Impact of climate variability at local, regional, and global scales on chili productivity in Sleman Regency, Indonesia

¹ Doctor Programme of Agricultural Engineering Science, Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, 55281 Indonesia
² Indonesia Agency for Meteorology Climatology and Geophysics (BMKG), Climatology Station of Yogyakarta, Yogyakarta, 55284, Indonesia
³ Department of Agricultural and Biosystems Engineering, Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia
⁴ Center of Land Resources Management, Universitas Gadjah Mada, Yogyakarta, 55281, Indonesia
⁵ Center for Climate Change, Indonesia Agency for Meteorology Climatology and Geophysics (BMKG), Jakarta, 10610, Indonesia

Abstract

As a strategic commodity for inflation stabilization, red chili relies heavily on Sleman Regency, a vital agricultural area. Nevertheless, climate variability poses significant threats, with irregular rainfall and temperature fluctuations driving water scarcity, flooding, and pest and disease outbreaks. This study analyzes climate variability impacts on chili productivity using 2014–2023 yield and rainfall data from 17 districts in Sleman across local to global scales. Key climatic drivers rainfall, Sea Surface Temperature (SST), El Niño–Southern Oscillation (ENSO), and Indian Ocean Dipole (IOD) were assessed using multiple linear regression and Spearman correlation. To detect anomalies, a Monte Carlo Bootstrap with 1000 resamplings was applied during ENSO years across four climatological seasons (DJF, MAM, JJA, SON). Rainfall was the dominant factor in most districts, while SST showed regional influence. Although ENSO and IOD were not statistically significant in regressions, ENSO events triggered marked spatial and seasonal anomalies. El Niño reduced yields by about 40% during JJA and MAM, while La Niña caused greater declines, exceeding 40%, especially in MAM and JJA. These findings highlight the urgency of climate-informed planning through adjusted planting calendars, irrigation development, and resilient varieties to sustain chili production under rising climate pressure.