Supplementary material for Rojas et al. 2020 Eduardo Fernandez a* , Gonzalo Rojas b , Cory Whitney a , Italo F. Cuneo b , and Eike Luedeling a a Department of Horticultural Sciences, Institute of Crop Science and Resource Conservation (INRES), Auf dem Hügel 6, D-53121 Bonn, Germany b Escuela de Agronomía, Pontificia Universidad Católica de Valparaíso, Casilla 4-D, Quillota, Chile The following document is a supplement to the work “Adapting sweet cherry orchards to hazardous weather events — Decision Analysis in support of farmers’ investments in central Chile” by Gonzalo Rojas, Eduardo Fernandez, Cory Whitney, Eike Luedeling and Italo F. Cuneo, published in the journal Agricultural Systems. Introduction Farming systems are among the most vulnerable schemes regarding the impacts of climate change. Growers in subtropical regions may expect an increase in the frequency and magnitude of what are currently considered unusual weather events. To deal with this situation, and remain productive under future scenarios, growers must adapt their orchards by implementing technologies that mitigate the impacts of climate change on agricultural systems. However, available options for mitigating these impacts involve a number of risks and uncertainties, leaving growers hesitant about the benefits of implementing new technologies to protect their orchards. Here we use a case study in northern- and southern-central Chile to demonstrate the applicability of Decision Analysis approaches to embrace the inherent uncertainty when making decisions. We applied a participatory modeling approach to collect and analyze qualitative and quantitative knowledge regarding the decision to apply polyethylene covers in sweet cherry orchards. We gathered relevant experts and key stakeholders to identify important variables and develop a causal impact pathway model for the adoption decision. We implemented the model as a Monte Carlo simulation and projected probability distributions for the Net Present Value (NPV) and the annual cash flow. Additionally, we determined the most relevant variables affecting the decision via Partial Least Squares regression and Expected Value of Perfect Information analysis. We provide information on the focus group meeting procedure as well as a working example to demonstrate the applicability of the decisionSupport package (Luedeling et al., 2020) for comparing two investment options through decision analysis approaches. This working example is focused on the process we adopted after obtaining the conceptual pathway of the decision in the workshop with stakeholders. For more on the preliminary processes see the main manuscript. Focus group meeting procedure As mentioned in the main manuscript, the focus group meetings aimed to identify the growers’ major concerns regarding the impacts of climate change on the cultivation of sweet cherry trees in central Chile. The procedure consisted of statements and conversations that were guided by the meeting moderator. Major concerns were identified through a qualitative approach based on agreement among the participants. In this approach, farmers generated a prioritized list of potential risks under a changing climate. These prioritized lists (i.e. one for each of the zones) helped us frame our work. Since this manuscript is part of a bigger project, for a detailed document on the complete procedure, please contact the corresponding author. * Eduardo Fernández (efernand@uni-bonn.de) 1