302 research outputs found
Park Cool Island Examinations in Debrecen, Hungary
Urban heat island (UHI) intensities are lower in urban green spaces than in their urbanized neighborhood. The phenomenon is called Park Cool Island (PCI). PCI intensities can be determined on the base of thermal differences between city centers and parks. Characteristics of the green spaces determine the degree and temporal dynamics of the thermal differences between the green areas and the built-up surfaces in the settlements. Results of a one year long UHI and PCI measurement campaign are presented here. 32 measurements were carried out using mobile techniques under different synoptic conditions in the time of the maximal development of UHI and PCI in the town of Debrecen (population cca. 220 000) in East Hungary.
Beside the UHI, existence of the park cool island has been proved in Debrecen. Characteristic maximal UHI intensities have been determined for typical built-up types. The impacts of urban green spaces on the temporal and spatial dynamics of the development of the UHI and PCI were determined. Annual and seasonal mean maximal PCI intensities were calculated for Debrecen. Impacts of synoptic conditions on the development of PCI were taken into account as well. Cooling effects of the parks was traced in their urban environment
A multivariate linear regression model of mean maximum urban heat island: a case study of BeregszĂĄsz (Berehove), Ukraine
The aim of the research presented in this study is to elaborate a multivariate linear regression model that describes the spatial structure of the mean maximal development urban heat island (UHI) formed under favorable synoptic conditions on the basis of surface parameters. Temperature data were gathered in a small town, Beregszåsz, Zakarpattia, Ukraine. As a first step, a one-year-long UHI measurement campaign has been carried out using mobile techniques in order to obtain data for the description of the UHI in the study area. Two surface parameters (ratio of non-evaporating surfaces in the environment of the measurement sites and distance of measurement sites from the center of the settlement) have been selected first. The two surface parameters had to be quantified next. On this basis, relationships between surface parameters as independent variables and UHI intensities as dependent variables could be traced by performing a multivariate linear regression. Results have showed that the two chosen parameters have strong impact on UHI development in our study area. Spatial structure and intensity of UHI can be estimated with an accuracy of 0.4 °C within the built-up area of the town using our MLR model. The high resolution surface parameter database and the UHI estimating model enable the prediction of heat load of smaller spaces and town parts. This procedure helps the reduction of heat load and the determination of the location of green areas important for urban planning as well
Impacts of Some Surface Parameters on Urban Heat Island Development
Effects of two important surface parameters (distance from the center of the settlement and extent of evaporating surfaces) on development of urban heat island (UHI) are examined in the present paper. The study area is the town of BeregszĂĄsz (Transcarpathia, Ukraine) with a population of 26 000. Mobile temperature measurements were carried to out in order to gain information on the characteristics of the UHI in ten day intervals in two one year long campaigns in 2005 and 2008. The main purpose was to determine the urban thermal excess in the different parts of a relatively small town, and to elaborate an empirical model equation of the development of UHI in the different parts of the town affected by horizontal surface conditions
The development of the urban heat island studied on temperature profiles in Debrecen
The development of the urban heat island (UHI) was studied in Debrecen, Hungary using temperature
profiles. Mobile temperature measurements were carried along a cross section of the city. The route crossed the
typical built up units of the city. The seasonal characteristics of the profile were determined. It was found that in
the non-heating season stronger and more regular profiles formed. The measurements provided information on the
temporal changes of the mean heat island intensities. A special feature is the occurrence of a secondary minimum
and a maximum on the profile. In the inner parts of the city the profiles are similar only the amplitudes of the
intensities are different, while in the peripheral sectors quite flat profiles were found
Effects of the synoptic conditions in the development of the urban heat island in Debrecen, Hungary
In this paper the results of the examinations on the effects of various weather conditions on the
development and spatial pattern of the urban heat island (UHI) in Debrecen, Hungary are presented. Measurements
were carried out using mobile technique with instruments that were mounted on cars. Examinations proved the
existence of the UHI in Debrecen. Under favorable weather conditions (anticyclone activity, calm weather) the heat
island showed some unique spatial characteristics. Most regular heat islands developed in cases when Hungary was
situated between weak high and low pressure systems. Under antycyclonic conditions strong heat islands formed, but
their shape was usually deformed by the prevailing winds. Strong cyclone activity eliminated the formation of the
UHI, while under weak cyclone activity regular, but weak heat islands of only about 1°C developed
Anthropogeomorphologic impacts of onshore and offshore windfarms
ĂsszefoglalĂĄs - A szĂ©lerĆmƱvek Ă©pĂtĂ©se sorĂĄn kisebb-nagyobb mĂ©rtĂ©kben ĂĄtalakĂtjuk a berendezĂ©s közvetlen környezetĂ©t.
