Climate change and overheating: A multi-level risk assessment of impacts on Greek cities

Climate change and overheating pose significant risks and challenges for humans, for the
environment, and for contemporary cities. Among its consequences, urban overheating,
extreme weather events and heatwaves very often affect human life at various levels,
developing several societal, economic, and natural hazards. The Mediterranean region is one of
the most exposed to climate change risks areas in the world, due to its specific climate and
geographic characteristics in combination with the existing socio-economic gaps, population
growth and migration levels. Countries and cities located around the Mediterranean area
suffered from increased temperatures and heatwaves several times in recent years. Indicatively,
Cooling Degree Days -an indicator expressing the demand for space cooling due to increased
weather temperatures- have increased by around 57% since 1979 in Greece, according to
official statistics. Following the need to address these challenges, this study aims to identify and
evaluate the impacts and risks of overheating in the context of climate change in Greek cities. It
uses the method of Operational Risk Management in three steps. Firstly, it investigates the
hazards and risks of climate change through extended research in the recent literature,
classifying them to risks for humans (health, employment), environment (disaster of
ecosystems) and cities (building environment, economy, society). Secondly, the assessment of
the identified hazards is implemented through the evaluation done by different city stakeholders
involved in urban activities (public entities, research and academy, private sector, non-
governmental organizations, citizens). The results from the stakeholders are used at a later
stage for calculations, leading to a ranking of the hazards by importance/severity and by
probability of happening soon. The findings could shed light on the most vulnerable aspects of
the cities affected by climate change. This evaluation and the resulted ranking could be also an
important finding for policymakers to design and implement Disaster Risk Reduction (DRR) and
climate adaptation policies.
Keywords: climate change; heatwaves; Operational Risk Management; hazards severity