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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 the framework and according to requirements of the Collaborative Carbon Column Observing Network (COCCON), in Thessaloniki, Greece, on a mid-latitude urban site. The current operational S5P/TROPOMI observations show very good agreement with the respective FTIR measurements and capture both their seasonal variability and pollution episodes. XCO reported the highest concentrations during the fire episodes in summer 2021, when its daily mean value reached a maximum of 0.134 ± 0.015 ppm. XCH4 shows a slight annual increase of 0.02 ppm, with the highest concentrations during early 2022 (approximately 1.92 ppm). The satellite CH4 and CO products have been recently reprocessed with updated CH4, CO and H2O cross-sections, among other improvements, bringing noticeable changes in the pre-existing biases of S5P products against the FTIR ground-based data. We report that, for this mid-latitude station, mean biases and standard deviations fall well within mission requirements for XCH4 and XCO (-0.01 ± 0.6% and 0.62 ± 4.2% for XCH4 and XCO, respectively), underlying the significance of satellite measurements as a valuable supplement to ground-based data for the purpose of greenhouse gas monitoring. The results presented in this work for the Thessaloniki FTIR instrument are in strong agreement with FTIR locations in the middle latitudes. [ABSTRACT FROM AUTHOR]

In the present study, the introduction of the Innovative Polygon Trend Analysis (IPTA), a non-parametric trend analysis methodology, is proposed as an alternative to the classical trend analysis methodology, according to which processes (normality, independence, and pre-whitening) are not necessary. Monthly precipitation measurements from Thessaloniki are analysed for the period 1971-2020, subdivided into two consecutive equal periods, to identify inherent trends among months and seasons, respectively. A finer interpretation of trends, with physical and numerical explanations and inferences, leads to the obtained results; the total monthly and seasonal precipitation values, their associated standard deviations, as well as trend slopes and trend lengths, are depicted. Increasing trends between the two sub-periods are identified for most months: winter and autumn. [ABSTRACT FROM AUTHOR]

During the last few years, extremely high temperatures have been recorded in many Greek regions and, in some cases, have been rather abnormal for each season. These extreme events appear to be persistent in duration and are occurring at a disconcerting frequency. The main objective of this study is to examine the exceptionally high temperatures that were recorded during January 2023 in Thessaloniki, Greece. The entire month was characterized by minimum and maximum temperatures that exceeded the climatological mean (1961-2000) by about 4.2 °C on average. Additionally, the average deviation for the mean maximum temperature of the month was calculated at 3.5 °C. In an attempt to classify the intensity of this possible extreme event compared to a future intermediate emission scenario (RCP4.5), a comparison of the observational data with the corresponding data from two future projections (2041-2060 and 2081-2100) of a high-resolution regional climate model was carried out. The spatial resolution of the simulations was 10 x 10 km and they were the result of the dynamical downscaling of the RegCM regional climate model after nesting a 25 km simulation of the model for the initial and boundary conditions. Finally, through this study, the contribution of the synoptic-scale atmospheric conditions of this event was examined. [ABSTRACT FROM AUTHOR]

The issue of atmospheric pollution in urban centers has become a growing concern in recent years. The increasing levels of greenhouse gases in the atmosphere are a major contributor to atmospheric pollution, and it is imperative to monitor these gases. This study presents the measurements of column-averaged dry-air mole fractions of carbon dioxide (XCO2) and carbon monoxide (XCO) in Thessaloniki, Greece. The measurements were taken in Thessaloniki using the Bruker EM27/SUN instrument, which was developed by Bruker and KIT and has been part of the Collaborative Carbon Column Observing Network (COCCON) since 2018. COCCON is a global network of stations around the globe and serves as an important supplement to the high-resolution Bruker IFS125 spectrometer used in the Total Carbon Column Observing Network (TCCON), and it provides an increased density of column-averaged greenhouse gas observations. In this work, a four-year analysis of column-averaged dry-air mole fractions of XCO2 and XCO is presented, focusing on diurnal and seasonal cycles as well as on the comparison between them. The hourly time series show the expected seasonal cycle of XCO2 with a spring maximum and late summer minimum due to photosynthesis activity, while XCO2 presents a daily maximum of 419.987 ± 2.286 ppm and a daily minimum of 405.001 ± 3.067 ppm. The seasonal co-variability between XCO2 and XCO reveals an interesting correlation--especially during winter (R² = 0.841 for 2022) and spring (R² = 0.437 for 2022) period, when anthropogenic emission sources occur. [ABSTRACT FROM AUTHOR]