A mestersĂ©gesen lĂ©trehozott formĂĄk Ă©s az esetlegesen kivĂĄltott folyamatok azonban a telepĂtĂ©s helyszĂnĂ©-
tĆl fĂŒggĆen kĂŒlönbözĆek lesznek. Az onshore szĂ©lparkok lĂ©tesĂtĂ©se több Ă©vtizedes mĂșltra tekint vissza. Nagy kö-
rĂŒltekintĂ©ssel, a lehetĆ legkisebb környezeti beavatkozĂĄssal vĂ©gzett telepĂtĂ©sek antropogeomorfolĂłgiai hatĂĄsai elhanyagolhatĂłk.
A szĂ©lenergia hasznosĂtĂĄs mĂĄsik, egyre jelentĆsebb szerepet betöltĆ helyszĂnei a selfterĂŒletek lesznek.
Az offshore telepĂtĂ©si körĂŒlmĂ©nyek termĂ©szetesen kĂŒlönböznek a szĂĄrazföldön tapasztaltaktĂłl. A tengeri szĂ©lparkok
környezetre gyakorolt hatĂĄsairĂłl mĂ© g kevĂ©s informĂĄeióåll rendelkezĂ©sre, hiszen ezek telepĂtĂ©se a közelmĂșltban
indult meg. A tanulmĂĄnyban felvetett kĂ©rdĂ©sek idĆszerƱek, mert a következĆ Ă©vtizedekben az offshore
parkok jelentĆs növekedĂ©s e vĂĄrhatĂł.
Summary - During the establishment of wind farms their close environment can become more or less altered.
Artificial forms and processes triggered by the construction and operation of wind turbines can be different
depending on the site. There is a several decades-long history of the operation of onshore wind farms, so many
studies have dealt with their effects on landscape evolution. Anthropogeomorphologic issues of well-planned and
appropriately carried out projects are insignificant. Continental shelf areas are sites with increasing importance for
the establishment of wind farms today. The conditions for offshore projects are different from those of continental
ones. There is not much information on the environmental effects of offshore wind farms, since their establishment
has begun just recently. Questions raised in this paper have a growing importance together with the growing
investments in this field
Heavy metal loads in the soil of Debrecen
Results of examinations on the amount, and spatial distribution of heavy metal compounds in the soilof Debrecen, their geographic, pedologic and ecologic aspects are presented in this study. The effectsof the differences in traffic conditions, build-up/land use and the density of vegetation on the heavymetal content of the soils have been examined in city of Debrecen and its closer environment.Cadmium-, cobalt-, nickel-, lead-, and copper-contents of the soil samples taken from 88 sites of thesample area have been studied after acidic extraction, using atomic absorption spectrometer with theflame technique. Close-to-background concentrations of heavy metals in unpolluted soils of theforested area of the NagyerdĆ were determined. Spatial differences in the heavy metal content of thesoils for the whole area of Debrecen have been studied. Influence of soil properties (humus, CalciumCarbonate content, pH and grain-size distribution) on the binding and mobility of heavy metals in thesoil has been examined. Vertical distribution and mobility of heavy metal compounds in acid sandysoils was determined. Heavy metal content of soil in the most sensitive areas, playgrounds,recreational areas, urban gardens and grazing fields along busy roads has been surveyed
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