Page 82 - Climate Change and Food Systems

climate change and food systems: global assessments and implications for food security and trade
1. Introduction
The literature on climate impacts and adaptation in agriculture is growing exponentially. At the same time the need for action on adaptation is urgently felt at local, national and global levels. Climate adaptation planning and interventions at all levels need to be based on the best available evidence to date despite gaps in current knowledge and the persistent uncertainty about the specific climate outcomes and their likelihoods. It is thus imperative to assemble, evaluate and make accessible the scientific and socio-economic advances in our understanding of climate impacts on agriculture and food security.
Climate change and its complex manifestations have brought together different knowledge disciplines from climate science, biophysical processes and socio-economic drivers all the
way to issues of geography and sociology.
Each of these disciplines contributes to our understanding of climate change effects; but
only when fully integrated do we form a more complete assessment that can translate into policy action. While climate science and related biophysical processes have received much attention and effort, the economics of climate adaptation remain understated. Yet the economic analysis of adaptation is an essential step toward forming informed policy action. This paper attempts to fill this gap by providing a broad and informative review of the economic modelling of climate impacts, demonstrating the importance of economics of adaptation within the broad climate impact analysis, and highlighting the strengths, weaknesses and gaps in current economic literature. This paper focuses on agriculture and several important drivers: food security, water and trade.
The chapter has three objectives: (i) to review and synthesize recent findings linking climate impacts to agriculture; (ii) to evaluate the economic literature contributions to evaluating adaptation options and decisions by relevant actors; and (iii) to identify gaps and formulate
suggestions for further research. We aim to offer both an informative and critical contribution to the relevant economic literature and in so doing attempt to reach beyond the circle of specialist economists. The models and analytical methods reviewed are examined through their strengths, weaknesses and their relevancy in providing policy-relevant insights.
We place particular emphasis on analyses focusing on climate impacts and highlight the
ways in which economic analyses describe climate change adaptations. Special attention is given to the economic models that are part of integrated assessments models which also link with global climate models and impact (or pathway) models. The latter generate biophysical and physical impacts, such as changes in crop yields or crop land inundation. For many economists, the climate and pathway models that provide the foundations of integrated economic climate assessments present new territory, and this introductory overview may be informative. We also review household-level models since much adaptation decision-making takes place at the local or farm level. Throughout the review we look at how
the economic models handle climate-related uncertainty.
Our criteria for selecting the analyses included in this survey follow from our objectives. They emphasize timeliness, methodological interest, and applied policy relevance. We selected studies in which all or most of these criteria were met:
(i) Analyses are based on standard global climate modelling projections from no earlier than
the 4th Intergovernmental Panel on Climate Change (IPCC) assessment.
(ii) Analyses inform adaptation decision-making processes and are policy relevant.
(iii) Analyses are illustrative and exemplary of current methodologies that analyse climate change impacts and adaptation related to agriculture and food security.
(iv) Analyses offer representative geographic diversity in their application, with emphasis on developing countries.
62