Projected changes in climate suitability for the Brown Planthopper (

One of the impacts of climate change in the agricultural sector in Indonesia is the shift in the distribution of the brown planthopper (Nilaparvata lugens), a significant threat to rice cultivation in Indonesia. This study provides one of the first CLIMEX-based assessments of brown planthopper climatic suitability in West Java using multi-model CMIP6 projections and spatial autocorrelation analysis. Baseline (1990-2020) and future climate conditions (2040-2060) were simulated under the SSP2-4.5 and SSP5-8.5 scenarios using four CMIP6 models (ACCESS-CM2, EC-Earth3-Veg, GISS-E2-1-G, and HadGEM3-GC31-LL). Climatic suitability was quantified using the Ecoclimatic Index (EI), while spatial clustering was evaluated using Moran's statistics. Under baseline conditions, high-suitability zones (EI 51-75) are predominantly concentrated along the northern coastal regions, especially in Indramayu, Karawang, and Subang. Under future scenarios, suitable areas expand southward and into middle-altitude regions, increasing from approximately 40% at present to nearly 80% under SSP5-8.5. Spatial analysis indicates significant clustering of suitability across neighboring districts. These findings indicate that rising temperatures increasingly support brown planthopper development, thereby elevating pest risk in major rice-producing areas of West Java.