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The aim of our study is to analyse the spatial patterns and temporal trends of average and extreme precipitation events in a few selected plain regions between 1951 and 2019. Besides the Great Hungarian Plain we chose two plain regions located in the southern part of the continent (i.e. the Po Valley and the Romanian Plain) with the purpose of comparing similar geographical regions, and creating a scientific basis to comprehensively analyse the effects of climate change on economy, society, and nature. For choosing the plains, objective criteria were used, namely, (i) the elevation remains under 200 m throughout the defined area, and (ii) the difference between the neighbouring grid points within the plain region does not exceed 50 m. The analysis of extreme precipitation events was performed for annual periods by calculating 17 climate indices. Based on our research of the past, there is a clear increase in the frequency and intensity of extreme precipitation events, in the length of dry periods as well as in the occurrence of extreme weather events.

The aim of this study is to analyse the thermal properties of natural and artificial urban surfaces and the impact of surface colours and shading. Measuring campaigns were conducted in spring and summer (2018-2019) in the district XI of Budapest to determine the surface temperature of various urban materials. The results show that the coolest surfaces are natural covers (water, vegetation), while the hottest surfaces are concrete pavements, asphalt and rubber paving when exposed to direct solar radiation. Moreover, among concrete pavements, light coloured surfaces warm up 5-6 °C less on average compared to dark coloured surfaces. The use of rubber paving may be disadvantageous from the urban climatological point of view, as these surfaces become extremely hot under sunny conditions.

The ratio of buildings, streets, and other artificially covered areas are increasing in cities. Ferencváros is an inner district of Budapest, the capital city of Hungary. For the local government of the district it is an important goal in the framework of the urban development planning to increase the proportion of vegetation since green areas have a mitigating effect for the urban heat island (UHI) intensity. We carried out an in situ measurement program for air temperature and relative humidity with 24 measuring points in Ferencváros, and also completed a green area survey in the renovated part of the district. The main aim of this paper is to analyse the daily cycle and the spatial structure of the UHI intensity based on air temperature.

Precipitation is the major atmospheric source of surface water, thus, in order to build appropriate adaptation strategies for various economic sections related to water resources it is essential to provide projections for precipitation tendencies as exact as possible. Extreme precipitation events are especially important from this point of view since they may result in different environmental, economical, and/or even human health damages. Excessive precipitation for instance may induce floods, flash-floods, landslides, traffic accidents. On the other hand, lack of precipitation is not favorable either: long dry periods affect agricultural production quite negatively, and hence, food safety can be threatened. Several precipitation-related indices (i.e., describing drought or intensity, exceeding different percentile-based or absolute threshold values) are analyzed for the Carpathian region for 1961–2100. For this purpose 11 completed regional climate model simulations are used from the ENSEMBLES database. Before the thorough analysis, a percentile-based bias correction method was applied to the raw data, for which the homogenized daily gridded CarpatClim database (1961–2010) served as a reference. Absolute and relative seasonal mean changes of climate indices are calculated for two future time periods (2021–2050 and 2071–2100) and for three subregions within the entire Carpathian region, namely, for Slovakia, Hungary and Romania. According to our results, longer dry periods are estimated for the summer season, mainly in the southern parts of the domain, while precipitation intensity is likely to increase. Heavy precipitation days and high percentile values are projected to increase, especially, in winter and autumn.