Gerald Nelson, University of Illinois at Urbana-Champaign (Professor Emeritus)
John Antle, Oregon State University
The Economics Team’s goal is to establish a methodological and procedural foundation for the systematic comparison and improvement of global and regional land use, production and trade models used for analysis of climate change impact, as well as mitigation and adaptation in the agricultural sector.
The main objectives of the team are to:
1) Improve documentation, standardization and transparency of economic data and models.
2) Develop “Representative Agricultural Pathways” or RAPs matching the concentration pathways and socio-economic pathways being developed by the global integrated assessment communities.
3) Advance the methods and procedures used to link crop and economic models for analysis of climate change impact, mitigation and adaptation in the agricultural sector.
4) Design and implement regional analysis of climate change impact and adaptation using new methods for crop and economic model linkages, and carry out intercomparisons for a set of designated test regions where high-resolution bio-physical and economic data are available, including the regions that are the focus of the regional workshops discussed below.
5) Facilitate inter-comparison of global agricultural market models using AgMIP crop model simulations.
Achieving these objectives will involve participating in the AgMIP cross-cutting themes to build collaborations between climate scientists, crop modelers and economic modeling groups to improve methods and procedures that allow crop model simulations to be used as inputs into economic models. First, an important part of AgMIP’s work will be to facilitate the transdisciplinary development of agricultural scenarios referred to as Representative Agricultural Pathways (RAPs). Second, methods are needed to allow site/point analysis to be scaled up to agroecological zones (AEZs) or larger regions, and to statistically characterize uncertain yield distributions and the effects of temperature thresholds and crop failure in economic models.
A third important issue that arises in using crop model simulations is how to interpret crop model yields, e.g., as absolute or relative productivities. (Initially, AgMIP crop modelers are proposing to aggregate from site to regional yields as well as scaling to the absolute regional yields accounting for “yield gap” relationships, but these issues will be further addressed as AgMIP proceeds). A fourth important set of issues concerns the characterization of management data. Various issues arise here, including spatial and temporal aggregation of inputs; representation of human labor; pest management; measurement of capital stocks or capital service flows; and dynamic feedbacks from economic decision models to crop models, within and across seasons.
Another major AgMIP initiative will involve coordinating and facilitating intercomparison of both regional and global agricultural market models being used for climate change impact and adaptation research. The AgMIP Leadership Team will work with major regional and global agricultural economic modeling teams to implement a suite of model runs utilizing the AgMIP crop model simulations and RAPs. Regional models will be intercompared for a selected set of regions where high-resolution biophysical and economic data are available. For these regions, it will be possible to compare alternative methods for coupling biophysical and economic models, and it will also be possible to then cross-validate global models with regional models in those regions.
For global economic model intercomparison, the goal will be to include models with global coverage and several other key features, including:
• significant disaggregation, to the country level at a minimum;
• explicit integration of biophysical modeling at a relatively high spatial resolution of crop response to management, choice of variety and weather;
• water supply and demand responses to weather and irrigation infrastructure investment;
• some mechanisms to model biotic stresses and yield-gaps;
• multiple policy levers for agricultural trade and investments of many kinds.
Highlights of the 2011-2012 AgMIP Economics Team can be downloaded as a pdf here.