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Flood model for the Bódva catchment
12-26Views:160In term of floods the current area of Hungary has extensively been endangered. Modelling of flood processes – mainly following the hydrological events in the riverbed – has recently been developed. As far as protection dykes provide protection of the inhabited and agricultural areas, the flood models can run with acceptable preciseness. However, when dykes cannot withstand against the increasing load and a dyke burst occurs, fast and efficient protection measures shall be taken in the protected areas. The dynamic 4D Flood model presented in this paper makes possible a fast modelling of dyke burst occurring in the protected side and spreading of water mass, based on real parameters. For this reason the features of protected area shall be recognised, for example topology of creeks, features of agricultural and inhabited areas, parameters of roads, railways, rainwater drainage, buildings, natural conditions (soil parameters, meteorological characteristics, etc.). The results satisfy the comprehensive demands of the Directorate General for Disaster Prevention of Borsod-Abaúj-Zemplén County. In case of dyke burst, the completed Flood Model can run the expected events of the next hour in a few minutes. This time is enough for the specialists to bring operative decisions to protect the inhabitants and avoid material losses.
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Assessment of spatio-temporal waterline changes of a reservoir: A case study of Ujjani wetland, Maharashtra, India
1-13Views:0The Ujjani reservoir is an artificial inland wetland and a potential Ramsar site in Maharashtra, India. The present study investigates the changes in the surface water area over time using remote sensing imageries (LANDSAT, LISS-III, Sentinel 2 series) for four decades (1981 to 2021) and the normalized difference water index (NDWI). The study reveals that the overall mean amount and rate of decrease in the surface water area are estimated at 20.50% (44.31 + 30.38 km2) and 0.75% year-1 (1.62 + 1.36 km2year-1), respectively. Furthermore, multiple correlation matrix analysis shows a strong positive correlation between surface water area and rainfall while a weak negative correlation with mean annual temperature (TMAX). Thus, indicating rainfall as the principal factor in inducing changes to the surface water area of the Ujjani wetland. However, the study also finds that the impact of the dramatic rise in population growth and anthropogenic activities in the form of overexploitation and land encroachments for agriculture are gradual but significant cursors to wetland degradation. Hence, the study recommends periodic monitoring, management, and conservation of wetlands, by employing stringent policies and effective technological measures.
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Relation of meteorological elements and air pollutants to respiratory diseases
1-15Views:48This paper determines the characteristic weather types over the Carpathian Basin for the summer – early autumn period (July 15 – October 15) and the winter months (December, January, and February), with the levels of chemical (CO, NO, NO2 , NO2/NO, O3, O3max, SO2, PM10) and biological [Ambrosia (ragweed) pollen] air pollutants, and with their effect to the respiratory diseases. Based on the ECMWF data set, daily sea-level pressure fields analysed at 00 UTC (Coordinated Universal Time) were prepared for each weather type (cluster) in order to detect the relation between, on the one hand, the sea-level pressure patterns and, on the other, the levels of the chemical and biological air pollutants as well as the frequency of the respiratory diseases in Szeged. Objective definition of the characteristic weather types occurred by using the methods of Factor Analysis and Cluster Analysis. As a result, in the summer – early autumn period the total patient number is proportional to the mean monthly temperature, the maximum and minimum temperatures; however, respiratory diseases occur more frequently, when relative humidity is low. On the other hand, in the winter months there is no relation between the meteorological variables and the patient numbers.
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Climate as a risk factor for tourism
113-125Views:148Weather and climate risk factors for tourism are surveyed and illustrated with regard to the expected climate changes in Hungary. These changes are not at all advantageous and which affect the business in question both directly and indirectly. These are the summer resort tourism (characterised by bioclimatic indices). Green tourism is the next one to characterise, including skiing, mountain climbing and eco-tourism, as well. Here both day-to-day weather extremes and long-lasting effects on the biota (e.g. drought, or inundation for plain-area eco-tourism). Last, but not least the urban (cultural- and shopping-) tourism is presented, since the large towns exhibit their special climate and different risks. The paper intends to specify these meteorological factors and effects also in terms of the different types of touristic activities. The general statements on the effect of weather and climate on tourism are illustrated by a few individual parameters and also by the so called Physiologically Equivalent Temperature. Annual and diurnal course of this parameter are presented, together with various trends in this variable at different sites and in different (hot and cold) extremities of the occurring values. Other examples, helping the tourism industry are presented in various climate conditions of the country. They include high precipitation and high relative humidity information. The paper also lists the possible adaptation measures to extreme events and also their likely changes in time.