioral change in some cases, but they don’t say how they will actually come about. The report is weaker on the practical policies on the behavioral changes. You need to start and make it in the short-term. That’s why we have got a new chapter in the 6th Assessment Report on short-term mitigation aspects. This is literature that the IPCC had not really assessed. IPCC has been strong on physical science and technology of climate change. We have had greater involvement by social scientists in the 6th Assessment Report.

Kainuma: In the UK, have you already discussed about the temperature increase of 1.5°C?

Skea: Not yet. The long-term goal submitted by the UK to the UNFCCC is consistent with the 2°C goal. On the other hand, in April this year, the UK Climate Change Commission (CCC) was asked to give advice by the UK government when the SR1.5 would be released. The document shown here (a letter for which the UK government asked the CCC to consider the transition path in line with the SR1.5 ) was issued right after the publication of the SR1.5.

Kainuma: How is the current situation of nuclear power generation in the UK? I think that the cost of nuclear power generation is rising now, and it is not always a price competitive situation.

Skea: The price of electricity by newly established nuclear power plants set between EDF (power company) and the UK Government was just over GBP 90 per megawatt hour.
For offshore wind, auctions came about GBP 60 per megawatt hour, so that the nuclear plant is 50% more expensive than the offshore wind, neglecting integration costs which are bigger for offshore wind. It’s certainly not higher than GBP 30 per megawatt hour.

Kainuma: In Japan, too, the importance of regional power generation has recently been recognized, and the share of renewable energy has increased.

Skea: Nuclear and renewables compete almost directly with each other. When the price gap between nuclear and renewables is decreased, and renewables become sufficiently competitive, how to supply power in more stable manner will be the next challenge. Also, towards realising low-carbon / decarbonised societies, how to overcome this challenge will be key for us.

Kainuma: Speaking of prices, the liberalization of electricity retailing began in April 2016 in Japan. How about in the UK?

Skea: We did it in 1990s.

Kainuma: The 1990s! 30 years ago. Lastly, please tell us what kind of research will become important and urgent in the UK.

Skea: We do need all kinds of research. There are big challenges in household heating and transportation. And we need to start thinking about land management and all carbon dioxide removal issues.

Kainuma: Thank you very much.