Evaluating spatiotemporal changes of heat risk in urban areas under climate change: the case study of Dublin, Ireland

Ireland and its cities are vulnerable to climate change. Ensuring resilience through adaptation strategies is now essential. Heat is considered a moderate but real risk in Ireland and Dublin is on the list of capital cities that are likely to experience one or more hazards in the RCP8.5 scenario, included heat-waves. In this work, we assess spatiotemporal variations of risk factors for (extreme) heat stress in Dublin city across different total radiative forcing scenarios i.e., RCPs, and periods (2020s - 2050s). Spatiotemporal projections of land cover have been combined with a Urban Energy Budget (UEB) model to derive an improved hazard indicator of heat stress i.e. the Universal Thermal Climate Index (UTCI) which accounts for Urban Heat Island (UHI) effect. This is combined with vulnerability assessment to map heat risk over time and space for different scenarios. Land-cover projections show that the level of exposure to extreme heat stress will increase in the coming decades. This will be particularly relevant for those areas designated for future high-density development where a reduction in green areas available is expected, with possible health and well-being implications for the population. Significant spatial clusters of areas affected by high heat risk are seen in the denser urban core of the city and north-western surroundings, highlighting that mainly disadvantaged people living there can be considered to be particularly vulnerable to the effects of overheating. This study provides a range of tools to support decision-making and planning for climate change adaptation at local and regional level in Ireland.