Analysis Daily Maximum Temperature Prediction in East Java Under the RCP 8.5 Scenario

Abstract

East Java, a province of critical economic and agricultural importance in Indonesia, faces escalating risks from climate change. This study provides high-resolution projections of daily maximum temperatures for the period 2025–2050 to establish an evidence-based foundation for regional adaptation strategies. Using a Support Vector Regression (SVR) model, this study projects future temperature dynamics under the high-emission Representative Concentration Pathway 8.5 (RCP 8.5) scenario. The results reveal a statistically significant long-term warming trend of +0.03℃ per year. Spatially, the model identifies two distinct risk patterns: (1) persistent absolute heat "hotspots" in northwestern urban lowlands (>32℃), driven by the Urban Heat Island (UHI) effect; and (2) the most rapid warming anomalies (up to +0.45℃) in southern and coastal agricultural regions. A crucial finding is a projected seasonal shift where the wet season is expected to become systematically hotter than the dry season, introducing new humidity-compounded heat stress. These differentiated risks underscore the urgent need for targeted, data-driven policies in agriculture, public health, and urban planning to build climate resilience for East Java's high-emission future.