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Extreme precipitation events (EPEs) present potentially an enormous societal risk and often lead to major human and economic impacts. In the mid-latitudes, such EPEs are often triggered by intense extratropical cyclones and their associated frontal systems. Over the last decade, several studies have shown the important and specific role played by Atmospheric Rivers (ARs) in the occurrence of EPEs in western Europe, particularly in the Iberia Peninsula. In this study we analyze the all-time 24 h record-breaking precipitation (120.3 mm) recorded in the historical Dom Luiz Observatory (since 1863) in Lisbon, Portugal, between 12 and 13 December 2022. A synoptic evaluation of surface and upper-level fields from 5 to 14 December is performed using ERA-5 reanalysis. The week before the EPE, there was a combined effect of a large-scale SLP gradient resembling the NAO negative phase, a southerly position of the jet stream and an above normal positive SST anomalies over the North Atlantic leading to the development of several low-pressure systems at relatively low latitudes, all travelling along the same mean path towards western Europe. The atmospheric river associated with this event was first detected on late 10 December associated with a deep extratropical cyclone. The combination of high Integrated Vapor Transport (and moisture inflow by the warm conveyor belt), with a dynamical component characterized by a suitable uplift motion, allowed the system to evolve and maintain its AR characteristics for 72 h. The extratropical cyclone and associated AR moved northeast towards Iberia, making landfall in Portugal, on 12 December, as an extreme AR event, leading to the 24 h precipitation record breaking event. [ABSTRACT FROM AUTHOR]

The floods that struck the lower Tagus valley in February 1979 correspond to the most intense floods in this river and affected the largest number of people in a river flow event in Portugal during the last 150 years. In fact, the vast area affected significantly impacted circa 10 000 people in the lower Tagus sector (and an additional 7000 in other regions of Portugal), including thousands of people evacuated or made homeless. In this context, the present study focuses on an in-depth analysis of this event from a hydrodynamic perspective by means of the Iber+ numerical model and on developing strategies to mitigate the flood episodes that occur in the lower section of the Tagus River using the exceptional floods of February 1979 as a benchmark. In this sense, dam operating strategies were developed and analyzed for the most important dam along the Tagus River basin in order to propose effective procedures to take advantage of these infrastructures to minimize the effect of floods. Overall, the numerical results indicate a good agreement with watermarks and some descriptions of the 1979 flood event, which demonstrates the model capability to evaluate floods in the area under study. Regarding flood mitigation, results obtained indicate that the frequency of floods can be reduced with the proposed strategies, which were focused on providing optimal dam operating rules to mitigate flooding in the lower Tagus valley. In addition, hydraulic simulations corroborated an important decrease in water depth and velocity for the most extreme flood events, and also a certain reduction in the flood extension was detected. This confirms the effectiveness of the proposed strategies to help in reducing the flood impact in the lower Tagus valley through the efficient functioning of dams. [ABSTRACT FROM AUTHOR]

Landslides are complex phenomena that cause important impacts in vulnerable areas, including the destruction of infrastructure, environmental damage, and loss of life. The occurrence of landslide events is often triggered by rainfall episodes, single and intense ones or multiple occurring in sequence, i.e. clustered in time. Landslide prediction is typically obtained via process-based or empirical thresholds. Here, we develop a new approach that uses information on the temporal clustering of rainfall to detect landslide events and compare it with the use of classical empirical rainfall thresholds. In addition, we evaluate the performances of the two approaches combined together as a case study in the region of Lisbon in Portugal. We consider a dataset that categorises landslides into shallow and deep events, and a review of empirical rainfall thresholds that makes a good benchmark for testing our novel method. We show that the new approach based on temporal clustering overall has a good power of detecting landslide events, but has a skill comparable with the classic rainfall threshold method. While there is no clear outperformance of one method, the novel clustering-based method has a higher sensitivity despite a lower precision than the threshold-based method. For all approaches, the potential detection is better for deep landslides than for shallow ones. The results of this study could help to improve the prediction of rainfall-triggered landslides. [ABSTRACT FROM AUTHOR]

