Aristides Bartzokas

Aristides Bartzokas
University of Ioannina | UOI · Department of Physics

Professor

About

180
Publications
28,095
Reads
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2,826
Citations
Additional affiliations
January 1993 - December 2012
University of Ioannina
Education
September 1984 - September 1989
University of Ioannina
Field of study
  • Meteorology - Climatology
September 1979 - June 1981
University of Birmingham
Field of study
  • Meteorology - Climatology
September 1974 - June 1979

Publications

Publications (180)
Article
Α new method, based on the definition of Weather Types (WTs), for the determination of seasons in the Mediterranean region is adopted. This method combines Principal Component Analysis and k‐means Cluster Analysis on daily grid point meteorological data for the 70‐year period 1949‐2018 obtained from the NCEP/NCAR database. At first, the method is a...
Article
Full-text available
In this paper, the factors that determine the particulate matter concentrations with diameter less than 10μm (PM10) are investigated for the provincial city of Ioannina, NW Greece. The analysis reveals that even in a generally medium-sized city as Ioannina (120,000 habitants), PM10 levels exceed the European Union’s standards (mean daily PM10<50 μg...
Article
An objective definition of seasons for the Mediterranean region is performed using the mean intra‐annual variations of 12 climatological parameters. The aim is to achieve a climatologically appropriate determination of the onset and cessation dates, as well as the duration, of each season, better than the conventional seasons (winter, spring, summe...
Article
Full-text available
Rain monitoring through signal attenuation has been a significant concern for the scientific community over the last decade. The lowest L-, Sand C-bands in the microwave spectrum are full of potential for environmental monitoring devices. It has not been extensively proven whether signal attenuation can be used for rain estimation throughout the mi...
Article
The influence of the large-scale atmospheric circulation on winter precipitation over the Mediterranean region is studied with the use of monthly 2.5° × 2.5° ERA-Interim 500 and 1000 hPa geopotential heights and GPCP-v2.3 precipitation, for the period 1980–2017. At first, Principal Component Analysis (PCA) is applied both to geopotential heights an...
Article
An objective definition of climatologically homogeneous areas in the southern Balkans is attempted with the use of daily 0.25° × 0.25° ERA5 meteorological data of air temperature, dew point, zonal and meridional wind components, Convective Available Potential Energy, Convective Inhibition, and total cloud cover. The classification of the various gr...
Conference Paper
The effect of the atmospheric circulation on the sea surface parameters of the Mediterranean and the Black Seas is studied for the 50-year period 1958-2007, during winter. The dataset consists of monthly (November-March) anomalies of: i) sea surface temperature, sensible and latent heat flux, short and long wave radiation and total cloud cover for...
Conference Paper
Full-text available
The influence of the large-scale atmospheric circulation characteristics on the winter precipitation over the Mediterranean region is studied with the use of monthly 2.5°x2.5° ERA-Interim 500hPa and 1000hPa geopotential heights and GPCP-v2 precipitation, for the period 1980-2017. At first, Principal Component Analysis (PCA) is performed on both geo...
Conference Paper
Full-text available
The effect of the atmospheric circulation on the sea surface parameters of the Mediterranean and the Black Seas is studied for the 50-year period 1958-2007, during winter. The dataset consists of monthly (November-March) anomalies of: i) sea surface temperature, sensible and latent heat flux, short and long wave radiation and total cloud cover for...
Conference Paper
Full-text available
Fluctuations in soil temperatures are important factors in determining natural and energy processes at the ground-atmosphere system. Changes in meteorological parameters are reflected in soil temperatures, with the influence being more pronounced in the upper layer of the soil. In this paper the variations of temperatures of air, surface and the so...
Article
Full-text available
In this paper we present an experimental validated system for measuring rainfall due to radio frequency (RF) signal attenuation at 2 GHz. Measurements took place in Ioannina, NW Greece, starting in April 2015 and lasting for twelve months. The primary acquired extensive results have shown reliable and accurate measurements for rainfall amounts smal...
