No abstract

The paper presents the main features of the urban heat island of Galați city during the summer season for a period of 16 years (2003-2018) using MODIS products. The main objectives were to analyse the extension and geometry of the urban heat island (UHI), its intensity, as well as its connection with land cover. The study is based on LST (Land Surface Temperature), a product obtained from Moderate Resolution Imaging Spectroradiometer (MODIS) sensors located on board of the Terra (EOS AM-1) satellite since 2001 and Aqua (EOS PM-1) satellite since 2003. The boundaries, geometry and spatial extent of the UHI were delimited primarily through the Rodionov test. Through this method, the changing points along four transects over Galați city were identified (North-South, East-West, Northeast-Southwest and Northwest-Southeast) and have been used to delimitate the UHI. Overall, the Galați UHI assessed by satellite information is stronger during the day when the UHI is split in two centres, developed over the industrial area in the west and over the residential part of the town in the east, while during the night the UHI is weaker being developed more clearly over the oldest part of the city. One of the major characteristics of the Galați UHI is that it is highly influenced by the water bodies encircling the city. During the day the intensity of UHI reaches 2-2.5°C while during the night decreases below 2.0°C. The relation of the UHI with land cover and the attenuation of UHI in the surrounding area are also investigated.

ABSTRACT:In the present paper we have analysed the synoptic conditions generating the maximum amount of precipitation within 24 hours in Romania. This study is based on the analysis of daily weather maps from different archived sources and also on the processing of ROCADA data set concerning the daily amount of precipitation in Romania (1961Romania ( -2013. Some main weather types (WTs) -specific for the occurrence of high amount of precipitation in Romania -were established, and the daily recording of the maximum amount of precipitation for 24 hours at monthly level was assigned to one of the defined WTs. Out of the total of 312 days analysed from the synoptic point of view, a total of 133 days (42.6%) were characterized by high atmospheric instability. The larger part of them (100 days) were determined by cold air advections associated to long-wave troughs propagating from North Atlantic towards the centre of European continent, while the rest of 33 days were generated by cut-off lows identified in the middle and upper troposphere in South-East Europe. As well, 124 days (39.7%) were assigned to Mediterranean cyclones transiting the region of Romania and 55 days (17.7%) were associated with Atlantic cyclones activity. The climatology of each synoptic type is presented. Also, regional and seasonal disparities are described using proper interpolation methods.

The study analyses the spatial and temporal changes occurred in the builtup area of Iași city and its surrounding areas using cartographic materials from different time periods. The paper aims to highlight the areas where the most significant changes took place by identifying the main evolution patterns, generated by certain natural or human-driven factors. The results of the study were achieved by using specific photo-interpretation methods of the available orthophotomaps form 2006 and 2012, mainly using the professional GIS softwares TNT Mips 7.2., ArcGIS 10.2 and Global Mapper 11. The changes have lead on the one hand to the conversion of the former industrial areas and thus, the urban regeneration, but also to the periurbanization phenomenon, with major functional and structural effects.