Search

Trends of extreme-temperature episodes in cities are increasing (in frequency, magnitude and duration) due to regional climate change in interaction with urban effects. Urban morphologies and thermal properties of the materials used to build them are factors that influence spatial and temporal climate variability and are one of the main reasons for the climatic singularity of cities. This paper presents a methodology to evaluate the urban and peri-urban effect on extreme-temperature exposure in Barcelona (Spain), using the Local Climate Zone (LCZ) classification as a basis, which allows a comparison with other cities of the world characterised using this criterion. LCZs were introduced as input of the high-resolution UrbClim model (100 m spatial resolution) to create daily temperature (median and maximum) series for summer (JJA) during the period 1987 to 2016, pixel by pixel, in order to create a cartography of extremes. Using the relationship between mortality due to high temperatures and temperature distribution, the heat exposure of each LCZ was obtained. Methodological results of the paper show the improvement obtained when LCZs were mapped through a combination of two techniques (land cover–land use maps and the World Urban Database and Access Portal Tools – WUDAPT – method), and the paper proposes a methodology to obtain the exposure to high temperatures of different LCZs in urban and peri-urban areas. In the case of Barcelona, the distribution of temperatures for the 90th percentile (about 3–4 ∘ C above the average conditions) leads to an increase in the relative risk of mortality of 80 %. [ABSTRACT FROM AUTHOR]

Trends of extreme temperature episodes in cities are increasing (in frequency, magnitude and duration) due to regional climate change in interaction with the urban effects. Urban morphologies and thermal properties of the materials used to build them are factors that influence the spatial and temporal climate variability and becomes one of the main reasons for the climatic singularity of cities. This paper presents a proposal to evaluate the urban and peri-urban effect on extreme temperatures exposure in Barcelona (Spain), using the Local Climate Zone (LCZ) framework as a base statement, that allows the comparison with other cities of the world characterized using this criterion. LCZs were introduced as input of the high resolution UrbClim model (100 m spatial resolution) to create the daily temperatures (median and maximum) series for summer (JJA) during the period 1987 to 2016, pixel by pixel, in order to create a cartography of extremes. Using the relationship between mortality due to high temperatures and the temperature distribution, the heat exposure of each LCZ was obtained. Methodological results of the paper show the improvement obtained when LCZs were mapped through a combination of two techniques (from Land Cover/Land Use maps and from WUDAPT method), as well as proposes a methodology to obtain the exposure to high temperatures of different LCZs on urban and peri-urban areas. In the case of Barcelona, the distribution of temperatures for the 90th percentile (about 3–4 °C compared to average conditions) leads to an increase in the relative risk of mortality of 80 %. [ABSTRACT FROM AUTHOR]

Despite the current developments in flood forecasting and emergency management, floods still consist a significant threat to people and properties. At a national level in Europe, data on flood fatalities are fragmentary and they are mainly focused on death toll, without providing further details regarding victims' characteristics or the circumstances under which the deadly events have taken place. However, such details could enlighten us on what happened wrong when there was a victim due to a flood, and what measures should be taken in order to avoid similar events in the future. This paper presents the EUFF 2020 database (EUropean Flood Fatalities-FF) (EUropean Flood Fatalities-FF) (https://doi.org/10.4121/uuid:489d8a13-1075-4d2f-accb-db7790e4542f, Petrucci et al., 2020) which collects data from 2483 flood deadly cases occurred in a 39-year period (1980-2018) in 8 countries and 9 (two belong in Spain) study areas (Czech Republic, Israel, Italy, Turkey, Greece, Portugal, South France, Catalonia and Balearic Islands). EUFF 2020 (Petrucci et al., 2020) attempts to shed light on fatal flood events in the Euro-Mediterranean region under various geomorphological and climatic settings. The paper presents both regional and super-regional analyses from gender, age, conditions, activity of fatalities and dynamics of the accidents point of view aiming to contribute to a better understanding of the population exposure to floods phenomena. The historical research, which was carried out by using local documentary sources, highlights that 64.8 % of FF have been due to flood events in which less than 10 people were killed. Due to this relatively small number of losses, these events have not been recorded in the international disaster databases. Flood events causing single and multiple fatalities occurred throughout the period of our analysis without showing any particular remarkable trend. Data confirm that victim's gender only, is not a de facto driver of social vulnerability. In addition, females flood fatalities are quantitatively more than males. Males' vulnerability depends on a stronger exposure to floods, due to the higher proportion of males driving vehicles, doing outdoorsworking activities and sometimes undertaking risky actions. The majority of fatalities are people in their most productive working age (between 30 and 64 years old), who are exposed to floods outdoor while heading from home to work or vice-versa. Elderly people (in status of retirement) seem to be more frequently affected while being indoor, trapped by the flood in their premises, while adults and children are dragged outdoors. Driving car or any other kind of vehicles are the most frequent conditions of victims in all studied areas, for both males and females, as widely stated in literature. The EUFF 2020 database can be extended spatially and temporally, and it represents a European database of high scientific and practical potential for further use in various scientific disciplines. We hope, EUFF 2020 database will further motivate researchers to enrich with even more data on flood fatalities from their home countries. Spatial extension will allow the comparison of local frameworks in broader European scale and the identification of useful general and local features of risk management and educational campaigns. We believe that the followed pan-European approach, frames the anticipation of flood fatality risk into a broader context, promising benefit for diverse scientific disciplines and contributing to public policies and civil protection campaigns in order to reduce the number of floods' fatalities in the future. [ABSTRACT FROM AUTHOR]

