International Association for Impact Assessment

Climate Change Mitigation and Adaptation

Edited By: Loreley Fortuny

Overview & History

Mitigation involves the reduction in emissions of any greenhouse gases that contribute to climate change. Carbon dioxide is generally used as the base case to which all other gases are compared, as is the case with carbon offset programmes. However, methane, for example, contributes to climate change much more per molecule than carbon dioxide. Adaptation involves responding to the changes induced as a result of climate change. Adaptation can be reactive or anticipatory. Where possible, anticipatory actions will provide the most cost-effective response to reduce risk. Impact assessment can play an important role in identifying both potential contributions to greenhouse gas emissions and possible adaptation responses to climate change.

The contributions to and effects of climate change are by no means evenly distributed around the world. Prosperous countries are major contributors to greenhouse gas emissions, particularly through transportation and energy production, whereas the impacts of climate change are frequently felt more strongly in developing countries which may have less ability to respond to the changes. The magnitude of change also differs geographically with polar regions experiencing the greatest amount of change in the physical environment.

EIA, both project-related and strategic, and HIA are used globally as tools to assess climate impacts on projects and policy/programmes, as well as the effects on climate on populations and communities. They represent one of the few standardized global tools available to incorporate the effects of climate change into design of projects, programmes and policies by forecasting the resulting changes of baseline and future conditions. At the same time, the methodology of the impact assessment process must evolve to better incorporate these climate change-related environmental impacts.

Historically, environmental health concerns have focused on toxicological or microbiological risks to health from local exposures. However, the scale of environmental health problems is increasing as a result of climate change, and various larger-scale environmental hazards to human population health have begun to appear. Changes in the IA methodology to incorporate climate change need to begin within different jurisdictions and different climate regimes in a consistent way. At the same time regulatory bodies, governments and IFIs need to support and monitor these evaluations and be ready to incorporate them in their assessment and evaluation processes. Revision to and evaluation of IA methodology should include key risk analysts from, for example, real estate, bank and insurance industries to ensure that risk assessment methodologies conform to industry standards. 

The IA methodology can be summarized generically into:

  • issue scoping,
  • selection of valued environmental/socio-economic components and indicators,
  • assessment of impacts,
  • quantification of significant impacts,
  • development of mitigation and effects monitoring plans,
  • reporting of residual impacts and conclusions.

Terminology may differ but these basic elements, including the quantification of impacts and determination of significance, are common world-wide. This provides a consistent framework for the evaluation of environmental and socio-economic impacts associated with environmental change.

To date, incorporating climate change into the EIA process has focused on identification of mitigation elements within the project or programme scope and potential effects of climate change on the physical foundation of the project or programme. Since mitigation has been an accepted requirement for policy and project review globally following the general adoption of the Kyoto Protocol, most EIA jurisdictions require some identification of how the project or programme will affect GHG emissions. A number of guides are available to assist in formulation of GHG contributions from various types of projects, with the UK and Australia providing good templates. However, the requirement for adaptation to climate change as a current reality is a more recent issue with less clear guidance, especially for mainstreaming of the issue. 

World Wide

A World Bank View (Burton and Aalst, 1999)1:

A highly vulnerable system would be one that is highly sensitive to modest changes in climate, and one for which the ability to adapt is severely constrained. Projects include those where direct impacts of climate change may affect the viability of the project itself, or projects where consideration of climate change should be incorporated to avoid risks. Examples of vulnerable projects include coastal infrastructure, large hydro plants, or agriculture vulnerable to drought. Projects where risk could be reduced include agricultural research designed to increase output or irrigation projects – these projects may not be vulnerable themselves, but can be used to reduce vulnerability of the sector. Education and health projects were excluded, because such a broad definition would include almost all projects.

Climate change issues identified: 

  • low lying coastal lands periodically inundated by sea water driven inland by cyclonic storms (Bangledesh, Papua New Guinea)
  • small size and limited portfolio (Samoa)
  • floods and flash floods (Guyana, Papua New Guinea, Zimbabwe)
  • drought (Bangledesh, Papua New Guinea, Zimbabwe)
  • El Niño (Ecuador, Guyana)
  • rigid sea defenses (Guyana)

In some cases, climate change is being incorporated in projects, and in other, specific climate change studies have been implemented. However, few sectors and few countries have the capacity to deal with the anticipated extremes in climate.

A follow-up climate change assessment was prepared by Burton and Aalst in 20042, which emphasize the need for risk management in development practices. A scan of Country Assistance Strategies and project documents reaffirmed their earlier conclusions and suggested that climate risks had yet received due attention. They concluded a coherent system is needed that will consider together both current risks from climate variability and extremes as well as longer-term climate change. They also noted a growing interest in the potential of public involvement and public-private partnerships in insurance.

