Optimalisasi Kebijakan Tata Ruang Terbuka Hijau sebagai Strategi Mitigasi Urban Heat Island (UHI) di Kota Surabaya

Optimizing Green Open Space Policy as an Urban Heat Island (UHI) Mitigation Strategy in Surabaya City The city of Surabaya faced an extreme surface temperature anomaly reaching nearly thirty-six degrees Celsius in April two thousand twenty-six, which exacerbated the urban heat island phenomenon. A paradox occurred because the city government had previously claimed the fulfillment of the public green open space target of twenty-two percent. This study evaluated the effectiveness of the green open space spatial policy in Surabaya and formulated an adaptive policy reorientation strategy. A qualitative research approach was utilized through a non-participatory field observation method to directly assess the physical quality of the green open space canopy and built-up areas. These field data were then triangulated with formal spatial planning documents and spatial secondary data from surface temperature satellite imagery within a policy gap analysis framework. The results indicated a failure in the ecological function of the green open spaces in the field. This implementation gap was driven by a policy orientation that focused on land extensification and visual aesthetics without prioritizing the quality of broad-canopy vegetation, as well as spatial distribution disparity due to the massive shrinkage of green spaces in densely built areas. To address the limitation of horizontal land, this research recommended a policy reorientation that mandated the provision of vertical gardens and roof gardens through the integration of building approval requirements for developers, accompanied by an incentive scheme of land and building tax reduction to encourage collaborative governance with the private sector.