Professor Andy Kerr is founding Director of the Edinburgh Centre for Carbon Innovation (ECCI), Policy Director for  ClimateXChange, established by the Scottish Government to support delivery of their world-leading climate and energy targets, and Professor of Low Carbon and Climate Innovation at the University of Edinburgh. Here he blogs on the IPCC’s latest report, published on 8 October 2018, on limiting warming to 1.5 degrees.

Limiting global warming to 1.5°C requires “rapid and far-reaching transitions in energy, land, urban, infrastructure (transport and buildings) and industrial systems…unprecedented in terms of scale…”. That’s one of the key findings of a landmark report published this week by the UN Intergovernmental Panel on Climate Change (IPCC).

The landmark report assesses the likely impacts of global warming of 1.5°and 2°C above the pre-industrial era. It considers what pathways society can take to meet the 1.5°C target and the extent to which we are on track with existing commitments.

Its findings are perhaps not surprising. It sets out, in stark detail, the effects that increases of 1.5ᵒC or 2ᵒC are likely to have on people, wildlife, ecosystems and economies over the coming decades. The more global temperatures rise above today’s temperatures towards 1.5°C and 2°C, the greater the likelihood of extreme weather events and systemic environmental change posing risks to our health, wealth and livelihoods.

Populations at high risk of adverse impacts with 1.5°C warming include vulnerable and disadvantaged people, some indigenous peoples and local communities dependent on agriculture or coastal livelihoods. And if temperatures increase by 2 rather than 1.5°C the report finds, for example, that several hundred million more people will be exposed to climate risks. Projections of the impacts on unique and threatened ecological systems suggest precipitous decline: for example, 70-90% of the world’s warm water coral reefs will be lost with 1.5ᵒC of warming, and completely lost under a 2ᵒC warming.

At the heart of the report is the identification of greenhouse gas emission pathways that are necessary for global society to reduce the most adverse climate risks and to adapt to the changing climate. To meet the 1.5°C target without overshooting (i.e. without ending up with higher temperatures and then reducing them later in the century), carbon dioxide emissions need to be reaching net zero by about 2050, and rapid reductions need to start now. If we accept the risk of overshooting, then rapid reductions in emissions need to have started by 2030, but we then rely on heroic assumptions about the use of technical solutions (such as aggressive carbon dioxide removal using carbon capture and storage technologies) later in the century.

So what does this all mean in practice? Globally, we need to see far-reaching transformations in energy production and use, in buildings and transport infrastructure, and in land use.

Perhaps a more useful question from this report is to ask what Scotland can do to support global efforts to meet this target. There are two possible actions.

The first is to lead by example. Scotland can demonstrate that it is possible for a country with an advanced economy to make rapid, systemic reductions in greenhouse gas emissions, whilst continuing to deliver a sustainable, prosperous and inclusive economy. Indeed, Scotland is widely lauded for achieving 70% of its electricity generation from renewables and for making substantial emission reductions to date – a drop of nearly 50% compared with 1990 levels – all whilst continuing to generate positive social and economic outcomes.

In the short term, this means delivering policies already announced by the Scottish Government to meet the emission reduction targets set through to 2032. These include ending the need for petrol and diesel cars and vans, transforming the energy efficiency of our building stock and increasing the use of low carbon heat as well as dramatically increasing the number of trees planted and improving agricultural practices.

The Scottish Government has proposed new climate legislation which will make Scotland’s long term target (to 2050) more challenging – a 90% greenhouse gas emission reduction rather than an 80% target. While there will be much debate about this long term ambition, whether it is aggressive enough and the political signals it sends, the more urgent issue is ensuring that Scotland delivers the transformative changes needed in the next 5-10 years.

The second way in which Scotland can support global efforts is as a knowledge exporter. Scotland can develop the know-how – the new knowledge, products and services – which countries around the world need to help them deliver similar rapid emission reductions. Scotland has produced some of the transformative thinkers and innovators of modern history. We need to do so again.

