MORDIC · Mortality Risk Attributable to Thermal Discomfort Indicators with Implications of Climate Change

Mortality Risk Attributable to Thermal Discomfort Indicators with Implications of Climate Change

Environmental epidemiologists and physiologists continue to disagree on the importance of humidity when assessing heat-related impacts on human mortality. The former community has favoured ambient air temperature (Tair) as the preferred environmental exposure variable. Their argument is deep rooted in studies, wherein humidity when included in empirical models, did not substantially improve its predictive power compared to those using only Tair as a exposure variable. On the contrary, using laboratory-based settings, the latter community have demonstrated that humidity, in addition to Tair, often expressed as different standalone heat stress indices (HSIs), plays an important role to explain how human physiology regulates the core body temperature when exposed to elevated levels of heat stress. Nonetheless, scientific evidence has remained elusive with no single HSI considered as universally applicable in different climate regimes and population settings. The MSCA project MORDIC systematically examined whether: (i) commonly used HSIs (e.g., wet bulb temperature, heat index) perform better than Tair in explaining heat-related health impacts at city-level; (ii) the association of HSIs and mortality varies geographically, and if so, which factors are instrumental for this variance; and (iii) the subsequent excess-deaths attributable to non-optimal heat stress differ when estimated using HSIs instead of Tair. The above research objectives (ROs) and the subsequent findings published in numerous peer-reviewed studies, have enabled not only the scientific community, but also the public health authorities and decision makers to gain valuable insights in cross-disciplinary subjects. Whether or not the regional-scale health-impact assessments should utilise HSI (in lieu of Tair) is a direct outcome of the above ROs addressed by MORDIC. In addition, a parallel and important goal of the MSCA Fellowship was to foster the development of the individual researcher and contribute to the host institute’s outreach in epidemiological and public health research areas.

Data: CORDIS, © European Union