Rainfall-Induced Landslides and Erosion Processes in the Road Network of the Jaén Province (Southern Spain)

Abstract

Rainfall thresholds are one of the most widely applied methods for indirectly estimating landslide return periods, which are subsequently used in hazard analyses. In this study, the starting point is an incidence database of landslides and erosive processes affecting the road network of the province of Jaén (southern Spain), in which the positions and dates of civil repair works can be found. Meanwhile, the use of a daily rainfall database in a dense grid (1 km) allowed for the estimation of the rainfall series at each incidence point with high precision. Considering the news in the local media and applying spatial proximity, temporal proximity, and maximum return period criteria, rainfall events of various duration (1 to 90 days) could be associated approximately with each point. Then, the rainfall thresholds and their return periods were estimated. A linear equation was adjusted for the rainfall duration threshold (E = 6.408 D + 74.829), and a power-law curve was adjusted for the intensity–duration pair (I = 47.961 D−0.458). Non-significant differences were observed between the thresholds and the return periods for the lower and higher magnitude incidences, but the durations for the former were lower (1–13 days), compared to those of the latter (7–22 days). From the equations, rainfall events of different durations could be estimated for use in hazard analysis, as well as for the future development of warning systems.

Methodology for Determining Gully Widths in Multi-Temporal Studies in Olive Groves of Southern Spain

“…They found the highest peak for monthly rainfall in December 2010 for the period 1980-2017. Moreover, the study of [32] revealed that the mean annual rainfall in 2010 (1069 mm) doubled the historical mean annual precipitation range for the period 1970-2000 (500-600 mm).…”

Monitoring instabilities by MT-InSAR in a mesa placed town (Arjona, Guadalquivir valley, South Spain)

“…They occurred after 2015, a period particularly dry in the region. Recent studies (Carpena et al, 2021) show that landslides and erosion in the Upper Guadalquivir are associated with recurrent wet periods that include rainfall events with a return period between 5 to 20 years. Thus, in the next foreseeable rainy event, it can be expected that the velocity of movement in the observed sectors will increase dramatically, producing even catastrophic episodes.…”

“…The town of Arjona, in the Upper Guadalquivir valley, is a good example of this topographic-urbanistic setup and is subject to slope movements due to its singular topographic and geological features. Most of the slope movements in the region are related to highly rainy events that show a return period greater than 10-20 years (Carpena et al, 2021). In these events, landslides can be exhaustively followed by photogrammetry and LiDAR techniques , or by UAV surveys (Fernández et al, 2016).…”