The floods that struck lower Tagus valley in February 1979 correspond to the most intense floods in this river and affected the largest number of people in a river flow event in Portugal, during the last 150 years. In fact, the vast area affected impacted significantly circa 10k people in the lower Tagus sector (and an additional 7k in other regions of Portugal), including thousands of people evacuated or made homeless. In this context, the present study focuses on an in depth analysis of this event from a hydrodynamic perspective by means of Iber+ numerical model and on developing strategies to mitigate the flood episodes that occur in the lower section of the Tagus river using the outstating floods of February 1979 as benchmark. In this sense, several large dams and reservoirs are located along the Tagus river basin, and for that, dam operating strategies were developed and analyzed to take advantage of these infrastructures to minimize the effect of floods. Overall, the numerical results indicate a good agreement with water marks and some descriptions of the 1979 flood event, which demonstrates the model capability to evaluate floods in the area under study. Regarding flood mitigation, obtained results indicate that the frequency of floods can be reduced with the proposed strategies. In addition, hydraulic simulations corroborated an important decrease in water depth and velocity for the most extreme flood events, and also a certain reduction of flood extension was detected. This confirms the effectiveness of the proposed strategies to help in reducing flood impact in lower Tagus valley through the efficient functioning of dams. [ABSTRACT FROM AUTHOR]

Rainfall is considered the most important physical process for landslide triggering in Portugal. It is expected that changes in the precipitation regimes in the region, as a direct consequence of climate change, will have influence in the occurrence of extreme rainfall events that will be more frequently, throughout the century. The aim of this study relied on the assessment of the projected future changes in the extreme precipitation over Portugal mainland and quantifying the correlation between extreme rainfall events and landslide events through Rainfall Triggering Thresholds (RTTs). This methodology was applied for two specific locations within two Portuguese areas of great geomorphological interest. To analyze the past frequency of landslide events, we resorted to the DISASTER database. To evaluate the possible projected changes in the extreme precipitation, we used the Iberia02 dataset and the EURO-CORDEX models' runs at a 0.11° spatial resolution. It was analyzed the models' performance to simulate extreme values in the precipitation series. The simulated precipitation relied on RCM-GCM models' runs, from EURO-CORDEX, and a multimodel ensemble mean. The extreme precipitation assessment relied on the values associated to the highest percentiles, and to the values associated to the RTTs' percentiles. To evaluate the possible future changes of the precipitation series, both at the most representative percentiles and RTTs' percentiles, a comparison was made between the simulated values from EURO-CORDEX historical runs (1971–2000) and the simulated values from EURO-CORDEX future runs (2071–2100), considering two concentration scenarios: RCP 4.5 and RCP 8.5. In the models' performance, the multimodel ensemble mean appeared to be within the best representing models. As for the projected changes in the extreme precipitation for the end of the century, when following the RCP 4.5 scenario, most models projected an increase in the extreme values, whereas, when following the RCP 8.5 scenario, most models projected a decrease in the extreme values. [ABSTRACT FROM AUTHOR]

After World War I, cinema emerged as a powerful instrument of (counter) information for the colonial cause in the service of the European colonial powers, and Portugal was no exception. In fact, the use of cinema by the Portuguese authorities for colonial propaganda is the subject of this article. The aim of this study is to show how the post-war "winds of change" shifted the paradigm of the Portuguese colonial cinema by comparing the representation of Luanda in two colonial films about Angola produced in the 1950s and 1970s: Luanda, Cidade Feiticeira, (1950) and Luanda e a sua Gente (1973), respectively. [ABSTRACT FROM AUTHOR]

Precipitation extremes in mainland Portugal (south-western Europe) using daily precipitation data recorded in the period 1941-2007 (67 years) at 57 meteorological stations scattered across the area are studied at an annual scale. Trends in selected precipitation annual indices that are calculated from these data are investigated, in particular trends in the intensity, frequency and duration of extreme precipitation events. Special attention is dedicated to local and regional variability. The spatial correlations between the annual trends in mean precipitation and in the extremes are analysed. Moreover, the relationships between the variability of the North Atlantic Oscillation (NAO) index and several indices related to the frequency and intensity of the precipitation at the 57 stations were also investigated. Results show that several stations have predominantly negative tendencies in the precipitation indices, although the majority of stations did not show statistically significant change over time in the 1941-2007 period. At the regional level, the decreasing trend in the simple daily precipitation intensity index is the only one statistically significant at the 5 % level and appears to be related to the predominance of the positive phase of the NAO. For the period 1976-2007, the proportion of the total precipitation attributed to heavy and very heavy precipitation events increased and, consequently, daily precipitation events show a tendency to become more intense. Moreover, correlation analysis show that the most extreme events could be changing at a faster absolute rate in relation to the mean than more moderate events. [ABSTRACT FROM AUTHOR]