This emphasises the value of Scotland’s entrepreneurial CanDo initiatives. And the work we do at ECCIwith our European Climate-KICpartners to enable systemic innovation from early stage business ideas to public policy, public authoritiesand city-region innovation and practice. For example, Edinburgh is hosting the global finals of the world’s largest green business ideas competition – ClimateLaunchPad– next month. And we are working with the City of Edinburgh to support plans for transforming the City Centreover the next few years.

This IPCC 1.5°C report is a clarion call for change to reduce the risks of the increasingly adverse effects of unmanaged climate change. But it also offers a view of a route-map for cities, states and regions to transform to become more climate resilient and to support wider sustainable development goals for society, the economy and the environment. Scotland is well placed to lead this transformation.

The Scottish Government has published a draft Climate Change Plan setting out how Scotland can achieve our carbon reduction targets in the period up until 2032.

ClimateXChange Directors Dr Andy Kerr and Prof. Pete Smith have both given evidence to Parliamentary committees as part of their scrutiny of the draft. Below is the written submission from Policy Director Andy Kerr and CXC Manager Ragne Low to Parliament in response to the draft plan.

Written Evidence to ECCLR Committee on Draft Climate Change Plan

This submission sets out our views on the key issues for the draft Climate Change Plan (dCCP) under nine themes.

1. Progress to date

Carbon emissions arising from electricity generation in Scotland have fallen sharply following the closure of 3.5GW of coal generation plant at Cockenzie (2013) and Longannet (2016). Although firm evidence is not yet available, research suggests that this has been achieved at the cost of a reduction in the overall volume of generation in Scotland and in the amount of time that Scottish generation exceeds Scottish demand (although this is still high). Assumptions about further decarbonisation of the Scottish electricity system must be grounded in this reality and the fact that there is an increasing interdependence between the Scottish electricity system and that of the rest of GB (see below for the implications of this).

The transport sector has lacked progress in emissions abatement since 1990, with vehicle efficiency improvements offset by demand increases.

In forestry, rates of woodland planting have not been in line with targets, casting some doubt on whether the rapid increase in planting described in the dCCP can be achieved (see below).

2. Scale of reductions proposed

The reductions proposed depend upon certain assumptions about deployment rates and reducing costs. Over time, the more uncertain assumptions underpinning options in the dCCP will become better understood and characterised. For example, the evidence base is still developing in some key areas such as low carbon heating, and some technologies are yet to be proven at scale. Thus whilst the scale of reductions proposed is appropriate overall, the particular division of effort across sectors may prove to be ill-founded and require revision. Furthermore, the achievability of many dCCP policy outcomes depends upon sustained effort, partnership building and a high degree of technical and social innovation.

For electricity, the dCCP assumes zero-carbon and then carbon-negative Scottish generation. The role Scotland plays in the wider GB synchronous electricity system appears to be underplayed here, and there is a risk that this Scottish-system emphasis could undermine the role of the Scottish system in decarbonising the wider GB electricity system. A further risk is the heavy reliance on negative emissions electricity by 2027 as a route to meeting Scotland’s overall carbon reduction ambitions, which would be seriously undermined should new conventional generation become desirable (for wider systems reasons) before CCS is viable at scale. Costs and capabilities for future CCS plant remain deeply uncertain.

For transport, with internal combustion engine vehicles expected to comprise the majority of the fleet out to 2032, it is reasonable to concentrate the main abatement effort on technical improvements to the carbon efficiencies of these types of vehicles. However, research has shown that car emissions under real-world driving conditions tend to be significantly higher than those reported in the official tests and this differential could lead to an overestimation of the abatement potential attributed to transport Policy Outcome One. In addition, the global transport sector is undergoing radical, disruptive changes through a combination of data driven and technical innovation and social pressures. This may well speed up the rate at which we see change in Scotland, but this process will involve close partnership with local authorities (for example if cities start to ban diesel vehicles in the late 2020s as is already planned in other European cities).

