Forest fires causes and motivations are poorly understood in southern and south-eastern Europe. This research aims to identify how experts perceive the different causes of forest fires as defined in the classification proposed by the European Commission in 2013. A panel of experts (N = 271) was gathered from the EU Southern Member States (France, Greece, Italy, Portugal, and Spain) and from Central (Switzerland) and south-eastern Europe (Croatia, Serbia, Bosnia and Herzegovina, Republic of North Macedonia, and Turkey). Experts were asked to answer a questionnaire to score the importance of the 29 fire causes using a five point (1–5) Likert Scale. Agricultural burnings received the highest score, followed by Deliberate fire for profit, and Vegetation management. Most of the events stem from Negligence, whereas malicious fire setting is arguably overestimated although there are differences among the countries. This research demonstrates the importance of different techniques to enhance the knowledge of the causes of the complex anthropogenic phenomenon of forest fire occurrence.

Forest fires that occurred in Portugal on June 18, 2017, caused several tens of human casualties. The cause of their emergence, as well as many others that occurred in western Europe at the same time remained unknown. Taking into account consequences, including loss of human lives and endangerment of ecosystem sustainability, discovering of the forest fires causes is the very significant question. The heliocentric hypothesis has indirectly been tested, according to which charged particles are a possible cause of forest fires. We must point out that it was not possible to verify whether in this specific case the particles by reaching the ground and burning the plant mass create the initial phase of the formation of the flame. Therefore, we have tried to determine whether during the critical period, i. e. from June 15-19 there is a certain statistical connection between certain parameters of the solar wind and meteorological elements. Based on the hourly values of the charged particles flow, a correlation analysis was performed with hourly values of individual meteorological elements including time lag at Monte Real station. The application of the Adaptive Neuro Fuzzy Inference System models has shown that there is a high degree of connection between the flow of protons and the analyzed meteorological elements in Portugal. However, further verification of this hypothesis requires further laboratory testing.

In this research we search for a functional dependence between the occurrence of forest fires in the USA and the factors which characterize the solar activity. For this purpose we used several methods (R/S analysis, Hurst index) to establish potential links between the influx of some parameters from the sun and the occurrence of forest fires with lag of several days. We found evidence for a connection and developed a prognostic scenario based on the Adaptive neuro-fuzzy interference system (ANFIS) technique. This scenario allows the prediction between 79-93% of forest fires.

The research included trends in water temperature of the Danube River at Bogojevo gauge and surface air temperature at the nearby meteorological station Sombor, as well as an analysis of the results obtained in relation to the claims of the existence of the hiatus in global air temperature increase in the period 1998-2012. In the period 1961-2013, there was a statistically significant increase in the mean annual water temperature (0.039?C/year), as well as all the average monthly values. However, with annual values for the period 1998-2013, there was a decrease. The longest periods of negative trend (27 years) were recorded for January and February. A high correlation was found between the surface air temperature and water temperature for all monthly and seasonal values. In the mean annual air temperature the presence of the hiatus is not observed, but a negative trend is recorded in March (32 years), December (43 years) and February (49 years). The highest correlations between water temperature and North Atlantic Oscillation (NAO), Arctic Oscillation (AO) and Atlantic Multidecadal Oscillation (AMO) were obtained for the NAO in January (0.60), the AMO in autumn (0.52) and the NAO in winter (0.51). For surface air temperature, the highest correlations were registered for the AMO in summer (0.49) and the NAO in winter (0.42). The results indicate the dominant role of natural factors in the decrease of winter air temperature and water temperature of the Danube.