Katerina Pantavou

Heat waves observed in 2007 in Athens, Greece: Synoptic conditions, bioclimatological assessment, air quality levels and health effects ☆

Heat waves are considered to be increasing in frequency and intensity whereas they comprise a significant weather-related cause of deaths in several countries. Two heat waves occurred in Greece in summer 2007. These severe heat waves are assessed by analyzing the prevailing synoptic conditions, evaluating human thermal discomfort, through the Heat Load Index (HL), as well as investigating its interrelation of air pollutant concentrations, and the daily air quality stress index (AQSI), in the greater region of Athens (Attica), Greece. Furthermore, the relation of HL values and the number of heatstroke and heat exhaustion events recorded in public hospitals operating within the Greek National Health System is examined. Data included radiosonde measurements from the Athens airport station (LGAT), NCEP/NCAR reanalysis data in order to obtain the position of the Subtropical Jet Stream (STJ), GDAS meteorological data for back-trajectory calculation, 10-min meteorological data from 10 Hydro-Meteorological stations and mean hourly values of nitric dioxide (NO(2)), sulphur dioxide (SO(2)) and ozone (O(3)) concentrations, measured at 7 different sites, for the last 10-day period of June and July 2007. Spearmans rank correlation test was used to observe any possible correlation between HL values and air pollutant concentrations, and AQSI values. The results demonstrated different synoptic characteristics for the heat waves of June and July. In the heat wave of June, higher ambient temperatures were recorded and greater HL values were calculated. Extreme discomfort conditions were identified in both heat waves during both day-time and night-time hours. The air pollution analysis showed poor air quality conditions for the heat wave of July, while a significant correlation was found between HL values and average hourly concentrations of O(3), NO(2) and SO(2). The number of heat-affected patients reported during the June heat wave was larger.

Biometeorological and air quality assessment in an industrialized area of eastern Mediterranean: the Thriassion Plain, Greece

Evidence that heat wave events are associated with poor air quality conditions and health hazards has become stronger in recent years. In this study, the impact of two heat wave episodes on human thermal discomfort and air quality is examined during summer 2007, in an industrial plain of eastern Mediterranean: the Thriassion Plain, Greece. For this purpose, two biometeorological indices—Discomfort Index (DI) and Heat Load (HL)—as well as an air quality index—Air Quality Stress Index (AQSI)—were calculated using data from seven measuring sites. A land-use map was procured in order to examine the effect of different land cover types on human thermal comfort. The results indicated high level of thermal discomfort and increased air pollution levels, while a significant correlation between the DI and the AQSI was identified.

Evaluation of thermal discomfort in Athens territory and its effect on the daily number of recorded patients at hospitals’ emergency rooms

Previous research has shown that temperature and humidity affect human health. However, only a few studies have examined the association of a biometeorological index, which combines several meteorological parameters and human physiology, with health outcomes. The aim of the present study is to assess the thermal discomfort in Athens city by using the Predicted Mean Vote (PMV) as well as to examine its association with the number of patients recorded at the emergency rooms of four main hospitals. Patients were selected based on their diagnosis during the summer season (June–August) from 1998 to 2004. Data included hourly values of meteorological parameters and daily numbers of patients who visited the emergency units of cardiology departments. Poisson regression models were applied using generalized estimating equations. A strong negative correlation between mean and maximum daily values of PMV and the number of emergency department visits was identified. More studies are needed to explore the association of this biometeorological index with health outcomes in other regions.

Evaluating the performance of bioclimatic indices on quantifying thermal sensation for pedestrians

Previous studies have shown that bioclimatic indices predictions differ from actual thermal sensation and that their predictability varies depending on the climate. This study aims to assess the potential of a large number of widely used bioclimatic indices to describe human thermal sensation as well as to identify the one that most successfully simulates thermal sensation in a Mediterranean urban environment. Field questionnaire surveys were conducted along with weather measurements at three sites with different microclimatic characteristics in Athens, Greece. The predicted by the indices thermal sensation was compared to the actual thermal sensation that was indicated on a seven-point thermal sensation scale by the respondents, named as thermal sensation vote. Three statistical and one qualitative criterion were applied. Analysis showed a significant correlation between predicted and actual thermal sensation, indicating a strong correlation when indices classes were taken into account. The majority of indices predicted successfully about 35% of thermal sensation votes, while the maximum percentage of successful predictions was estimated to be 57.9%. The four criteria used were sufficient to evaluate indices performance. Subjective Temperature Index and Universal Thermal Climate Index showed the best applicability compared to all the indices studied.