In agriculture, the UK CCC’s call for agroforestry development to support agricultural emissions reduction has not been explicitly taken up. Mention is made of exploring how best to increase tree planting on farms. This should include trialling more innovative approaches, such as payments for carbon sequestration.

3. Appropriateness of the timescales

The carbon envelope for residential and non-domestic buildings emissions is highly ambitious but also irregular, with little change before 2025, then steep reductions in the seven years to 2032. This implies a very rapid switch-over in heat supply away from gas and the proportion of heat supplied from low carbon sources (from 18% to 80% of domestic buildings and 65% to 94% of non-domestic buildings). Over the short term, a period of exploration and demonstration on low carbon heat supply is welcome, given uncertainties about preferred options, costs and realistic deployment rates. However, the scale and pace of the proposed infrastructure poses and number of questions about delivery and feasibility (not least in terms of social acceptance).

The corresponding reduction in heat demand (only 6% by 2032 for the residential sector and 10% for the non-domestic sector) seems rather low, given the ambitions of the Scottish Energy Efficiency Programme (SEEP) and demand-response initiatives. It would be interesting to understand better the analysis behind these forecasts (see section 9).

In transport, there is an assumption of very rapid increases in electric vehicle uptake – over 100% in this year alone and with annual increases of up to 25%. It is very difficult to judge the appropriateness of the timescales set out here (see also section 9).

The very challenging, early escalations in afforestation and peatland restoration rates raise questions around deliverability, including whether the much more limited progress achieved to date through schemes such as Peatland Action can be scaled up rapidly enough and whether private capital can also be brought to bear through payment for ecosystem services mechanisms. To achieve the very ambitious, sustained annual targets on peatland restoration in particular will be costly, and the resources required to maintain restored sites and monitor their carbon performance over time also need to be factored in.

4. Considerations of behaviour change and opportunities to secure wider benefits

Although smart meters are mentioned in the ResidentialServices and Industry chapters, the ambition appears to be limited and there is no discussion of their use in facilitating systematic Demand Side Management and Response for electricity or heat.

Transport shows a reliance on mostly technology-based measures, with demand side measures largely peripheral in terms of significant emissions reductions. This suggests the need for further consideration of more ambitious demand-reducing and behavioural measures, given their considerable co-benefits for social inclusion, health and wellbeing and liveability in urban areas.

Overall, whilst mention is made of the very useful and well-founded ISM tool, it is unclear how far the tool was used consistently across the policy development process. The TIMES framework assumes a certain rate of uptake of technologies by households and businesses and it is important to stress-test these using good social science research on social practices and behaviours to understand how these may constrain or support technology-based assumptions. It does not appear that there was time to do this in the development of the dCCP; this will be important to address as we move forward.

Wider benefits can be expected from the forestry policies in terms of income to rural communities from sustainable wood production as well as potentially positive environmental impacts if woodland creation is managed sustainably. Innovative new timber products, and the growth of sectors such as offsite timber construction, offer cross-sector benefits for deploying affordable, energy efficient homes in Scotland and abroad.

Overall there is now ample evidence of the wider benefits that can reasonably be claimed for mitigation policies. There is a need however to test those assumptions against specific policies in Scotland, to understand how wider benefits can best be maximised.

5. Governance

The proposals for governance and oversight are to be welcomed. It will be important that the governance body is independent and that it contains a range of interested stakeholders. To be effective it must be able to make recommendations and have – and be seen to have – a scrutiny function. This new body will need to work closely with, and establish its relationship to, the UK CCC.

The dCCP is necessarily prescriptive, being based on a whole systems approach underpinned by the TIMES model, which models one pathway – that of least overall cost to society – to achievement of Scotland’s statutory targets. However, as technologies are deployed in the real world and as costs either follow or not projected downward trajectories, there will be a need to ‘ground truth’ the scale of the reductions proposed. In turn, the whole-system knock-on effects of these realities will need to be calculated. A sophisticated monitoring & evaluation and governance framework will be needed to ensure this is done systematically and transparently (see also section 9).