Article
The diurnal course of daylight (exterior illuminance) during winter and summer in a central European town, Bratislava, Slovakia, is studied. By using multivariate statistical methods (Factor and Cluster Analysis), the most significant types of the diurnal variations of illuminance are determined. The database used consists of mean 5-min values of g...
Conference Paper
In this work we present an accurate and costeffective system for measuring S-band signal attenuation due to rainfall. The system is based on a pair of transmitter and receiver, operating at the lower limit of Sband, i.e. 2 GHz, separated at few meters distance and thus at any instant the rain’s strength is uniform at this short path. The system is...
Article
Full-text available
The Indian summer monsoon (ISM) is a prominent feature of the summer circulation in the Northern Hemisphere (NH) and has been found to modulate the weather and climate conditions in many remote regions. This study investigates the most recurrent patterns of summertime midlatitude circulation, over the eastern Mediterranean (EM) and also globally, t...
Chapter
Full-text available
In this work, the diurnal and the intra-annual variations of soil temperatures in Ioannina, NW Greece, are studied at the earth’s surface and at depths 10, 20, 30 and 60 cm, along with the air temperature, for a 7-year period. Temperature of the soil at the earth’s surface is higher than air temperature and it increases with depth in autumn and win...
Conference Paper
This paper introduces a new climatology index, the Caspian Sea—Hindu Kush Index (CasHKI), which consists of changes in the mean sea level pressure (MSLP) gradient between the Caspian Sea (CS, 40–50 °N, 50–55 °E) and Hindu Kush (HK, 35–40 °N, 70–75 °E) which modulate the atmospheric dynamics and dust activity over southwest (SW) Asia. The CasHKI is...
Article
The seasonal variability of cloudiness in the Mediterranean region is studied, through the examination of the mean day-to-day intra-annual variation of gridded NCEP/NCAR total cloud cover for the period 1948-2014. A dimensionality reduction process is followed by using a multivariate statistical methodology and three main modes of seasonal variatio...
Article
The spatio-temporal regime of lightning strokes over the broader Greek area is studied using 15-day ZEUS cloud-to-ground lightning data for a 10-year period (2005–14). The multivariate statistical method Factor Analysis (S-mode and T-mode) is applied on the mean intra-annual variation of lightning in order to reveal: i) the main modes of intra-annu...
Article
Objective: To evaluate the relationship between meteorological factors in North-western Greece and the incidence of bronchiolitis. Methods: Meteorological data (air temperature and rainfall) for Ioannina city in North-western Greece and medical data from hospitalised patients at University Hospital of Ioannina were collected between January 2002...
Article
This study examines the influence of the Caspian Sea–Hindu Kush Index (CasHKI) on local and synoptic meteorology as well as on dust emissions over southwest (SW) Asia by means of National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP-NCAR) re-analysed mean sea-level pressure (MSLP), geopotential height at 700 hPa...
Article
This study examines the influence of the Caspian Sea–Hindu Kush Index (CasHKI) on local and synoptic meteorology as well as on dust emissions over southwest (SW) Asia by means of National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP-NCAR) re-analysed mean sea-level pressure (MSLP), geopotential height at 700 hP...
Chapter
The main characteristics of atmospheric circulation favoring extreme daily minimum surface air temperatures over the Mediterranean region are studied. NCEP/NCAR Reanalysis grid point daily values of minimum surface air temperature (Tmin), 500 hPa and 1000 hPa geopotential heights (Z500 and Z1000) and 850 hPa air temperature (T850) over the Mediterr...
Chapter
An intense and fast moving convective line that crossed Massif Central/Cévennes—Vivarais area (south France) during the field campaign of HYdrological cycle in Mediterranean EXperiment (HyMeX)—Special Observing Period 1 (SOP1) is examined. The mesoscale analysis demonstrates a complex convective system with a V-shape in the Infrared (IR) satellite...
