Conceptualising and Assessing Heatwave Impacts

This chapter discusses the multifaceted nature of heatwave impacts and proposes a methodology for their assessment. The chapter begins by defining heatwave impacts as the consequences of realised risks as influenced by the interaction of the heatwave hazard, heatwave related exposure and vulnerability and responses to heatwaves. A key focus is the differentiation between direct and indirect impacts, tangible and intangible impacts, and the propagation of these impacts through systems over time and space. The chapter underscores the need for systematic reporting and assessment of heatwave impacts to inform the development of effective risk management strategies and notes that without comprehensive heatwave impact data managing the risks associated with heatwaves will be more guesswork than evidence based. Because little is available in the literature regarding how to conduct a heatwave impact assessment, a five-step methodology for Heatwave Impact Assessment (HWIA) is introduced. This includes setting objectives and context, conceptualizing impacts, locating evidence of impacts, assessing impacts, and developing heatwave impact management strategies. This methodology is designed to provide a comprehensive framework for understanding and managing the consequences of heatwaves. In relation to the various HWIA steps, recommendations are made with regards to the type of data that can be harnessed for context setting and analysis of the heatwave hazard plus the use of various analytical techniques such as dependency and cross impact analysis matrices and event trees. A list of heatwave metrics is also suggested covering a range of sectors.