Climate change over Indonesia and its impact on nutmeg production: An analysis under high-resolution CORDEX-CORE regional simulation framework

Abstract

Nutmeg is an important spice and contributes significantly to the gross domestic product of Indonesia. The study examines the impact of climate change on Indonesia and the production of nutmeg over Banda Neira Island. For this, the outputs from high-resolution regional climate models under different representative concentration pathways (RCP2.6, RCP4.5 and RCP8.5), within the framework of Coupled Model Intercomparison Project 5/Coordinated Regional Climate Down-scaling Experiment-Coordinated Output for Regional Evaluations (CMIP5/CORDEX-CORE) over southeast Asia domain are employed. The representation of the spatial structure of rainfall and temperature climatology is found to be much better in ensembles as compared to individual model experiments. The behaviour of simulated rainfall and temperature from the model experiments is examined to check whether the projected climate favours an increase in nutmeg production. The study found that projected changes in the number of wet days (ideal 100–160 wet days), heavy rainfall events, rising mean temperature above the optimum temperature range (25–26°C), increasing heatwave spells, and prolongation of the warm period led to an unfavourable climate for nutmeg production. Based on the analysis of dynamically produced (model simulated) climate variables, the study rejects the forecasted increase in nutmeg production using a statistical regression model due to the unfavourable climatic conditions that are likely to affect the growth, production and quality of nutmeg. The changing climate not only reduces regional agricultural production but also impacts the socio-economic condition of the people of Indonesia. Therefore, the study emphasizes implementing stringent climate laws and policies at global, regional and local levels to curb greenhouse gas emissions and reduce the negative impact of climate change.