Probabilistic forecasting of remotely sensed cropland vegetation health and its relevance for food security

• Published in: The Science of the total environment Vol. 838; no. Pt 2; p. 156157
• Main Authors: Hammad, Ahmed T., Falchetta, Giacomo
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 10-09-2022
• Subjects: Food security; Probabilistic machine learning; Remote sensing of the environment; Vegetation health; Vulnerability analysis; Vegetation health; Vulnerability analysis; Remote sensing of the environment; Food security; Probabilistic machine learning
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2022.156157

In a world where climate change, population growth, and global diseases threaten economic access to food, policies and contingency plans can strongly benefit from reliable forecasts of agricultural vegetation health. To inform decisions, it is also crucial to quantify the forecasting uncertainty and prove its relevance for food security. Yet, in previous studies both these aspects have been largely overlooked. This paper develops a methodology to anticipate the agricultural Vegetation Health Index (VHI) while making the underlying prediction uncertainty explicit. To achieve this aim, a probabilistic machine learning framework modelling weather and climate determinants is introduced and implemented through Quantile Random Forests. In a second step, a statistical link between VHI forecasts and monthly food price variations is established. As a pilot implementation, the framework is applied to nine countries of South-East Asia (SEA) with consideration of national monthly rice prices. Model benchmarks show satisfactory accuracy metrics, suggesting that the probabilistic VHI predictions can provide decision-makers with reliable information about future cropland health and its impact on food price variation weeks or even months ahead, albeit with increasing uncertainty as the forecasting horizon grows. These results - ultimately allowing to anticipate the impact of weather shocks on household food expenditure - contribute to advancing the multidisciplinary literature linking vegetation health, probabilistic forecasting models, and food security policy.
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•Important to monitor weather, crop health and food security nexus•Probabilistic ML framework to anticipate cropland vegetation health•Most forecast reliable even months ahead, but increasing uncertainty•Probabilistic vegetation health forecasts statistically linked to food prices•Framework implemented in nine countries of South-East Asia