A method for ranking daily precipitation events is presented based on the most comprehensive database of daily gridded precipitation dataset available for the Iberian Peninsula spanning from 1950 to 2008. The magnitude of an event is obtained after considering the area affected as well as its intensity in every grid point and taking into account the daily normalized departure from climatology. Different precipitation rankings are presented considering the entire Iberian Peninsula, Portugal and also the six largest river basins in the Iberian Peninsula. [ABSTRACT FROM AUTHOR]

This study aims mostly at understanding seasonal variations in the intensity, frequency and duration of extreme precipitation events in mainland Portugal. For this purpose, selected precipitation indices that mainly focus on extremes were calculated at the seasonal scale for daily data recorded in the period 1941-2007 at 57 meteorological stations scattered across the area. These indices were explored for trends at the local and regional levels. The results show that there are marked changes in precipitation indices at the seasonal scale. Trends in spring and autumn precipitation have opposite signals. In spring, statistically significant drying trends are found together with a reduction in extremes. In autumn, wetting trends are detected for all indices, although overall they are not significant at the 5 % level. In addition, the relationship between seasonal extreme precipitation indices and atmospheric large-scale modes of low-frequency variability is analysed by means of a seasonal correlation analysis. Four modes of low-frequency variability are explored. Results confirm that, over mainland Portugal, the North Atlantic Oscillation is one of the most important teleconnection patterns in any season and the mode of variability that has the greatest influence on precipitation extremes in the area, particularly in the winter and autumn. [ABSTRACT FROM AUTHOR]

ABSTRACT This study provides a thorough assessment of recent changes in near-surface air temperature in mainland Portugal at both the local and regional level, focusing on extreme events (maximum and minimum) at a seasonal scale. It examines trends in selected specific indices that are calculated from daily air temperature data from 23 measuring stations scattered across the territory, recorded between 1941 and 2006. The results show overall warming trends over mainland Portugal that are consistent with the dominant global warming and reflect an increase in both maximum and minimum air temperature. When we split the study period into two sub-periods, 1945-1975 and 1976-2006, the partial trend analysis reveals that the first sub-period is mostly characterized by cooling followed by an even stronger tendency towards warmer benchmarks in all the indices evaluated, in particular for the warm-related temperature extremes in spring and summer. The changes observed in seasonal patterns confirm the well-known asymmetries in the climate in mainland Portugal and suggest that they are likely to be aggravated. There are changes associated with extreme temperatures, in particular, the significant increase in the frequency and duration of heat waves, and the increase in the frequency of hot days and tropical nights, especially in spring and summer; moreover there is a significant decrease in the frequency of cold waves and frost days. Teleconnections associated with changing patterns of temperature are also investigated. The results show that, over mainland Portugal, cold-related air temperature extremes have been associated with the East Atlantic mode in autumn, whereas warm-related extremes have been associated with the Scandinavia teleconnection pattern in spring, summer and autumn. However, the most prominent Northern Hemisphere pattern, the North Atlantic Oscillation, exerts limited influence, which is felt mostly in winter and spring. [ABSTRACT FROM AUTHOR]

Abstract: The Cloud to Ground lightning activity is analyzed for the Portugal mainland during the 2003–2009 period. Both inter-annual and intra-annual variability are clearly present. Winter months present a smaller number of Cloud to Ground discharges than the remaining warmer seasons. The highest density of discharges in the colder months is found in the coastal regions. On the contrary, for the remaining seasons, Cloud to Ground discharges tend to occur much more frequently in the interior areas of Portugal. A diurnal cycle of the Cloud to Ground discharges activity is clearly present in spring, summer and autumn, with maximum activity being found in the afternoon hours. The relationship between the Circulation Weather Types and Cloud to Ground discharges allowed us to distinguish which types are most frequently associated to lightning activity and also which types are the most favorable to present severe lightning episodes. Moreover, the analysis of additional meteorological fields allowed, at a seasonal scale, to discuss different mechanisms for lightning activity triggering: frontal activity, cut-off lows, and summer thermal lows are the most relevant in Portugal mainland. A case study is also provided for the most notorious event in terms of the total number of Cloud to Ground discharges (10th and 11th of September of 2007). [Copyright &y& Elsevier]

