Avoiding dangerous climate change: analysis with an integrated assessment model

Lead Research Organisation: University of East Anglia
Department Name: Environmental Sciences

Abstract

One of the most important issues in climate policy over the next few years will be the choice of appropriate targets for emission reductions (known as mitigation). Article 2 of the United Nations Framework Convention on Climate Change requires stabilization of greenhouse gas concentrations at a level that would 'prevent dangerous anthropogenic interference with the climate system ... within a timeframe sufficient to allow ecosystems to adapt naturally to climate change, to ensure that food production is not threatened, and to allow economic development to proceed in a sustainable manner'. The key question therefore is the appropriate level and timescale for the stabilization. In order to best inform the choice of stabilization scenario and hence the potential targets for emission pathways, policy makers need assessments of the risks and costs associated with these alternative future scenarios. This information should also be accompanied by an extensive uncertainty analysis, which has, for the most part, not been provided to date. The risks and costs of these scenarios can be studied with computer integrated assessment (IA) models that link together component codes simulating the global economy, earth's climate system, and impacts of climate change upon human systems (e.g., water stress, agricultural yield losses, coastal flooding, human health risks , and on natural ecosystems (e.g., biodiversity, shifts in vegetation communities) and their accompanying services. The proposal centres on these types of analyses using the Community IA System (CIAS) that I have built with colleagues. The first objective of my research is to use CIAS to provide a risk assessment of the likely damages avoided, and hence the likely adaptation challenges remaining, under successively more stringent stabilization (and concurrently mitigation) scenarios, compared to a baseline 'no policy' scenario. In order to determine the pathway to a given stabilization scenario, policy makers will need information about the economic costs and technological feasibility of alternative mitigation policies. To provide this complementary information I will draw on the work of my collaborator Terry Barker at the University of Cambridge. Uncertainty analysis is key to properly performing a a risk assessment. Therefore I will assess uncertainties arising from (a) key climate model parameters through collaboration with the Hadley Centre and the Climate Prediction.net project (b) the diversity of spatial climate projection patterns arising from Global General Circulation Models (c) parameters within economic and impacts modules (d) alternative future socioeconomic scenarios and (e) use of different module codes written at different institutions. I will explore dynamic issues concerning the particular pathway towards stabilization and how impacts might be affected by temporarily overshooting of the ultimate stabilization levels being considered. I will initiate new studies of the feedbacks of climate impacts on the economy, considering both the effects of gradual climate change those of extreme weather events, breaking new ground in integrated assessment modelling. The third aim is to study the implications of land use change and its relationship with two critical elements of the human response to climate change today: (i) implications of large scale cropping of biofuels and (ii) the potential for avoided deforestation (now making up nearly 25% of global emissions) to play a major role in climate mitigation policy. The research will contribute useful information towards future assessments by the Nobel Peace Prize winning Intergovernmental Panel on Climate Change. It will be accompanied by a 2-way interaction with DEFRA to maximise policy relevance of project plans and outputs. Members of the UKCIP08 User Group will also be consulted. Information will be disseminated also via journal papers, UNFCCC side-events, and 2 stakeholder workshops.

Publications

10 25 50
 
Description An analysis of peer-reviewed published studies that project ecosystem changes resulting from projected local or global climate changes, showed that dramatic and substantive projected increases of climate change impacts upon ecosystems are projected to occur with increasing annual global mean temperature rise. It was found that substantial negative impacts are commonly projected as temperatures rise globally by more than 2_C compared to pre-industrial times, especially in biodiversity hotspots. Compliance with the ultimate objective of the United Nations Framework Convention on Climate Change requires that climate change be reduced so that ecosystems should be able to adapt naturally. Hence unless global temperature rise is kept below 2_C at most, it will be difficult to achieve this unless great efforts are made to reduce greenhouse gas emissions and to reduce tropical deforestation.



More generally many countries have proposed limiting global warming to 2°C above pre-industrial levels. The UN Framework Convention on Climate Change is currently assessing options for including the reduction of emissions from deforestation and degradation (REDD) in future climate agreements. Land use change (LUC) currently contributes ~17% of global anthropogenic greenhouse gas emissions.The study showed that avoiding deforestation has a critical role in the ability to constrain global temperature rise to 2C above pre-industrial levels. We show that if strong policies for avoiding tropical deforestation are not implemented, society's best efforts to limit warming to 2°C, are jeopardized, even in the presence of some of the strongest measures being contemplated to reduce greenhouse has emissions from the burning of fossil fuels such as coal and oil. Emission reduction rates that otherwise appear to constrain global mean temperature rise to 2°C would have to be doubled in order to maintain the same chance to meet the temperature constraint, if current rates of deforestation continue. Near total avoidance of tropical deforestation (e.g., through REDD policies) is thus a key component for achieving stringent temperature targets.



The study also considered a world in which temperatures have risen by 4_C and compared it with a world in which temperatures have risen by 2_C. It identified an urgent need to consider how risks interact in a 4_C world, especially because ecosystem services that support prosperity would be declining in a 4_C world. A 2_C world is projected to experience about one-half of the climate change impacts than a 4_C world, and ecosystem services, including the carbon sink provided by the Earth's forests, would be expected to be largely preserved. But if biofuels are used to reduce emissions of greenhouse gases, demands for land and water for biofuel cropping could reduce the availability of these resources for agricultural and natural systems. Hence, it is very important that analyses consider how all these factors interact.



Climate change is expected to cause significant changes in the future distribution of rainfall. There is an expectation of drying in southern Europe and wetting in northern Europe, with some regions such as southern UK experiencing drier summers and wetter winters. With no reduction in greenhouse gas emissions, very large increases in drought are projected for southern Europe. However, if emissions are reduced so that CO2 concentrations in the atmosphere stay below 450 or 400 ppm, the study projects that there would be very large reductions in both drought frequency and in total months of drought which would otherwise be experienced during 2050 to 2099.