Chapter
Full-text available
The prevention and confrontation of natural hazards during extreme weather conditions constitute an educational subject usually provided by bodies such as the meteorological service or environmental education, health education and educational mobility programs. In such actions, Information and Communication Technologies (ICT) have a dominant role,...
Chapter
In this work, the ability of a long-range weather forecast via the folklore “Merominia” is investigated in detail. Merominia are called either the first twelve days of August or the days from the 14th to the 25th of August. According to local traditions and beliefs, by observing the weather of these days, someone can forecast the weather of a whole...
Chapter
Τhe diurnal variation of illuminance during winter is studied in Bratislava, Slovakia. The database consists of mean 5-min values of global horizontal illuminance (CIE IDMP station 48.17°N, 17.08°W, alt. 195 m) around winter solstice (26 November–6 February, up to 110 % of solstice day length) for the 14-year period 1994–2007. Two separate sets of...
Chapter
The influence of the atmospheric circulation over Europe, the east Atlantic and north Africa on the sea surface of the Mediterranean and the Black Seas is studied for the 50-year period 1958–2007, during summer. The dataset consists of monthly (May-September) anomalies of: (i) sea surface temperature, sensible and latent heat flux, short and long w...
Chapter
The seasonal variability of total cloud cover in the Mediterranean region is studied, using NCEP/NCAR daily grid point data. The mean day to day intra-annual variations of total cloud cover during the hydrological year (1 October–30 September) are extracted for the 66-year period 1948–2014. A dimensionality reduction method is applied on the 324 ti...
Chapter
The intra-annual variation and the spatial distribution of lightning activity over Greece is studied for the 10-year period 2005–14, on a 15-day basis, using Zeus 0.5° × 0.5° data. Factor Analysis (S-mode and T-mode) is applied to the average lightning activity for each fortnight of the year and for each grid box, for the studied period. (i) For th...
Article
An intense and fast moving convective line that crossed Massif Central/Cévennes - Vivarais area (south France) during the field campaign of Hydrological Cycle in Mediterranean Experiment (HyMeX) - Special Observing Period 1 (SOP1) is examined. The mesoscale analysis demonstrates a complex convective system with a V- shape in the Infrared (IR) satel...
Article
The precipitation regime over the Mediterranean basin is investigated for the period 1979–2010 using monthly mean satellite data from the Global Precipitation Climatology Project (GPCPv2). The results show that a clear contrast exists between the more rainy northern part of the study region (Southern Europe) and the drier southern area (North Afric...
Article
Monthly mean satellite data from the Global Precipitation Climatology Project (GPCPv2) are used to examine the year-by-year variability of precipitation over the Mediterranean Basin and its changes over the period 1979–2010. The results show that the mean annual precipitation averaged over the study area has slightly increased from 1979 to 2010 by...
Article
The realization of Renewable Energy Sources (RES) for power generation as the only environmentally friendly solution, moved solar systems to the forefront of the energy market in the last decade. The capacity of the solar power doubles almost every two years in many European countries, including Greece. This rise has brought the need for reliable p...
Article
The realization of Renewable Energy Sources (RES) for power generation as the only environmentally friendly solution, moved solar systems to the forefront of the energy market in the last decade. The capacity of the solar power doubles almost every two years in many European countries, including Greece. This rise has brought the need for reliable p...
Article
Full-text available
Extreme Data is an incarnation of Big Data concept distinguished by the massive amounts of data that must be queried, communicated and analyzed in near real-time by using a very large number of memory or storage elements and exascale computing systems. Immediate examples are the scientific data produced at a rate of hundreds of gigabits-per-second...
Article
The connection between atmospheric circulation over Europe and snowfall in Ioannina, Northwestern (NW) Greece, is examined. The study deals with 160 snow events, referring to the 56-year period 1956–2011. For each of the events, the patterns of 500 and 1000 hPa geopotential height, 500 and 850 hPa air temperature, 1000–500, 1000–700 and 700–500 hPa...
