Riesgo de heladas por inversión térmica e incidencia agrícola en la Demarcación Hidrográfica del Segura (DHS)

Abstract

The interior southeast of the Iberian Peninsula is recurrence affected by winter anticyclonic situations, in many cases fueled by continental polar / arctic air advections. Under these conditions, intrabetic basins and valleys are prone to the development of nocturnal temperature inversion processes (ITN), assuming a notable influence throughout the year. A clear example is constituted by the interior valleys of western sectors of the Region of Murcia, east of Jaén, south of Albacete or north of Almeria, especially when the nocturnal cooling of the soil appears accompanied by subsident anticyclonic air movements, cold advections of a northern component. at low atmospheric levels, and cold catabatic flows from the main mountain systems of the DHS. Frosts in these sectors are abundant, especially in winter. In this research, the characteristics and factors that trigger the situations of nocturnal temperature inversion are analyzed, and the notable thermal differences that they generate between valley zones and orographically complex areas, with the use of climatic data associated with observatories and meteorological stations, to its own network of recording thermometers (datalogger), atmospheric soundings carried out in the study area, in particular those related to the temperature regime, vertical thermal stratification and indicators of atmospheric stability, and the use of satellite images. The regularity of nocturnal inversion processes throughout the year, especially in winter, is one of the main causes for the appearance of a large number of frosts in inland valleys. Throughout the Doctoral Thesis, the spatio-temporal trend of various climatic indices associated with minimum temperatures is analyzed, where a clear thermal rise and a significant reduction in frost days during the last decades is highlighted. Finally, as a complement to the analysis of physical factors, an in-depth study of agricultural land uses and their interaction with the effects generated by frost on the main groups of crops in the study area is carried out, with the elaboration of risk mapping og high resolution. Key words: inversion, subsidence, advection, catabatic, frost, stability.