The extreme heat wave of July–August 2021 in the Athens urban area (Greece): Atmospheric and human-biometeorological analysis exploiting ultra-high resolution numerical modeling and the local climate zone framework

The extreme heat wave of late July/early August 2021 in Greece under the context of the direct effect of anthropogenic greenhouse gases

“…This is important in the framework of the associated impacts on human health mentioned above. Under the same context, a future study could also focus on the effects of anthropogenic greenhouse gases on the night‐time temperatures, which are known to have a more damaging impact on the human body (Giannaros et al, 2023).…”

“…Near-surface air temperature observations, derived from the NOA/Meteo network of ground-based weather stations (Kotroni et al, 2021;Lagouvardos et al, 2017), and the ERA5 model reanalysis data (Hersbach et al, 2020) are used to (i) climatologically characterize the JA2021HW and (ii) validate the NOA/Meteo operational WRF model (version 4.4;Skamarock et al, 2019) in terms of reproducing the August 3, 2021, Tmax in the study area (Greece; Figure 1a). The configuration of the WRF model includes a high-resolution simulation domain (2 Â 2 km) over Greece and neighboring countries (Giannaros et al, 2023).…”

“…Up to 11-year records of daily maximum temperatures (Tmax) were exceeded in more than 10 stations of the nationwide observational network operated by the Meteo Unit at the National Observatory of Athens (NOA; Lagouvardos et al, 2017) and 265 of them recorded temperatures higher than 40 C on August 3rd, 2021. The second-highest Tmax since 1900 was also recorded in the historical climatic station of NOA in Athens on the same day (Giannaros et al, 2023). In terms of heat-related parameters that affect the human thermal environment, JA2021HW ranks first among episodes identified since 1900, with respect to the highest nighttime temperature and greater accumulated heat and thermal discomfort (Founda et al, 2022).…”

“…Unfortunately, this was the case during the late July/early August 2021 HW (JA2021HW) that affected Greece. The episode, defined based on a percentile‐based approach (Giannaros et al, 2023), lasted for 9 days (July 28–August 5, 2021) and was characterized as extreme in terms of intensity and duration (Founda et al, 2022; Giannaros et al, 2023). Up to 11‐year records of daily maximum temperatures (Tmax) were exceeded in more than 10 stations of the nationwide observational network operated by the Meteo Unit at the National Observatory of Athens (NOA; Lagouvardos et al, 2017) and 265 of them recorded temperatures higher than 40°C on August 3rd, 2021.…”

Hourly values of an advanced human-biometeorological index for diverse populations from 1991 to 2020 in Greece

“…It also allows for clothing and activity modifications 12 , 18 , which are necessary when considering the sensitivities of diverse populations to thermal stress. Thus, mPET constitutes a universally applicable human-biometeorological index under different climatic contexts and various research and operational activities 49 , 69 – 71 .…”