Synoptic and dynamical characteristics of high-impact storms affecting the Iberian Peninsula during the 2018–2021 extended winters

In the extended winters from December 2017 to April 2021, numerous high-impact storms affected the Iberian Peninsula (IP) with heavy precipitation and/or strong winds. Here, we provide a comprehensive assessment of these events, synoptic conditions, large-scale dynamics associated with storms, and a climatological analysis to improve public awareness and natural disaster prevention. Variability analysis presents that their maximum intensity ranges from 955 hPa to 985 hPa, a two-to-four-day lifetime, and the highest frequency (eight events) occurred in January. At the instant of maximum intensity, anomalies presented low MSLP values (−21.6 hPa), high values of water vapor (327.6 kg m−1s−1) and wind speed at 250 hPa (29.6 m s−1), high values of θe at 850 hPa (19.1 °C), SST (−1 °C), and QE (−150 W m−2), near Iberia. The values obtained during the storm impact days exceeded the 98th percentile values in a high percentage of days for daily accumulated precipitation (34%), instantaneous wind gusts (46%), wind speed at 10 m (47%), and concurrent events of wind/instantaneous wind gusts and precipitation (26% and 29%, respectively). These results allow us to characterize their meteorological impacts on the IP, namely those caused by heavy precipitation and wind.Fundação para a Ciência e a Tecnologia | Ref. UID/GEO/50019/2019Fundação para a Ciência e a Tecnologia | Ref. PTDC/CTAMET/29233/2017Fundação para a Ciência e a Tecnologia | Ref. LISBOA-01-0145-FEDER-029233Fundação para a Ciência e a Tecnologia | Ref. NORTE-01-0145-FEDER-029233Fundação para a Ciência e a Tecnologia | Ref. 2021.04927.BDXunta de Galicia | Ref. ED431C 2021/4

Disruption risk analysis of the overhead power lines in Portugal

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGThe growing increase in frequency and intensity of extreme weather events (EWEs) has a wide impact on energy systems and consumers, as energy transmission infrastructures - overhead power lines (OPL). The main objective of this work is to present the methodology of risk analysis of the EWEs on OPL in Portugal. The level of risk associated with each of the identified events is classified according to the probability of occurrence and consequences, in a risk matrix, and through the cause-and-effect analysis. It is concluded that, in Portugal, the extreme wind – corresponding to level 11 of the Beaufort Wind Force Scale, that is, values equal to or higher than 105.1 km h- 1 (29.22 m s-1) – is the main factor that provoked the OPL disruption, between 28% and 40% of analyzed events associated with windstorms. Considering the occurrence of compound events - wind and rain - the probability of damage to OPL is between 21% and 30%; for wind and ice, it is 3%–5%. EWEs represent a serious risk for electrical systems, and it is necessary to develop effective solutions to minimize the associated impacts, such as the modification and upgrade of the current design and engineering standards, and electrical network monitoring.Fundação para a Ciência e a Tecnologia | Ref. UID/GEO/50019/2019Fundação para a Ciência e a Tecnologia | Ref. PTDC/CTAMET/29233/2017Fundação para a Ciência e a Tecnologia | Ref. LISBOA-01-0145-FEDER-029233Fundação para a Ciência e a Tecnologia | Ref. NORTE-01-0145- FEDER-029233Fundação para a Ciência e a Tecnologia | Ref. UIDB/04033/2020Fundação para a Ciência e a Tecnologia | Ref. 2021.04927.BDXunta de Galicia | Ref. ED431C 2021/4