The aim of the work described herein was to study projection scenarios in order to find changes in the synoptic variability of the northwest Iberian Peninsula in the 21st century. To this end, we investigated the changes in the frequency of the different circulation types computed for the study area using three different models used in the IPCC 4th assessment report. The circulation types were computed using the procedure known as Lamb circulation types. The control simulation for the late 20th century was evaluated objectively from the results obtained using data from the NCEP/NCAR reanalysis, as to evaluate the ability of the model to reproduce the present climate. We have compared not only seasonal mean sea level pressure fields but also the mean seasonal frequency of circulation types. The results for the end of the 21st century show a decrease in the frequency of cyclonic, W, and SW circulation types in the spring and summer months. This trend also appears in the autumn, with a concomitant increase in the anticyclonic types. [ABSTRACT FROM AUTHOR]

Abstract: This paper analyses the impact of the 2003 European heatwave on excessive human mortality in Portugal, a country that presents a relatively high level of exposure to heatwave events. A total of 2399 excessive deaths are estimated in continental Portugal, which implies an increase of 58% over the expected deaths. When these values are split by gender, it is seen that women increase (79%), was considerably higher than that recorded for men (41%). The increment of mortality due to this heatwave was detected for all the 18 districts of the country, but its magnitude was significantly higher in the inner districts close to the Spanish border. When we split by gender all districts reveal significant mortality increments for women, while the impact in men''s excess deaths is not significant over 3 districts. Several temperature derived indices were used and evaluated in their capacity to explain, at the regional level, the excessive mortality (ratio between observed and expected deaths) by gender. It is shown that the best relationship is found for the total exceedance of extreme days, an index combining the length of the heatwave and its intensity. Both variables hold a linear relationship with r =0.79 for women and a poorer adjustment (r =0.50) for men. Additionally, availability of mortality data split by age also allowed obtaining detailed information on the structure of the population in risk, namely by showing that statistically significant increments are concentrated in the last three age classes (45–64, 65–74 and 75 or more). The use of air conditioning systems in some Portuguese hospitals had a major impact on the decrease (up to 40%) in excessive mortality values. A finer approach is relevant for prevention strategies, since it allows to identify better the target population of any preventive strategy regional and national authorities may be interested to implement. [Copyright &y& Elsevier]

The extratropical cyclones that originate in the North Atlantic and propagate towards Europe are one of the major natural hazards in mid-latitudes. In December 2019, three consecutive extratropical cyclones named Daniel, Elsa, and Fabien affected Portugal. In this study, the synoptic and upper-level dynamic conditions associated with these systems during their impact in mainland Portugal are evaluated. The persistent intense zonal flow that crossed the entire Atlantic revealed by the integrated vapor transport and the vertically integrated moisture flux favored these hydro-meteorological systems. The patterns of mean sea level pressure, geopotential, potential vorticity, total column water, and convective available potential energy were used to characterize the influence of every system over mainland Portugal. A cluster analysis of monthly precipitation permitted the classification of the country into four main regions named the Northwest, Centre West, Northeast and Centre East, and South region on which the analysis was focused. The three storms affected every region on consecutive days by the middle of December, producing extreme precipitation events and significant effects on the accumulated rainfall and runoff, particularly in the Northwest, Centre West, Northeast and Centre East regions. As consequence, multiple incidences of damage were reported along mainland Portugal. However, an assessment of the Standardized Precipitation Index (SPI) and the Standardized Precipitation–Evapotranspiration Index (SPEI) on time scales of 1, 3, 6, and 12 months revealed a positive impact of rainfall increase on the attenuation of short and long term accumulated drought conditions, particularly in the center and north regions. [ABSTRACT FROM AUTHOR]

