A5050775113- Atmospheric Ozone and Climate
- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Atmospheric aerosols and clouds
- Calibration and Measurement Techniques
- Air Quality Monitoring and Forecasting
- Water Quality Monitoring and Analysis
- Geochemistry and Geologic Mapping
- Climate variability and models
- Urban and Freight Transport Logistics
- Radioactivity and Radon Measurements
- Traffic Prediction and Management Techniques
- Solar Radiation and Photovoltaics
- Methane Hydrates and Related Phenomena
- Transportation Planning and Optimization
- Hydrocarbon exploration and reservoir analysis
- Astro and Planetary Science
- Spectroscopy and Laser Applications
- Meteorological Phenomena and Simulations
Aristotle University of Thessaloniki
2002-2025
Indian Institute of Technology Roorkee
2021
The COllaborative Carbon Column Observing Network has become a reliable source of high-quality ground-based remote sensing network data that provide column-averaged dry-air mole fractions carbon dioxide (XCO2), methane (XCH4), and monoxide (XCO). fiducial reference measurements these gases from the COCCON complement TCCON NDACC-IRWG data. This study shows application for validation existing greenhouse gas satellite products. includes XCH4 XCO products European Copernicus Sentinel-5 Precursor...
In this work, column-averaged dry-air mole fractions of carbon dioxide (XCO2), methane (XCH4) and monoxide (XCO) are presented for the first time at a mid-latitude urban station, Thessaloniki, Greece, using Bruker EM27/SUN ground-based low-resolution Fourier Transform spectrometer operated according to requirements Collaborative Carbon Column Observing Network (COCCON). Two years measurements examined seasonal variability. The observed XCO2 levels show expected cycle (spring maximum, late...
Abstract. This study introduces an Earth observation (EO)-based system which is capable of operationally estimating and continuously monitoring the ultraviolet index (UVI) in Europe. UVIOS (i.e., UV-Index Operating System) exploits a synergy radiative transfer models with high-performance computing EO data from satellites (Meteosat Second Generation Meteorological Operational Satellite-B) retrieval processes (Tropospheric Emission Monitoring Internet Service, Copernicus Atmosphere Service...
Increasing concentrations of greenhouse gases (GHGs) in the atmosphere are primary driver observed rise global surface temperatures, meanwhile exceeding 1°C above pre-industrial levels. Addressing this challenge requires linking GHG to specific anthropogenic and natural sources as part carbon budget. This study investigates relationship between measured Thessaloniki, Greece, potential long-range transport using a clustering approach.The data were obtained from EM27/SUN Fourier...
Increased concentrations of greenhouse gases in the atmosphere have resulted a rise Earth's average temperature last decades. Methane (CH4), second most important anthropogenic gas after carbon dioxide (CO2), is considered to be 2.6 times higher than pre-industrial levels (Jackson et al., 2024). CH4 28 more efficient at trapping heat CO2 over 100-year period and 80 powerful 20 years, even though it present smaller quantities has shorter lifespan CO2. A special interest lies...
The actinic flux describes the number of photons incident at a point, while irradiance radiant energy crossing surface. An algorithm for conversion to downwelling has been developed and tested. uses simple method distinguish between cloudy cloudless sky. It is necessary separate situations, as depends on radiance field which rather different skies. Surface UV spectra were measured five European locations representative climates. A total 9015 synchronized available test proposed algorithm....
Results are presented from the Actinic Flux Determination Measurements of Irradiance (ADMIRA) campaign to measure spectral global UV irradiance and actinic flux at ground, beneath an atmosphere well defined by supporting measurements. is required calculate photolysis rates for atmospheric chemistry, yet most measurements irradiance. This work represents first part a project provide algorithms converting irradiances fluxes with specified uncertainties. The took place in northern Greece August...
Multiband filter radiometers (MBFRs) are extensively used in national measurement networks for UV climate monitoring and informing the public about potential health risks from excessive solar exposure. Results first international intercomparison of MBFRs, arranged Oslo 2005, presented. Forty‐three type GUV, NILU‐UV, UVMFR‐7 were assembled, representing stations on several continents. The objective was to conduct a blind Global Index (UVI) processed by instrument owners. Eleven independent...
Abstract. Ultraviolet radiation is the key factor driving tropospheric photochemistry. It strongly modulated by clouds and aerosols. A quantitative understanding of field its effect on photochemistry thus only possible with a detailed knowledge interaction between radiation. The overall objective project INSPECTRO was characterization three-dimensional actinic under cloudy conditions. This achieved during two measurement campaigns in Norfolk (East Anglia, UK) Lower Bavaria (Germany)...