Modeling thermal sensation in a Mediterranean climate—a comparison of linear and ordinal models

A simple thermo-physiological model of outdoor thermal sensation adjusted with psychological factors is developed aiming to predict thermal sensation in Mediterranean climates. Microclimatic measurements simultaneously with interviews on personal and psychological conditions were carried out in a square, a street canyon and a coastal location of the greater urban area of Athens, Greece. Multiple linear and ordinal regression were applied in order to estimate thermal sensation making allowance for all the recorded parameters or specific, empirically selected, subsets producing so-called extensive and empirical models, respectively. Meteorological, thermo-physiological and overall models - considering psychological factors as well - were developed. Predictions were improved when personal and psychological factors were taken into account as compared to meteorological models. The model based on ordinal regression reproduced extreme values of thermal sensation vote more adequately than the linear regression one, while the empirical model produced satisfactory results in relation to the extensive model. The effects of adaptation and expectation on thermal sensation vote were introduced in the models by means of the exposure time, season and preference related to air temperature and irradiation. The assessment of thermal sensation could be a useful criterion in decision making regarding public health, outdoor spaces planning and tourism.

Data on solar sunburning ultraviolet (UVB) radiation at an urban Mediterranean climate

This article describes data on the intensity of ultraviolet B (UVB) radiation collected during field questionnaire-based surveys in Athens, Greece. The surveys were conducted over 11 days of July and October 2010 at three different urban, outdoor sites. A total of 1104 interviews were conducted. The participants were asked to report whether they felt they got a sunburn at the moment of the interview. Questions related to personal characteristics including skin type and exposure time (visit duration at the interview site) were also included in the questionnaire.

Molecular investigation of HIV-1 cross-group transmissions during an outbreak among people who inject drugs (2011–2014) in Athens, Greece

New diagnoses of HIV-1 infection among people who inject drugs (PWID) rocketed in Athens, Greece between 2011 and 2014 (HIV-1 outbreak). Our aim was to identify, during that period, potential cross-group transmissions between the within-Greece PWID and other risk or national groups using molecular methods. Sequences from 33 PWID were outside the PWID-outbreak networks in Greece (PWID-imported transmissions). Phylogenetic analyses on 28 of these sequences (subtypes A and B) showed that 11 subtype B infections originated from Greece, whereas 8 and 7 subtype A strains were from former Soviet Union countries (AFSU) and Greece, respectively. The putative source in half of the PWID-imported transmissions with Greek origin was an individual who acquired HIV via sexual contact. During four years of an HIV-1 outbreak among PWID in Athens, Greece, 33 individuals in this group (4.6% of all diagnoses with phylogenetic analyses) are likely to represent infections, sexually or injection-acquired, outside the within-Greece-PWID-outbreak networks. Combined molecular and traditional HIV surveillance to monitor introductions of new strains, and interventions that aim at reducing the rate of both injection and sexual risky practices are needed during drug injection-related HIV outbreaks.

Comparison of Actual Thermal Vote with Two Objective Human-Biometeorological Indices Values

In July 2010, a field study on the biometeorological conditions and human thermal comfort was carried out in Athens. The experiment was conducted during six different days in three different sites, Syntagma Square, Ermou Street and Flisvos coast. The collected data included measurements of meteorological parameters and subjective assessments of thermal sensation from morning to evening for each site. A mobile meteorological station collected data of air temperature, relative humidity, wind speed, total solar radiation, surface ground temperature and globe temperature while a group of five healthy and acclimatized subjects exposed to the environmental conditions completed every 30 min a questionnaire about their thermal sensation at the moment of measurement. Two biometeorological indices, Thermal Sensation (TS) and Heat Load (HL), were calculated in order to compare the indices values with the actual thermal vote of the five subjects. The analysis showed that TS underestimates the thermal sensation of the five subjects when their thermal vote is ‘hot’ or ‘very hot’ while TS overestimates the thermal sensation of the subjects when their thermal vote is ‘neutral’. The HL index overestimates the thermal sensation of the subjects.