Climate change can be related to sustainable development and thus linked to the Equator Principles. These Principles, recently adopted by many International Finance Institutions (IFIs), provide an example of a comprehensive approach to IA for development projects. They require:

  • assessment of baseline environmental and social conditions,
  • requirements under host country laws and regulations,
  • applicable international treaties and agreements,
  • sustainable development and use of renewable natural resources,
  • protection of human health, cultural properties, and biodiversity, including endangered species and sensitive ecosystems,
  • consideration of use of dangerous substances, major hazards, occupational health and safety, fire prevention and life safety,
  • assessment of socio-economic impacts, land acquisition and land use, involuntary resettlement, impacts on indigenous peoples and communities,
  • assessment of cumulative impacts of existing projects, the proposed project, and anticipated future projects,
  • participation of affected parties in the design, review and implementation of the project,
  • consideration of feasible environmentally and socially preferable alternatives, efficient production, delivery and use of energy, pollution prevention and waste minimization, pollution controls (liquid effluents and air emissions) and solid and chemical waste management.

They do not, however, specifically mention climate change. Lawrence (2009)3 provides a recent review of the Equator Principles and their application in EIA and sustainability.

In March 27, 2008 the World Bank produced a Concept and Issues Paper for broad consultation entitled "Towards a Strategic Framework on Climate Change and Development for The World Bank Group". In this paper, Pillar 1 was identified as Scaling Up Operational Approaches to Integrating Adaptation and Mitigation in Development Strategies. This 46-page document describes risk and impacts generally but references the impact assessment process only in passing. 

The current focus of adaptation in assessing impacts of the environment on the project is of direct relevance to funding agencies, such as IFIs, and is gradually becoming integrated with the EIA process. This approach has developed from experience with projects particularly vulnerable to climate change, especially large water projects where precipitation is anticipated to change and coastal project potentially affected by sea level rise and increased storm magnitude or frequency.


1Burton, I. and M.K. van Aalst. 1999. Come Hell or High Water: Integrating climate Change Vulnerability and Adaptation into Bank Work. World Bank Environment Department Paper No. 72. The World Bank, Washington DC.

2Burton, I. and M.K. van Aalst. 2004. Look Before You Leap: A Risk Management Approach for Incorporating climate Change Adaptation in World Bank Operations. Prepared for the Global Climate Change Team (ENV), The World Bank, Washington DC. 

3Lawrence, P. 2009. Equator Principles: or How I Learned to Stop Worrying and Love Sustainability. Impact Assessment and Project Appraisal 27(1): 3-6.


The Arctic is a barometer of climate change, as indicated by the 2004 Arctic Climate Impact Assessment1 and more recent studies and assessments. Koivurova (2008) describes the complex issues surrounding EIA and transboundary assessments in the Arctic, including climate change2.

In Canada's North, an area experiencing some of the most intense changes in climate, EIA terms of reference have to date exclusively focused on how climate change may affect the viability of a proposed project. For example, the Gahcho Kué Environmental Impact Review Panel, a panel responsible for reviewing a proposed De Beers diamond Mine in Canada's Northwest Territories, summarized a common Canadian position in the 2007 terms of reference for its review3. It stated "(T)he scientific consensus is that the North is particularly vulnerable to impacts from a changing climate. The EIS must examine and evaluate the development as a potential greenhouse gas contributor. It must also examine potential climate change effects on the proposed development".

More recently, in a November, 2009 terms of reference for an EIA of a cobalt, gold, bismuth and copper mine4, the Mackenzie Valley Environmental Impact Review Board required the developer to describe annual carbon emisions over the life of the mine and describe any offsets proposed to mitigate carbon emissions. The Review Board also required descriptions of potential effects of climate change on the development: It required the developer to describe how geotechincal stability of all engineered structures at the mine will be ensured against a range of climate scenarios, and how climate change was considered in the development of the mine's closure and reclamation plan to ensure the long-term physical integrity of permanent structures.


1Arctic Climate Impact Assessment (ACIA). 2004. Arctic climate Impact Assessment: Impacts of a Warming Arctic. Cambrdige University Press. Available at .

2Koivurova, T. 2008. Transboundary Environmental Assessment in the Arctic. Impact Assessment and Project Appraisal 26(4): 265-275.

3 Gahcho Kué Environmental Impact Review Panel. October 5, 2007. Terms of Reference for the Gahcho Kué Environmental Impact Statement. Mackenzie Valley Environmental Impact Review Board, Yellowknife, NT, Canada

4 Mackenzie Valley Environmental Impact Review Board. November 30, 2009. Terms of Reference for the Environmental Assessment of Fortune Minerals Ltd. NICO Cobalt-Gold-Bismuth-Copper Project (EA 0809-004). Mackenzie Valley Environmental Imapact Review Board, Yellowknife, NT, Canada.


