Global scale impacts of climate change: a multi-sectoral analysis

Lead Research Organisation: University of Reading
Department Name: Sch of Agriculture Policy and Dev


Climate policy should be informed by robust and credible information on the impacts of climate change across the global domain; a global perspective also places local and regional impacts in context, and helps identify potential 'hotspots' for further scientific investigation. The project assesses the global-scale impact of climate change using a range of linked impact modules and impact indicators, representing impacts on water resources, flood risk, food production, biodiversity and human health and well-being on land, at the coast, and at sea. The project will synthesise and aggregrate across sectors and regions, using a variety of approaches, and allow the identification of the risks of specific impacts occurring at different rates of climate change. The methodology and results of the project also provide a framework for the assessment of the impacts of defined climate policies. First, it allows detailed geographically-explicit assessments of specific climate scenarios or climate policies, using the suite of linked models. Second, it allows the more rapid assessment of a very large number of climate outcomes (based for example on a probabilistic assessment of the climate effects of an emissions policy) using regionalised functions relating climate impact to indices of climate forcing. The project will be undertaken by a consortium of twelve lead partners, all with international reputations in the field of climate impact assessment.
Description The two broad aims of the project were to (i) assess the implications of different rates and amounts of climate change for a wide range of impacts across the global domain, and (ii) develop a framework for the assessment of impacts under defined climate policies. The project assessed impacts across the global scale using a range of indicators covering water resources, river and coastal flooding, agriculture, terrestrial and aquatic ecosystems, and health. It used scenarios constructed from up to 21 climate models, with four emissions and socio-economic scenarios. The study provides (often for the first time) quantitative indications of the potential impacts of climate change, together with associated uncertainties. There are a number of more general conclusions, based on results from across the scenarios and sectors.

(i) The impacts of climate change may be very substantial, even for small increases in global mean temperature or by the 2020s, but these impacts vary regionally with the projected change in climate.

(ii) There is considerable uncertainty in estimated impacts, with different amounts of uncertainty for different sectors and in different places. For example, the uncertainty in impacts which are largely a function of temperature or sea level rise is considerably smaller than the uncertainty in impacts which are driven by changes in precipitation. There is a large difference between climate models in projected changes in rainfall across south Asia, and this translates into large differences in impacts on water resources, floods and crop productivity not only at the regional scale, but also when aggregated to the global scale.

(iii) There is little clear evidence of major thresholds in the shape of the relationship between climate forcing and impact.

(iv) Improved characterisation of socio-economic vulnerability (such as in the health models) shows that climate change will still have significant impacts on health (e.g. malnutrition or vulnerability to drought) even when economic development is taken into account, and that socio-economic factors can either amplify or dampen the effects of climate change, depending on context.
Exploitation Route The methodology and results are relevant for global-scale climate change risk analyses, which may be undertaken by government, development agencies, security agencies and multi-national businesses. One of the aims of the QUEST-GSI project was to develop a framework to allow the assessment of the impacts of climate change under specified emissions policies, to support climate policy development.

During 2009 DECC initiated a major research programme (AVOID) to produce policy-relevant evidence on the risk and consequences of "dangerous" climate change, and on measures to avoid such change. The successful consortium, led by the Met Office Hadley Centre and including the University of Reading, based part of its proposal on the QUEST-GSI project methodology, and the methodology was subsequently used to estimate the impacts avoided by a set of specific policy-relevant emissions policies. The health models (coastal flood mortality and malnutrition models) were used in the WHO's global health risk assessment of climate change, coordinated by LSHTM.
Sectors Environment

Description The research results from the QUEST-GSI project have been used by DECC to inform their views on the global-scale impacts of climate change, and provided the basis for the assessment of impacts under specific climate policies in the AVOID and AVOID2 programmes. The methodology was also used in the FCO-supported report on 'Climate Risks' led by Sir David King in 2015. The research results have subsequently been the basis of further research into the impacts of climate change at the global scale, which has been used by DfID, BEIS and the Cabinet Office.
First Year Of Impact 2013
Sector Energy,Environment
Impact Types Policy & public services

Description Influence on UK climate policy negotiators
Geographic Reach Multiple continents/international 
Policy Influence Type Citation in other policy documents
Impact The paper (Arnell et al., 2013) has been used by DECC to support its position on climate change temperature targets. The paper describes the impacts avoided by different climate change pathways, and was produced during the DECC-funded AVOID project which built upon QUEST-GSI. Subsequent research based on QUEST-GSI has been used by DECC to inform its position during the 2015 COP21 Paris climate negotiations.
Description AVOID
Amount £800,000 (GBP)
Organisation Department of Energy and Climate Change 
Sector Public
Country United Kingdom
Start 03/2009 
End 03/2013
Description AVOID2
Amount £1,450,000 (GBP)
Organisation Department of Energy and Climate Change 
Sector Public
Country United Kingdom
Start 03/2014 
End 03/2016
Description Impacts of climate change
Amount £31,500 (GBP)
Organisation Committee on Climate Change (CCC) 
Sector Charity/Non Profit
Country United Kingdom
Start 03/2015 
End 06/2015
Title QUEST-GSI global impacts 
Description The QUEST-GSI project produced estimates of the impacts of climate change across a range of metrics at gridded (0.5x0.5o) and regional scales. The gridded data are available through BADC, and the regional data are provided as Supplementary Material in published papers. 
Type Of Material Database/Collection of data 
Year Produced 2014 
Provided To Others? Yes  
Impact None yet 
Description Groundwater, Climate Change & Adaptation 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Policymakers/politicians
Results and Impact Lead presentation at a side event at COP15 in Copenhagen

Year(s) Of Engagement Activity 2009