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Integrated assessment models (IAMs) have commonly been used to understand the relationship between the economy, the earth's climate system and climate impacts. They are frequently applied to determine 'optimal' climate policy by balancing the costs of climate policy against valuation of the benefits. It was found that one of the models, FUND, underestimated the reduction in warming that results from reducing emissions of greenhouse gases, showing that this model will underestimate the benefits of emission reductions and hence the calculated 'optimal' level of investment in mitigation.
Exploitation Route The AVOIDing dangerous climate change project has been used to inform the position of the UK government in the UN Framework Convention on Climate Change negotiations Much of this research has been disseminated to UK government stakeholders through the AVOIDing dangerous climate change project (www.avoid.uk.net)
Sectors Environment

 
Description The AVOIDing dangerous climate change project has been used to inform the position of the UK government in the UN Framework Convention on Climate Change negotiations Much of this research has been disseminated to UK government stakeholders through the AVOIDing dangerous climate change project (www.avoid.uk.net)
First Year Of Impact 2011
Sector Environment
Impact Types Policy & public services

 
Description I acted as Lead Author for the Climate Change Risk Assessment 2 (CCRA2) for the Climate Change Committee
Geographic Reach National 
Policy Influence Type Membership of a guideline committee
URL https://www.theccc.org.uk/tackling-climate-change/preparing-for-climate-change/climate-change-risk-a...
 
Description Member of Task Group on Data and Scenario. Support for Impact and Climate Analysis (TGICA)
Geographic Reach Multiple continents/international 
Policy Influence Type Membership of a guideline committee
URL http://www.ipcc.ch/activities/tgica.shtml
 
Description EU Framework 7
Amount £1,100,000 (GBP)
Organisation European Commission 
Sector Public
Country European Union (EU)
Start 11/2013 
End 10/2017
 
Description EU Framework 7
Amount £423,000 (GBP)
Organisation European Commission 
Sector Public
Country European Union (EU)
Start 12/2010 
End 11/2013
 
Description EU Framework 7
Amount £239,260 (GBP)
Organisation European Commission 
Sector Public
Country European Union (EU)
Start  
 
Description European Calculator
Amount £5,000,000 (GBP)
Funding ID 730459 
Organisation European Commission H2020 
Sector Public
Country Belgium
Start 11/2019 
 
Description OMII UK
Amount £82,000 (GBP)
Organisation OMII-UK 
Sector Academic/University
Country United Kingdom
Start  
 
Description Understanding the Pathways to and Impacts of a 1.5°C Rise in Global Temperature
Amount £100,000 (GBP)
Funding ID NE/P014992/1 
Organisation Natural Environment Research Council 
Sector Public
Country United Kingdom
Start 11/2016 
End 10/2017
 
Title Community Integrated Assessment System 
Description Understanding how greenhouse gas emissions create climate change impacts 
Type Of Material Model of mechanisms or symptoms - human 
Year Produced 2010 
Provided To Others? Yes  
Impact The system has been extended and used for research by other institutions. 
URL http://ermitage.cs.man.ac.uk
 
Title Community Integrated ASsessment System 
Description Links together models from different institutions and disciplines to provide insights about future climate change scenarios 
Type Of Material Computer model/algorithm 
Year Produced 2010 
Provided To Others? Yes  
Impact Publications 
URL http://ermitage.cs.man.ac.uk
 
Description Engagement with World Wildlife Fund 
Organisation World Wide Fund for Nature
Country Switzerland 
Sector Charity/Non Profit 
PI Contribution We held a joint workshop with WWF; we present the research results from the IMPALA project. We also completed a consultancy project for WWF during 2015-2016
Collaborator Contribution They hosted the workshop. They funded the consultancy project.
Impact A publication, Warren R, Price J, VanDerWal J, Cornelius S, Sohl H. (2018). The implications of the United Nations Paris Agreement on climate change for globally significant biodiversity areas. Climatic Change.
Start Year 2016
 
Description Wallace Initiative 
Organisation James Cook University
Department Centre for Tropical Biodiversity and Climate Change
Country Australia 
Sector Academic/University 
PI Contribution Provided climate change data, and guidance on its use Participated in collaborative research to coproduce a publication
Collaborator Contribution Ran biodiversity computer models Participated in collaborative research to coproduce a publication
Impact Publication (See publication list) Multi-disciplinary (climate change science, ecology)
Start Year 2010
 
Title ClimaScope 
Description Data from my project was placed in a software tool available on line 
Type Of Technology Webtool/Application 
Year Produced 2012 
Impact ClimaScope won the work bank Large Organisation Recognition Award for Apps for Climate. ClimaScope was developed by Dr Jeff Price at Tyndall Centre using data provided from my project. 
URL http://climascope.tyndall.ac.uk/
 
Description Led Tyndall Centre contribution to two major Avoiding Dangerous Climate Change Projects for Dept of Energy and Climate Change 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Policymakers/politicians
Results and Impact Entire research programme, it produces reports and disseminate through organised communication and outreach. In particular I provide information about climate change impacts and how mitigation can reduce these. This was a formal consultancy arrangement.

Secretary of State has stated formally that project has informed UK climate policy making. For example, the project informs UK government prior to its participation in each of the UN Framework Convention on Climate Change Conferences of the Parties.
Year(s) Of Engagement Activity 2009,2010,2011,2012,2013
URL http://www.avoid.uk.net
 
Description UK Dept of Business and Industrial Strategy 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Led climate change impacts assessment and communicated outcome to BEIS as part of formal consultancy project.
Year(s) Of Engagement Activity 2017,2018