In Portugal floods and landslides represent two of the most frequent and hazardous natural disasters. Information on past floods and landslides that caused significant human consequences in Portugal from 1865 onwards is gathered in the DISASTER database (Zêzere et al., 2014). This database was built under the assumption that socio-economic consequences of floods and landslides are relevant enough to be reported by regional and national newspapers, which were the data source and can be replicate elsewhere. The DISASTER database contains detailed information on the spatial location and human impacts (fatalities, injuries, missing people, evacuated and homeless people) of many hydro-geomorphologic cases (flood and landslide cases). These hydro-geomorphologic disaster cases are grouped in a restrict number of DISASTER events that were selected according to the following criteria: a set of at least 3 DISASTER cases sharing the same trigger in time (with no more than 3 days without cases) which have a widespread spatial extension related to the triggering mechanism and a certain magnitude. At total, 130 hydro-geomorphological events (HGE) were identified in Portugal mainland (938 fatalities and ~41000 homeless people). Each HGE was characterized with the following attributes: HGE type (e.g. landslides, floods, flash floods, urban floods); date of occurrence (year, month and days); duration in days; georeferenced spatial location; number of fatalities, injured, evacuated and homeless people (Pereira et al., 2018). Flood and landslide recorded in HGE database show that single damaging landslide events are very rare. The most common HGE is the occurrence of landslides and floods together since they often require long rainy periods and a higher soil water content. HGE compound events with both floods and landslides represent the highest percentage of events (~20% of events), while floods present the second highest percentage (~13%).Therefore, from the HGE database, a sub-set of HEG compound events was selected in order to provide a detailed analysis of each one of these events, including their human impacts, pre-conditioning precipitation analyses and the underlying atmospheric circulation that could have amplify the impact of the events.References: Pereira S, Ramos AM, Rebelo L, Trigo RM, Zêzere JL (2018) A centennial catalogue of hydro-geomorphological events and their atmospheric forcing. Advances in Water Resources, 122, 98-112.Zêzere JL, Pereira S, Tavares AO, Bateira C, Trigo RM, Quaresma I, Santos PP, Santos M, Verde J (2014) DISASTER: a GIS database on hydro-geomorphologic disasters in Portugal, Natural Hazards, 72(2), 503–532.This work was supported by the project FORLAND – Hydrogeomorphologic risk in Portugal: driving forces and application for land use planning [PTDC / ATPGEO / 1660/2014] funded by the Portuguese Foundation for Science and Technology (FCT), Portugal. The financial support for attending this workshop was also possible through the following FCT project: HOLMDRIVE - North Atlantic Atmospheric Patterns influence on Western Iberia Climate: From the Lateglacial to the Present [PTDC/CTA-GEO/29029/2017]. A. M. Ramos was also supported by a FCT postdoctoral grant (FCT/DFRH/ SFRH/BPD/84328/2012). [ABSTRACT FROM AUTHOR]

• Compared to the latest report, the fraction of fires ignited by lighting was smaller. • Ignitions by lightning were more frequent amongst larger fire occurrences. • During the compound events of 2003 and 2017, lightning was a relevant fire cause. • Remote sensing data was able to reproduce the seasonality of lightning-ignited fires. Fire databases typically contain information regarding the location, timing, and duration of fire occurrences, as well as the cause (natural or human-induced). These databases allow for the analysis and understanding of the circumstances surrounding the ignition and propagation of wildfires, being highly relevant when addressing fire suppression and management plans, or for improvement of prevention policies. In Portugal, a large number of fires in the official database have unknown causes, which limits the understanding about the relevance of each fire cause, in particular the role of lightning on the ignition of fires over the country. The objective of this paper is twofold: first, we investigated the spatial-temporal variability of lightning-induced fires from 2003 to 2020. Then, we evaluate the feasibility of using remote sensing data as a surrogate for identifying fire causes, through validation with the fire database. Our results revealed that lightning-ignited fires represent an even smaller fraction of all fire events than mentioned in the latest official report about fire causes in the country, accounting for only 1 % of the fire occurrences and 4.6 % of the total burned area in the 18-year period under analysis. The months of June to September comprise 91 % of all lightning fires, which occur more frequently in the northern, remote regions of the country and at relatively high altitudes. Moreover, lightning ignitions originate fires larger than the global average and contributed significantly to the total area burned during the extreme 2003 and 2017 fire seasons. Its importance in these extreme years suggests that lightning can trigger large fires when in conjunction with compound events such as droughts and heatwaves. When compared with in-situ databases, the application of remote sensing data reproduced the seasonality of lightning-ignited fires, but failed to account for the contribution of smaller fires, which represent the majority of occurrences in the Portuguese fire database. Finally, we discuss the implications of our findings for the improved assessment of fire risks, causes, and impacts in Portugal. [ABSTRACT FROM AUTHOR]