IAIA organized a conference focused on Cumulative Impact Assessment in Calgary, AB, Canada in November of 2008. The focus themes for this conference were: uncertainty (from a scientific perspective); institutional integration; and practice versus theory. Two major statements were made by conference organizers: 1) climate change is a Tragedy of the Commons where a common resource is threatened making it difficult to manage costs and benefits between stakeholders; 2) climate change is the BIG cumulative impact of our time. A single session focused on climate change with only two presentations made. One focused on the impact of GHG emission reductions from increasing the fuel efficiency of the US vehicle fleet, the other suggested that EIA focus initial efforts in broading the incorporation of climate change in the cumulative impact assessment component of EIA. Suggestions were made but prototype applications are needed, and not all jurisdictions even currently support cumulative impact assessment within their EIA process.


IAIA in conjunction with the World Bank, hosted a 2-day Symposium on November 2010 in Washington, DC, on the topic of Climate Change and Impact Assessment. 

See the background material including MDBs/IFIs' procedures/strategies, country procedures, good case studies, tools & resources and the background document providing the current “state of practice” details underlying the Symposium’s main discussion points.

Outstanding Issues

IA is based on establishing a baseline environmental and socio-cultural setting and superimposing the project or programme/policy scenario upon it. IA has not traditionally grappled with the prediction of future changes to the baseline setting, but in some cases major changes in the recent past are included in the description of the setting. Analysis is normally carried out in the assessment of impacts, but incorporation of climate change will require radical change when describing the background setting. Time scales become a more important component to be considered when assessments may precede construction or operational phases by many years. 

In addition to describing changes in climate over the anticipated life of the project or programme/policy, the environmental setting will need to include issues such as:

  • changes in migration patterns
  • changes in biodiversity and distribution ranges of relevant species
  • potential changes in harvesting of the affected resources

Biological studies and ecological modeling related to climate change are beginning globally, but considerable work remains to be done. In some cases the potential effects from climate change may be large enough to drastically change conclusions of the IA but further study is still needed to determine what types of systems and projects are the most vulnerable. One of the strong points of the IA process is the consistent manner used to assess the significance of impacts. The assessment of magnitude, duration and likelihood are largely unchanged by incorporating climate change into the process. 

Assessment of cumulative impacts are likely to be strongly influenced over time by consideration of climate change. Not all jurisdictions incorporate the assessment of cumulative impacts and in any cases this consideration is limited to the effect of other projects which might have overlapping impacts. As a starting point, incorporation of climate change effects on issues beyond GHG emissions and effect on the project is likely most practically addressed within the context of cumulative impacts. 

Further Reading

The Stern Review on the Economics of Climate Change, the most comprehensive review ever carried out on the economics of climate change, was published on October 30 2006 and was lead by Lord Stern, the then Head of the Government Economic Service and former World Bank Chief Economist. The UK Office of Climate Change is a good starting point for further reading.

The UK Climate Impacts Programme (UKCIP) has been helping organizations to adapt to inevitable climate change since 1997. A number of reports and tools are available through

Australia established the Department of Climate Change on 3 December 2007 as part of the Prime Minister and Cabinet Portfolio. The Department's web site has a wide range of reports and tools to help assess aspects of climate change mitigation and adaptation.


Background Document for the November 2010 IAIA Climate Change and Impact Assessment Symposium. The purpose of this report is to provide the current “state of practice” details underlying the Symposium’s main discussion points. Firstly, it provides a detailed overview of how the Multilateral Development Banks (MDBs) and International Financial Institutions (IFIs) are incorporating climate change risks and impacts into their corporate strategies and their due diligence procedures, particularly Environmental Impact Assessment (EIA). Secondly, it provides a detailed overview of how countries are adjusting their due diligence procedures to integrate climate change risks and impacts. Lastly, it attempts to draw lessons learned and best practices to assess the impacts of the climate change on the project and the impacts of the project on climate change.

Other Publications

NCEA's recommendations on Climate Change in EA The climate in the Netherlands is changing – that much is clear – but there is still uncertainty about the speed and extent of the change, and about the magnitude of the impacts: hence the need to test the climate resilience of spatial planning and spatial strategies. The environmental assessment (EA) procedure is potentially very useful in such testing, as it can be used to ascertain the contribution of plans and projects to abating greenhouse gas emissions and the feasibility of responding to the impacts of climate change. This article describes how the NCEA currently recommends dealing with the theme of climate change.

See Also

This page contains useful documents and websites including:

  • MDBs/IFIs' Procedures/Strategies
  • Country Procedures
  • Good Case Studies
  • Tools & Resources


Special thanks to Norval Collins for providing initial content for this IAIA Wiki topic.

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