Τhe Renaissance of 19th-century historiography and of every period of intense artistic and intellectual activity called renaissance is characterized by the exploration of cultural heritage that it inherits and its appropriation, conquest, and revival through this exploration. We are referring to the Carolingian renaissance, the Ottoman, the 12th century one, and the Italian Renaissance with its chronological subdivisions and influences. Corresponding renaissances are also recognized in the Byzantine territory. The Macedonian, the Komnenian and the Palaiologan renaissance, until Byzantium transitionsto the Ottoman occupation, during the period that the Quattrocento culminated. The difficulty in the periodization of renaissances is argued to be an element of the historical continuum. Also, the repeatability of the characterization of periods as renaissance supports the evolutionary continuity between antiquity and modern times, as ancient knowledge was never wholly absent from the West or Byzantine society. After all, in one way or another, historians today agree that this division is always made up. In this article, we focus on the impact of the so-called renaissance periods on monuments, urban planning and the fortification of Thessaloniki. We approach this by defining the elements that constitute a renaissance in architecture and whether this phenomenon concerns changes in social and political issues, with what characteristics, or only in architectural practices. The purpose is to understand whether the perception of the renaissance characteristics of a period is objective or is confined to artificial periodization. We explore why a period acquires renaissance characteristics, attempting to appropriate the glorious past and consequently of its authoritarian power. We examine when it is characterized as a renaissance, purifying the policies in the name of the superiority that a renaissance represents. In this way, we understand that the concept of renaissance, which by definition is characterized by the opening up of all intellectual fields, tends to construct new borders, geographical, political, cultural. [ABSTRACT FROM AUTHOR]

Port city of Thessaloniki, since its foundation in 316 BC, has sustained its prestige as an important commercial and settlement center and has developed under the regime of different empires such as Roman, Byzantine and Ottoman. The city served under the Ottoman Empire from 1430 to First Balkan War in 1912. During the Ottoman period, Thessaloniki's Turkish Muslim population has grew. By the start of the 16th century, the boundaries of the Muslim neighbourhoods came to be the largest within the city while the Christian neighbourhoods around important Byzantine monuments started to shrink and shatter. Principal groups of 16th century Thessaloniki, Turkish, Rum and Jewish populations, had settled in different quarters of the city. Thus, the urban fabric of Turkish, Rum and Jewish neighbourhoods were affected by the cultural, social, economic, and religious aspects of their communities. The architectural fabric of 16th century Thessaloniki mainly consisted of the residential fabric with public and religious buildings. This urban settlement in Thessaloniki existed until the start of the 20th century. The Muslim neighbourhoods which were the major part of the urban fabric were given form by the traditional Ottoman architecture. As a consequence of the cultural, religious and social aspects of the Muslim folk's lifestyle, every neighbourhood gathered around a central mosque. New mosques were constructed or converted from churches to fulfill the needs of the Muslim neighbourhoods. In addition to mosques, madrasa and bath structures were built for the daily needs of the public. These artifacts make up the major part of the Ottoman architectural heritage and their remains are the main source of information about the social and architectural character of the period. Thus, in this paper the neighbourhood map of Thessaloniki of 1525 will be analyzed in terms of Thessaloniki's neighbourhood and architectural fabric in 16th century and the architectural artifacts of this period will be inspected together with their present state. This paper is based on the book: "Kültür Köprüleri 1. Selanik ve Kavala Bölgelerinde Osmanlı Türk Mimari Mirası". [ABSTRACT FROM AUTHOR]

The present paper investigates the characteristics of the Urban Heat Island (UHI) in the Greater Thessaloniki Area (GTA). The study is carried out by using and analyzing hourly air temperature data covering the period from June through September 2008. It was found that the urban zone of the city is heated faster and more effectively than the suburban surroundings, especially in early morning hours. Two measuring sites were selected as representative of “urban” and “suburban” areas and the hourly air temperature differences were calculated and classified by magnitude. The analysis of the percentage of occurrences for each class revealed that the city of Thessaloniki is subject to a rather moderate UHI. It was also found that the heat island can be more clearly observed during overnight hours, reaching, however, its maximum magnitude in early morning hours. Last but not least, the current paper introduces the development of an Urban Heat Island Forecasting Service (UHI-FS). [ABSTRACT FROM AUTHOR]