6. Wider dependencies

The dCCP appears, conceptually at least, to isolate the Scottish electricity system and treat it as separate from the GB system. However, under present arrangements, the role of intermittent Scottish renewables in the system depends on the running of significant capacities of fossil fuel generation in rGB to provide services important to reliability and resilience. Engagement with the UK Government, Ofgem, National Grid and the Distribution Network Operators will be needed to ensure that Scotland’s low carbon electricity ambitions are taken forward in a way that best supports GB-wide electricity decarbonisation. In addition, the wider deployment of embedded local electricity generation technologies (e.g. solar) to match local demand – for example in new housing developments as technology costs continue to fall through the 2020s – will lead to substantially different modes of electricity transmission and distribution in Great Britain, which will require a whole-GB response.

The dCCP’s alignment with the UK Government’s forthcoming Emissions Reduction Plan needs careful consideration, in particular as many strategic areas of energy policy are reserved, and the cost, price and performance of low carbon technologies are often settled internationally. A clear example is the reliance in the dCCP on bioenergy-based CCS, a technology yet to be proven at scale and which will depend heavily on support UK Government, EU and international support. (Though there may be opportunities for the Scottish Government to support industrial and smaller-scale CCS initiatives).

Brexit is also clearly of relevance in terms of future technology costs to Scottish households and businesses, and of electricity interconnection.

7. Partnership

Every policy outcome in the dCCP depends upon partnership for its achievement. Local authorities, land owners and managers, commercial building owners and occupiers, public bodies, businesses and community and third sector organisations are all critically important stakeholders. The extent to which the ambitions set out in the Plan are realised will follow directly from the strength of the partnerships built to support roll out of policies and conversion of proposals into firm policies. This is not as clearly specified in the dCCP as it should be.

8. The TIMES model

The shift to more integrated analysis and modelling to underpin the RPP is welcome. Compared to RPP2, there is greater consistency of format and presentation in the sectoral chapters, which again is very welcome.

The TIMES model generates a pathway that represents the least cost solution to meeting a particular carbon target, whilst satisfying a particular set of demands. The outputs of the model are highly contingent on the input assumptions, many of which are uncertain. However, there is little in the dCCP that explains how such uncertainties were taken into account, or indeed how the outputs from TIMES were interpreted.

9. Transparency

This lack of explanation about how outputs from TIMES were used is understandable from the perspective of the time available to Government before publication of the dCCP. However, greater transparency now that the draft Plan is public and the TIMES model runs complete is highly desirable. For example, it would be useful to see how officials and Ministers interpreted the optimal TIMES pathway and sector envelopes, and reconciled these with real world constraints in order to produce policies and proposals.

Transparency would be welcome also on the assumptions that have gone into the modelling and decision making process. To take one example, in transport, the year-on-year rates of expansion of the EV market are highly ambitious – as high as 25% for some years. These rates are predicated on assumed improvements to the cost and performance of EV batteries, which may well be reasonable but are not set out in the dCCP and therefore cannot be scrutinised.

There is also a need to differentiate between sectors where supporting evidence is relatively robust and consistent (e.g. the increasing affordability of large-scale offshore wind) and other areas where there is still considerable uncertainty and variability in the evidence base (e.g. on low carbon heating supply technologies).

Andy Kerr

Co-Director, Centre of Expertise on Climate Change (ClimateXChange) &

Executive Director, Edinburgh Centre for Carbon Innovation (ECCI)


Ragne Low

Programme Manager, Centre of Expertise on Climate Change (ClimateXChange)

We gratefully acknowledge the expert views provided by members of the ClimateXChange (CXC) research community that have helped shape this submission, in particular those offered by scientists from the James Hutton Institute and the Universities of Edinburgh, Strathclyde and Leeds. However, the views stated above are our own, and any errors remain ours.

See the official reports from the ECCLR Committee and the REC Committee on the Scottish Parliament website here and here