Predicting the environmental impact of climate change in extremely sensitive areas, like western Iberia, requires an understanding of the long-term interactions between climate and vegetation. Here we present a novel high-temporal resolution multiproxy analysis, including plant-wax n -alkane isotope data, pollen analysis, macrocharcoal identification, chironomid and diatom records of sediments from a mountain lake in central Portugal. We examined the evolution of the Atlantic and Mediterranean climate influences over the last two millennia, exploring their connection with major atmospheric patterns and impacts on the climatic signal and vegetation dynamics in this understudied region. During the Roman Period (RP; ca. -200 – 500 AD), the study area was characterized by grass dominance, with high temperatures indicated by chironomid composition and microcharcoal content. The increase in plant-wax δ2H values during this period suggests a shift from wet to dry conditions. The Early Middle Ages (EMA; ca. 500–900 AD) were characterized by colder and a transition to wetter conditions, as indicated by the vegetation and plant-wax n -alkane isotope data. The Medieval Climate Anomaly (MCA; ca. 900–1300 AD) was generally warm, with a short initial lake level drop. This period exhibits the maximum expansion of the Mediterranean forest over the last 2 ka and possibly proximal moisture sources. During the Little Ice Age (LIA; 1300–1850 AD), a reduction of the Mediterranean forest and a strong depletion of plant-wax δ2H values suggest cold and wet conditions with strong influence of remote Atlantic moisture, with the coldest and wettest phase of the last 2 ka detected between 1550 and 1900 AD. The post-LIA period, from 1900 AD onwards, shows a change to the present warmer and drier conditions, in a highly anthropized landscape. We also demonstrate that major changes in climate have influenced vegetation patterns, with these changes mainly controlled by large-scale atmospheric dynamics. This underscores the sensitivity of western Iberian ecosystems to climate shifts, enriches the current regional understanding of climate-vegetation interplay, and offers valuable insights for future climate change projections. • New multi-proxy analysis of Serra da Estrela lake sediments in central Portugal. • High-resolution plant-wax n-alkane isotopes reveal past climate shifts. • North Atlantic climate changes had a prompt impact on vegetation. • NAO modulated regional climate with other modes playing a secondary role. [ABSTRACT FROM AUTHOR]

Abstract: Changes in the climatology of precipitation and surface air temperature are being investigated worldwide, searching for changes in variability, the mean and extreme events (maximum and minimum). By exploring recent adjustments in the climate of mainland Portugal, particularly in the intensity, frequency and duration of extreme events, this study investigates trends in selected specific indices that are calculated from daily precipitation data from 57 and surface air temperature data from 23 measuring stations scattered across the territory. Special attention is paid to regional differences and variations in seasonality. The data cover the periods 1941–2007 for precipitation, and 1941–2006 for temperature. They are explored at the annual and seasonal scales and for different sub-periods. Results show that trends in annual precipitation indices are generally weak and, overall, not statistically significant at the 5% level. Nevertheless, a decreasing trend is revealed by regional indices of total wet-day precipitation and extreme precipitation (above the 99th percentile). Seasonal precipitation exhibits significant decreasing trends in spring precipitation, while extreme heavy precipitation events, in terms of both magnitude and frequency, have become more pronounced in autumn. Results for winter and summer suggest that the extremes have not suffered any significant aggravation. Trends for air temperature are statistically more significant and marked than for precipitation and indicate general warming across the territory. This warming trend is revealed very consistently by the time series of individual stations and regional mean temperature, and is also consistent with the findings reported in other studies for Portugal and at the European scale. [Copyright &y& Elsevier]

Wind extremes, heavy precipitation events and flooding occurring during extended winter over land in the mid latitudes are mostly associated with extratropical cyclones. It is well known that the Iberian Peninsula is prone to the occurrence of these compound events and associated hazards (Liberato et al., 2013; 2014). In this work a dataset of historical high-impact winter storms for the Iberian Peninsula is used to develop a systematic analysis and a catalogue of weather compound events. Additionally ERA5 reanalysis allow the assessment of the synoptic evolution, dynamical characteristics and the main impacts of the top-10 storms that provoked extreme impacts and considerable economical losses over Portugal.Liberato et al. 2013 Nat. Hazards Earth Syst. Sci., 13:2239-2251 doi: 10.5194/nhess-13-2239-2013Liberato 2014 Weather and Climate Extremes, 5-6: 16-28 doi: 10.1016/j.wace.2014.06.002AcknowledgmentsThis work is supported under projects UID/GEO/50019/2019 – Instituto Dom Luiz and WEx-Atlantic (PTDC/CTA-MET/29233/2017) by Fundação para a Ciência e a Tecnologia, Portugal (FCT) and Portugal Horizon 2020. FCT is also funding R. Hénin doctoral grant (PD/BD/114479/2016) and A.M. Ramos postdoctoral grant (FCT/DFRH/SFRH/BPD/84328/2012). [ABSTRACT FROM AUTHOR]