Article
Background: Human anthrax is currently a sporadic disease in Europe, without significant regional clustering. Objective: To report an unexpected aggregate of anthrax cases and correlate local climatic factors with yearly anthrax admissions. Methods: Clinical description of a geographical-temporal anthrax aggregate, correlation of disease admis...
Conference Paper
Full-text available
An intense and fast moving convective line that crossed Massif Central/Cévennes - Vivarais area (south France) during the late night of 23 September and early morning of 24 September 2012, during the field campaign of HyMeX - Special Observing Period 1 (SOP1) is examined. The mesoscale analysis demonstrates a complex convective system with a V- sha...
Conference Paper
Full-text available
The case of a rare tornadic-supercell, which caused severe structural and forest damage in the town of Ioannina (Northwest Greece) on 2 December 2014 is examined. The synoptic and mesoscale conditions associated with the event are studied using the Weather Research and Forecasting (WRF) model, applying a two-way nesting technique of three domains w...
Conference Paper
Full-text available
The realization of Renewable Energy Sources (RES) for power generation as the only environmentally-friendly solution, moved solar systems to the forefront of the energy market in the last decade. The capacity of solar power doubles almost every two years in many European countries, including Greece. This rise has brought the need for reliable predi...
Conference Paper
A comparative study of Precipitable Water (PW) estimates derived from GPS observations and predicted from the MM5 meteorological model was conducted for 8 locations in Northwestern Greece. GPS receivers were available at the selected locations as part of the Leica’s Smartnet GNSS reference station in Greece. Zenith tropospheric delays were estimate...
Article
In this work the impact of topography on the distribution and the amount of precipitation in Epirus, NW Greece is investigated, during the cold period of the year. A precipitation event with typical wintertime characteristics is considered. In the selected case, extended and heavy precipitation over Epirus is caused by a low pressure system centred...
Article
A rapid development of solar energy systems has been noticed in the last decade worldwide, with the photovoltaic systems’ installed global power capacity exceeding 100GWe. Moreover, the European Union has realized that one of the key sectors for the implementation of energy saving techniques is the building sector for which Member States have alrea...
Article
In the present study, the cases of atmospheric circulation evolution favouring the occurrence of Desert Aerosol Episodes (DAEs) over the broader Mediterranean region are investigated using an objective and dynamic algorithm, with daily satellite data for the period 2000–2013. After identifying strong and extreme DAEs, at 1°x1° geographical cell lev...
Article
The degree-day method is considered to be a fun-damental and a rather simple method to estimate heating and cooling energy demand. This study aims in a detailed and accurate assessment of cooling and heating degree days in different locations within the Greater Athens area (GAA), Greece. To achieve this goal, hourly values of air temperature from e...
Article
Dust storms are considered natural hazards that seriously affect atmospheric conditions, ecosystems and human health. A key requirement for investigating the dust life cycle is the analysis of the meteorological (synoptic and dynamic) processes that control dust emission, uplift and transport. The present work focuses on examining the synoptic and...
Conference Paper
Full-text available
The present work focuses on examining the synoptic and dynamic meteorological conditions associated with dust-storm outbreaks in the Sistan region, southeastern Iran during the summer season (June-September) of the years 2001 to 2012. The dust-storm days (total number of 356) are related to visibility records below 1 km at Zabol meteorological stat...
Conference Paper
Full-text available
Τhe diurnal variation of illuminance during summer is studied in Bratislava, Slovakia. The database consists of mean 5-minute values of global horizontal illuminance (CIE IDMP station - 48.17N, 17.08E, alt. 195m) around summer solstice (2 May - 8 August, up to 90% of solstice day length) for the 14-year period 1994-2007. Two sets of data are determ...
Conference Paper
Full-text available
The main atmospheric circulation characteristics favouring precipitation in Cyclades Islands, southern Aegean, are examined. The data used consist of daily values of: 1) precipitation at the meteorological stations of Naxos, Santorini and Milos and 2) temperature, humidity and circulation parameters at 2.5x2.5 degrees grid over Europe (NCEP/NCAR),...
