According to ELSTAT data, the majority of road accidents and fatalities occur during clear sky, both inside and outside built-up area. However, accident severity is increased during raining and other weather conditions.

Road Safety by Seasonability in the EU is highlighted at the Traffic Safety Basic Facts 2015 available at the European Road Safety Observatory of the European Commission. These Traffic Safety Basic Facts contain a comprehensive series of statistical tables with the latest available data from the CARE database of the European Commission. Although the annual number of people who died in road accidents in Europe has fallen over many years, the distribution of the annual number by month has scarcely changed, with the fewest fatalities recorded in February and the most in July/ August. However, the distribution of fatalities by month varies considerably from country to country, and it tends to vary most in Northern Europe and least in Western Europe. 

Athanasios Theofilatos has successfully defended his PhD thesis titled: An advanced multi-faceted statistical analysis of accident probability and severity exploiting high resolution traffic and weather data. This PhD thesis was carried out at the Department of Transportation Planning and Engineering at the School of Civil Engineering of the National Technical University of Athens under the supervision of Prof. George Yannis. The objective of this PhD thesis is the investigation of accident probability and severity exploiting high resolution traffic and weather data from urban roads and motorways, collected on a real-time basis, with specific focus on Powered-Two-Wheelers. For that purpose, an advanced mesoscopic multi-faceted statistical analysis was conducted in order to expand previous road safety work and contribute to the further understanding of the complexity of accident probability and severity. Linear and non-linear models were developed on the basis of 6-year accident data from urban roads as well as an urban motorway in Greater Athens area (Attica Tollway). Empirical findings indicate that high resolution traffic and weather data are capable of opening new dimensions in accident analysis in urban roads and urban motorways. The multi-faceted statistical analysis conducted in the thesis has revealed a consistent and strong impact of traffic parameters on accident probability and severity. It is interesting that weather parameters were not found to influence accident probability and severity when linear relationships are considered, however, the application of cusp catastrophe models demonstrated that it is likely that even small traffic and weather changes may have a critical impact on road safety in urban roads as sudden transitions from safe to unsafe conditions (and vice versa) may occur, especially for PTW traffic. 

According to ELSTAT data, the majority of road accidents and fatalities occur during clear sky, both inside and outside built-up area. However, accident severity is higher in rainy weatherand other weather conditions especially outside built up areas.  

A paper titled ‘A review of the effect of traffic and weather characteristics on road safety‘ co-authored by Athanasios Theofilatos and George Yannis is now published in Accident Analysis & Prevention. Taking into consideration the increasing availability of real-time traffic data and stimulated by the importance of proactive safety management, this paper attempts to provide a review of the effect of traffic and weather characteristics on road safety, identify the gaps and discuss the needs for further research. Despite the existence of generally mixed evidence on the effect of traffic parameters, a few patterns can be observed. For instance, traffic flow seems to have a non-linear relationship with accident rates, even though some studies suggest linear relationship with accidents. On the other hand, increased speed limits have found to have a straightforward positive relationship with accident occurrence. Regarding weather effects, the effect of precipitation is quite consistent and leads generally to increased accident frequency but does not seem to have a consistent effect on severity. The impact of other weather parameters on safety, such as visibility, wind speed and temperature is not found straightforward so far. The increasing use of real-time data not only makes easier to identify the safety impact of traffic and weather characteristics, but most importantly makes possible the identification of their combined effect. The more systematic use of these real-time data may address several of the research gaps identified in this research.  

A paper titled ‘Explaining the road accident risk: weather effects‘ co-authored by R.Bergel-Hayat, M.Debbarh, C.Antoniou and G.Yannis is now published in Accident Analysis and Prevention Journal. This research is based on some case studies carried out within the data analysis and synthesis activities of the EU-FP6 project “SafetyNet – Building the European Road Safety Observatory”, which illustrate the use of weather variables for analysing changes in the number of road injury accidents. Time series analysis models with explanatory variables that measure the weather quantitatively were used and applied to aggregate datasets of injury accidents for France, the Netherlands and the Athens region, over periods of more than twenty years. The main results reveal significant correlations on a monthly basis between weather variables and the aggregate number of injury accidents, but the magnitude and even the sign of these correlations vary according to the type of road (motorways, rural roads or urban roads).  

Road Safety by Seasonability in the EU is highlighted at the Traffic Safety Basic Facts 2012 available at the Road Safety Knowledge System of the DACOTA project within the framework of the European Road Safety Observatory of the European Commission. Although the annual number of people who died in road traffic accidents in Europe has fallen over many years, the distribution of the annual number by month has scarcely changed. Motorcycling is the mode of transport with the most seasonal fatality distribution. 

Road Safety by Seasonability in the EU is highlighted at the Traffic Safety Basic Facts 2011 recently released at the European Road Safety Observatory of the European Commission as prepared by the DACOTA project. Although the annual number of people who died in road traffic accidents in Europe has fallen over many years, the distribution of the annual number by month has scarcely changed. Motorcycling is the mode of transport with the most seasonal fatality distribution. 

A Diploma Thesis titled ‘Correlation of road accidents and weather conditions’  was presented by Dimitris Bilionis in July 2011. The purpose of this diploma thesis is to investigate the correlation between accident counts and basic meteorological conditions, such as rainfall and temperature. For this reason, analytical daily data were used for the number of accidents, fatalities and injuries, as well as for the temperature and the precipitation. The results show that the drop of temperature causes a decrease in the number of accidents, while an increase in precipitation causes a decrease in the number of accidents and fatalities as well. 

Road Safety by Seasonability in the EU is highlighted at the Traffic Safety Basic Facts 2010 recently released at the European Road Safety Observatory of the European Commission as prepared by the DACOTA project. Although the annual number of people who died in road traffic accidents in Europe has fallen over many years, the distribution of the annual number by month has scarcely changed. Motorcycling is the mode of transport with the most seasonal fatality distribution. 

The majority of road accidents and fatalities occurred during clear sky, both inside and outside built-up area. However, accident severity is higher in rainy weather, especially inside built-up areas. 

The Transportation Research Board (TRB) 89th Annual Meeting took place in Washington, D.C., in January 2010. NTUA presented ‘Weather Effects on Daily Traffic Accidents and Fatalities: A Time Series Count Data Approach‘ . The impact of weather conditions on traffic safety is a topic that has attracted considerable interest in the literature. 

The 4th Pan-Hellenic Road Safety Conference was organised by the Hellenic Institute of Transportation Engineers and the National Technical University of Athens.

NTUA presented:

 Characteristics of lorry and bus accidents in Greece

 Application of the SUNflower methodology for the assessment of two-wheeler safety in Greece

 Correlations of road accident and meteorological conditions time-series

 Seat belt and helmet use in Greece