Miejski eksperyment klimatyczny w Atenach - rozkład przestrzenny temperatury

This paper presents the main characteristics and the first results of a large scale experiment undertaken in Athens in the frame of the POLIS research program of the European Commission. Researches have been carried out to investigate the temperature distribution in the major Athens urban area. Twenty stations have been installed since June 1996 and the recorded data have been analyzed. A very important temperature increase has been recorded in the central Athens area. Energy analysis has been shown that temperature increase has a very important impact on the energy consumption of buildings for cooling purposes.Praca przedstawia główne charakterystyki i pierwsze wyniki eksperymentu podjętego na dużą skalę w Atenach w ramach POLIS - programu badawczego Komisji Europejskiej. Badania przeprowadzono w celu poznania rozkładu temperatury powietrza na obszarze Aten. Od czerwca 1996 r. uruchomiono 20 stacji pomiarowych i dokonano analizy uzyskanych danych. Zanotowano wyraźny wzrost temperatury w centrum Aten. Analiza wykazała, że wzrost temperatury wywiera istotny wpływ na ilość energii zużywanej na klimatyzację pomieszczeń

The distribution of rainy days in the Aegean area

The object of this study is the determination of the number of rainy days in the area of the Aegean sea, based on data obtained from 14 observation stations during the period 1950-1975. The results showed considerable differences from North to South. The seasonal number of rainy days as well as that of rainy spells were examined for the period 1950-1975. The spells of rainy days play an important role in the agricultural activities, especially over the southern part of the Aegean sea basin, where the annual amounts of rainfall are insufficient. From the data was concluded that during the summer, more than four consecutive rainy days were recorded at the northern most stations only and these of infrequent occurrence; whereas during the winter, it was possible to encounter up to 15 consecutive rainy days. Finally, we give a theoretical distribution for the rainy spells for each station and for each season and year, using Polya's method. We found that this distribution fitted well the 95% of the confidence level in the majority of the cases. © 1990 Springer-Verlag

Statistical and persistence analysis of high summer ambient temperatures in Athens for cooling purposes

The increase of living standards in buildings and the recent high summer temperature values have dramatically increased the installation of cooling systems in buildings. Analysis of the summer ambient temperatures is thus necessary in order to provide appropriate information to designers and to investigate possible increasing trends of ambient temperature having an important impact on energy consumption. A statistical analysis of the summer ambient temperature data is presented in order to provide information for evaluation of passive, hybrid and conventional cooling systems and techniques. Multiyear data of Athens, Greece, have been used. No statistically significant increasing or decreasing trend of the hot and very hot summer hours was found. The persistence of high summer temperatures was also calculated and found to be statistically significant. Probabilities of hourly temperatures being higher than a temperature base are calculated for each month. © 1991

The temperature of the sea-surface in the region of the Aegean and its relation to air temperature

In this study the annual course of the air and sea-surface temperature in the Aegean sea is examined and a possibly existing relation between these two meteorological parameters is sought. To do this the monthly values of both elements for the period 1971-1975 were cross-correlated. It was found that in general the observed delay of the maximum and minimum values of the temperature of the sea was of the order of one month. © 1990 Springer-Verlag

The temperature of the sea-surface in the region of the Aegean and its relation to air temperature

In this study the annual course of the air and sea-surface temperature in the Aegean sea is examined and a possibly existing relation between these two meteorological parameters is sought. To do this the monthly values of both elements for the period 1971-1975 were cross-correlated. It was found that in general the observed delay of the maximum and minimum values of the temperature of the sea was of the order of one month. © 1990 Springer-Verlag

The distribution of rainy days in the Aegean area

The object of this study is the determination of the number of rainy days in the area of the Aegean sea, based on data obtained from 14 observation stations during the period 1950-1975. The results showed considerable differences from North to South. The seasonal number of rainy days as well as that of rainy spells were examined for the period 1950-1975. The spells of rainy days play an important role in the agricultural activities, especially over the southern part of the Aegean sea basin, where the annual amounts of rainfall are insufficient. From the data was concluded that during the summer, more than four consecutive rainy days were recorded at the northern most stations only and these of infrequent occurrence; whereas during the winter, it was possible to encounter up to 15 consecutive rainy days. Finally, we give a theoretical distribution for the rainy spells for each station and for each season and year, using Polya's method. We found that this distribution fitted well the 95% of the confidence level in the majority of the cases. © 1990 Springer-Verlag

Statistical analysis of summer comfort conditions in Athens, Greece

Summer comfort condition in Athens, Greece, have been analyzed statistically. The temporal variation of the number of hours inside the comfort zone as well as the corresponding frequency distribution have been calculated. The persistence of discomfort conditions has been analyzed and was found to be statistically significant for comfort and discomfort spells presented during the period May to September. The calculated duration of the spells inside or outside the comfort zone for May, July and August extend up to 20 consecutive hours, while for June and September the corresponding duration is 15 consecutive hours. © 1993

Frequency analysis of the high SO2 and smoke concentrations over Athens

This paper presents the results from a statistical study of SO2 and smoke concentration data recorded by the urban Athens area network. For the study it was necessary to examine the frequency distribution and the return period of the high concentration cases alongside the prevailing meteorological conditions. This was necessary as there were significant differences in the pollutant concentrations between the warm and cold period of the year. Furthermore it was found that temperature inversions and rainfall played an important role for both SO2 and smoke. This paper focuses on SO2 and smoke concentrations only since there was a long and reliable time series of recorded data. © 1991