Synoptic Conditions Generating Heat Waves and Warm Spells in Romania

Abstract

Abstract:Heat waves and warm spells are extreme meteorological events that generate a significant number of casualties in temperate regions, as well as outside of temperate regions. For the purpose of this paper, heat waves and warm spells were identified based on daily maximum temperatures recorded at 27 weather stations located in Romania over a 55-year period . The intensity threshold was the 90th percentile, and the length of an event was of minimum three consecutive days. We analyzed 111 heat wave and warm spell events totaling 423 days. The classification of synoptic conditions was based on daily reanalysis at three geopotential levels and on the online version of a backward trajectories model. The main findings are that there are two major types of genetic conditions. These were identified as: (i) radiative heat waves and warm spells (type A) generated by warming the air mass due to high amounts of radiation which was found dominant in warm season; and (ii) advective heat waves and warm spells (type B) generated mainly by warm air mass advection which prevails in winter and transition seasons. These major types consist of two and three sub-types, respectively. The results could become a useful tool for weather forecasters in order to better predict the occurrence of heat waves and warm spells.

Refining the Spatial Scale for Maize Crop Agro-Climatological Suitability Conditions in a Region with Complex Topography towards a Smart and Sustainable Agriculture. Case Study: Central Romania (Cluj County)

“…Datasets are freely available on the World Data Center PANGAEA portal. ROCADA derived data have the best spatial resolution and accuracy when compared to other available gridded databases at present, such as E-OBS, CarpatClim [53], or Agri4Cast Resources Portal.…”

Tropospheric Dust and Associated Atmospheric Circulations over the Mediterranean Region with Focus on Romania’s Territory

“…This type of synoptic pattern at a continental scale usually generates heat waves over South and South-Eastern Europe, including the territory of Romania. The associated atmospheric circulation can transport dust particles from Libya at surface level, as well as from Northern Africa up to 1500 and 5000 m altitude [45]. In order for this to take place, there must be a strong pressure gradient over the dust particles source region.…”

Future changes in five extreme precipitation indices in the lowlands of Romania

“…Usually, during the first future period, a decrease is expected, whereas during the last ones, the values do not indicate a similar pattern for all regions. Therefore, if the trend detected over the historical period (Croitoru et al ., ) will continue, this trend could be a consequence of the fact that those areas are the most prone to dryness and drought events due to their exposure to a higher frequency of warm and dry air masses (Sfîcă et al ., ).…”

“…Furthermore, extreme precipitation events prove to have significant social and economic impacts, especially in developing countries, and cause serious damage to settlements, transportation, and agriculture (Аlexandrov et al, 2006;Bogdan and Marinic a, 2007;Nandintsetseg et al, 2007;Toreti and Desiato, 2008;Choi et al, 2009;Wang et al, 2012;Croitoru et al, 2016;Croitoru et al, 2018). One of the most important direct consequences can be observed in the case of natural vegetation and ecosystems (IPCC, 2014), while indirect impacts are specific to agriculture (Capra et al, 2013;Patel and Shete, 2015;Stagge et al, 2015;Nugroho and Nuraini, 2016), water supply and management (Estrela and Vargas, 2012;Stagge et al, 2015;Hui-Mean et al, 2018), and human welfare (WHO Regional Office for Europe, 2007;Smith et al, 2014;Mishra et al, 2015).…”