Abstract. An empirical approach for the retrieval of nitrogen dioxide (NO2) and formaldehyde (HCHO) photolysis frequencies from measurements global irradiance is presented in this work. Four months synchronous actinic flux performed Thessaloniki, Greece by a Bentham spectroradiometer were used to extract polynomials conversion [J(NO2) J(HCHO)]. The comparison these frequency values corresponding calculated spectral measurements, showed ratio very close unity all J's with standard deviation...
To quantify the effect of ambient temperature on voltage signal Solar Light UV-Biometers, spectral response functions two instruments were determined in laboratory under various external conditions. Despite biometer's internal stabilization, a increase 20 degrees C at outside an instrument's housing resulted reduction by as much 10% UVB range and factor 2 UVA range, depending individual instrument its relative humidity. The significance this for outdoor measurements is demonstrated data from...
The stratospheric ozone depletion during the last two decades, increase of UV-B irradiance levels at ground and possible impact on biosphere has led scientists to develop use instruments high accuracy for UV measurements. During years, 9 stations have been established in different environments Greece Cyprus, with aim establish a long-term monitoring network. network (NILU-UV multichannel filter radiometers) can provide measurements visible part solar spectrum. In this study, first results...
Carbon monoxide, XCO, and methane, XCH4, column-averaged dry-air mole fractions (DMFs), observed by the TROPOspheric Monitoring Instrument (TROPOMI) on board Sentinel-5P (S-5P), are validated against those obtained from a Bruker ground-based low-resolution Fourier transform spectrometer, EM27/SUN, operating in framework according to requirements of Collaborative Column Observing Network (COCCON), Thessaloniki, Greece, mid-latitude urban site. The current operational S5P/TROPOMI observations...
Abstract. The results of two methods retrieving actinic flux and ozone photolysis frequencies (JO1D), from measurements irradiance with a Brewer MKIII spectroradiometer are investigated in this paper. first method uses retrieved by the use known formulas while second is an empirical converting to JO1D through polynomials extracted study synchronous measurements. When examining fluxes derived those measured spectrometer data agree within ±10% for solar zenith angles lower than 75° UV-B UV-A...
Abstract. Ultraviolet radiation is the key factor driving tropospheric photochemistry. It strongly modulated by clouds and aerosols. A quantitative understanding of field its effect on photochemistry thus only possible with a detailed knowledge interaction between radiation. The overall objective project INSPECTRO was characterization three-dimensional actinic under cloudy conditions. This achieved during two measurement campaigns in Norfolk (East Anglia, UK) Lower Bavaria (Germany)...
A portable Bruker EM27/SUN FTIR (Fourier Transform InfraRed) spectrometer is operated in the urban area of Thessaloniki, Greece since January 2019, frame COllaborative Carbon Column Observing Network (COCCON), performing measurements total column-averaged dry air mole fractions trace gases. Main target gases are greenhouse carbon dioxide (CO2), methane (CH4) and monoxide (CO). In this paper we investigate seasonal dependency between CO-CO2 CO-CH4 enhancements with respect to prevailing wind...
The issue of atmospheric pollution in urban centers has become a growing concern recent years. increasing levels greenhouse gases the atmosphere are major contributor to pollution, and it is imperative monitor these gases. This study presents measurements column-averaged dry-air mole fractions carbon dioxide (XCO2) monoxide (XCO) Thessaloniki, Greece. were taken Thessaloniki using Bruker EM27/SUN instrument, which was developed by KIT been part Collaborative Carbon Column Observing Network...
<p>The column-averaged dry air mole fractions of carbon dioxide (XCO<sub>2</sub>), methane (XCH<sub>4</sub>) and monoxide (XCO) have been measured for the first time a whole year in Thessaloniki, Greece, using portable Bruker EM27/SUN ground-based low-resolution Fourier Transform spectrometer, provided by Karlsruhe Institute Technology. The is reliable, easy-to-deploy, mobile, low-cost supplement to IFS...
Multiband filter radiometers (MBFRs) are extensively used in national networks for UV climate monitoring and information to the public about potential risk of solar exposure. In order provide an international, uniform expression Global index measurements, a harmonized calibration scale is needed. this paper we present results first international intercomparison MBFRs held Oslo 2005. The purposes evaluate UV-index different based on individual directional absolute spectral response functions....
Abstract. A study on the estimation of J(O1D) and J(NO2) photolysis frequencies when limited ground based measurements (or even no at all), are available is presented in this work. Photolysis can be directly measured by chemical actinometry filter radiometry or calculated from actinic flux measurements. In several meteorological stations, none methods above applicable due to absence sophisticated instruments such as actinometers, radiometers spectroradiometers. case, it possible calculate...