NOCTURNAL URBAN HEAT ISLAND (NUHI) MITIGATION IN HIGH-DENSITY AREAS IN THE NETHERLANDS

Abstract

This thesis explores whether and how Nocturnal Urban Heat Island (NUHI) mitigation is considered and integrated into the decision-making in the urban planning process of two highpopulation densification areas: Beurskwartier 1 in Utrecht and Sloterdijk Stationskwartier in Amsterdam, the Netherlands. This study aims to enhance the mitigation of nighttime heat in high-population densification developments within a warming climate.

The research is based on interviews with experts in UHI mitigation and urban planning, a thorough analysis of environmental policy documents from Utrecht and Amsterdam, and interviews with a diverse range of actors involved in the urban planning processes of the two case studies.

The results indicate that Nighttime heat mitigation is not considered but indirect NUHI mitigation measures are applied. Urban greening was the only found strategy entailing both area-based and point-based mitigation measures. Zoning-based strategies are lacking, and area-based measures are not used to the full extent. To enhance NUHI mitigation in the urban planning process actors called for a clear overview of effective strategies, a strong policy foundation, and the inclusion of effective strategies and measures in the early phases of the planning process.

Based on the outcomes, practical recommendations are provided how to practically integrate NUHI mitigation measures acknowledging experienced barriers, temporal dynamics and crucial documents attached, the different interests, and the legal framework.

Overall, this thesis offers valuable insights into how NUHI mitigation can be applied and improved in urban planning processes of high population density developments. This study contributes to making high-density urban areas more resilient to nocturnal heat impacts and can be used as starting point for future research into urban climate and heat mitigation integration in the decision-making process of urban planning.