Towards the development of adaptation options using climate and crop yield forecasting at seasonal to multi-decadal timescales

In order for climate forecasting to be used in developing adaptation options, the forecasts should be able to affect decisions made by stakeholders in a manner that improves outcomes. The implications of this requirement for forecasting are presented under five headings: relevance, reliability, stakeholder engagement, holism and accuracy. These characteristics are elucidated through a particular focus on the use of ensemble climate and crop simulations. Resulting recommendations, including comments on mainstreaming and seamlessness, are described using the concepts of quality and value. Adaptation options can be developed using climate forecasts on a range of timescales, from days to decades. Using the five identified characteristics, two cases are presented: (i) options based on large-area seasonal crop yield forecasting are discussed, and (ii) genotypic adaptation based on long-term climate change projections is examined. For the latter, novel analyses of existing large-area groundnut simulations are used to assess the magnitude and spatial extent of the impact of changes in the mean and variability of temperature, rainfall and humidity. The genotypic properties required to ameliorate negative impacts are then assessed and compared to observations. The processes examined act on most annual crops, making the method, and to some extent the results, broadly relevant.