Article
Full-text available
The present study focuses on identifying the main atmospheric circulation characteristics associated with aerosol episodes (AEs) over Kanpur, India during the period 2001–2010. In this respect, mean sea level pressure (MSLP) and geopotential height of 700 hPa (Z700) data obtained from the NCEP/NCAR Reanalysis Project were used along with daily Terr...
Article
Full-text available
The present study focuses on identifying the main atmospheric circulation characteristics associated with aerosol episodes (AEs) over Kanpur, India during the period 2001–2010. In this respect, mean sea level pressure (MSLP) and geopotential height of 700 hPa (Z700) data obtained from the NCEP/NCAR Reanalysis Project were used along with daily Terr...
Article
Full-text available
The present study focuses on identifying the main atmospheric circulation characteristics associated with aerosol episodes (AEs) over Kanpur, India during the period 2001-2010. In this respect, mean sea level pressure (MSLP) and geopotential height of 700 hPa (Z700) data obtained from the NCEP/NCAR Reanalysis Project were used along with daily Terr...
Article
Full-text available
The climate characteristics of summer human thermal discomfort in Athens and its connection to atmospheric circulation is studied for the period 1954-2012. The human thermal discomfort is examined in terms of the Predicted Mean Vote (PMV) discomfort index for calm and light wind (3 m/s) conditions. Its inter-annual variability is characterized by a...
Conference Paper
Full-text available
The aim of this work is to investigate if and to what extend the most important lakes of Epirus (NW Greece), namely. Ioannina and Metsovo Lakes, affect the precipitation regime (height and distribution) in the area during the warm period of the year. For this reason, afternoon thermal precipitation events are considered and simulated by applying th...
Conference Paper
Full-text available
The Indian summer monsoon (ISM) is a key factor influencing the eastern Mediterranean climate. During early summer period, the thermal low over Pakistan and northwestern India extends towards the Mediterranean through inner Iraq and Turkey. On the other hand, the Azores high expands eastwards and meets the Balkan high pressure system, forming one c...
Chapter
Full-text available
In this paper the wind energy in northwestern Greece is studied at 80 m above ground level. The MM5 meteorological model is used to obtain the necessary wind data to estimate the wind energy potential. This model is used operationally by the Laboratory of Meteorology of Ioannina University for daily weather forecast. The model runs in 3 domains (Eu...
Article
In this work Artificial Neural Networks (ANNs) were developed and applied in order to forecast the discomfort levels due to the combination of high temperature and air humidity, during the hot season of the year, in eight different regions within the Greater Athens Area (GAA), Greece. For the selection of ANNs-forecasting models best type and archi...
Article
The seasonal characteristics of atmospheric static stability in the Mediterranean region are examined, for the 60-year period 1948-2007 and for the four 15-year sub-periods 1948-1962, 1963-1977, 1978-1992 and 1993-2007. S-Mode and T-Mode Factor Analysis are applied to the mean 5-day values of K static stability index over the Mediterranean region....
Article
The evolution of the atmospheric circulation over Europe and the Mediterranean during fog events in Ioannina, north-western Greece, is examined for the period 1957-2002. A 24-hour period starting at 12:00UTC is defined as a fog day, when at least one of the present and/or past weather codes of the corresponding SYNOPs refers to fog. A sequence of s...
Article
Full-text available
Atmospheric circulation patterns that are conducive to extreme ocean heat loss are investigated at four sites of special interest in the Mediterranean Sea. The Gulf of Lions, the South Adriatic Sea, the Cretan Sea, and the Levantine Sea are all areas, where anomalously high winter heat loss may lead to deep or intermediate water formation. At each...
Article
Full-text available
The mesoscale meteorological model MM5 is applied to 22 selected days with intense precipitation in the region of Epirus, NW Greece. At first, it was investigated whether and to what extend an increased horizontal resolution (from 8 to 2 km) improves the quantitative precipitation forecasts. The model skill was examined for the 12-h accumulated pre...