Flooding is one of the main natural hazards in the world and causes huge economic and human impacts. Assessing the flood damage in the Mediterranean region is of great importance, especially because of its large vulnerability to climate change. Most past floods affecting the region were caused by intense precipitation events; thus the analysis of the links between precipitation and flood damage is crucial. The main objective of this paper is to estimate changes in the probability of damaging flood events with global warming of 1.5, 2 and 3 ∘ C above pre-industrial levels and taking into account different socioeconomic scenarios in two western Mediterranean regions, namely Catalonia and the Valencian Community. To do this, we analyse the relationship between heavy precipitation and flood-damage estimates from insurance datasets in those two regions. We consider an ensemble of seven regional climate model (RCM) simulations spanning the period 1976–2100 to evaluate precipitation changes and to drive a logistic model that links precipitation and flood-damage estimates, thus deriving statistics under present and future climates. Furthermore, we incorporate population projections based on five different socioeconomic scenarios. The results show a general increase in the probability of a damaging event for most of the cases and in both regions of study, with larger increments when higher warming is considered. Moreover, this increase is higher when both climate and population change are included. When population is considered, all the periods and models show a clearly higher increase in the probability of damaging events, which is statistically significant for most of the cases. Our findings highlight the need for limiting global warming as much as possible as well as the importance of including variables that consider change in both climate and socioeconomic conditions in the analysis of flood damage. [ABSTRACT FROM AUTHOR]

Flooding is one of the main natural hazard in the world and causes huge economic and human impacts. Assessing the flood damage in the Mediterranean region is of great importance, especially because its large vulnerability to climate change. Most past floods affecting the region were caused by intense precipitation events, thus the analysis of the links between precipitation and flood damage is crucial. The main objective of this paper is to estimate changes in the probability of damaging flood events with a global warming of 1.5, 2 and 3 °C above preindustrial levels and taking into account different socioeconomic scenarios in two western Mediterranean regions, namely Catalonia and the Valencian Community. To do this, we analyse the relationship between heavy precipitation and flood damage estimates from insurance datasets in those two regions. We consider an ensemble of seven regional climate model simulations spanning the period 1976–2100 to evaluate precipitation changes and to drive a logistic model that links precipitation and flood damage estimates, and thus to derive statistics under present and future climates. Furthermore, we incorporate population projections based on 5 different socioeconomic scenarios. The results show a general increase in the probability of a damaging event for most of the cases and in both regions of study, with larger increments when higher warming is considered. Moreover, this increase is higher when both climate and population change are included. When population is considered, all the periods and models show a clearly higher increase in the probability of damaging events, which is statistically significant for most of the cases. [ABSTRACT FROM AUTHOR]

Societal exposure to large fires has been increasing in recent years. Estimating the expected fire activity a few months in advance would allow reducing environmental and socio-economic impacts through short-term adaptation and response to climate variability and change. However, seasonal prediction of climate-driven fires is still in its infancy. Here, we discuss a strategy for seasonally forecasting burned area anomalies linking seasonal climate predictions with parsimonious empirical climate–fire models using the standardized precipitation index as the climate predictor for burned area. Assuming near-perfect climate predictions, we obtained skilful predictions of fire activity over a substantial portion of the global burnable area (~60%). Using currently available operational seasonal climate predictions, the skill of fire seasonal forecasts remains high and significant in a large fraction of the burnable area (~40%). These findings reveal an untapped and useful burned area predictive ability using seasonal climate forecasts, which can play a crucial role in fire management strategies and minimise the impact of adverse climate conditions. [ABSTRACT FROM AUTHOR]

Floods in the Mediterranean region are often surface water floods, in which intense precipitation is usually the main driver. Determining the link between the causes and impacts of floods can make it easier to calculate the level of flood risk. However, up until now, the limitations in quantitative observations for flood-related damages have been a major obstacle when attempting to analyse flood risk in the Mediterranean. Flood-related insurance damage claims for the last 20 years could provide a proxy for flood impact, and this information is now available in the Mediterranean region of Catalonia, in northeast Spain. This means a comprehensive analysis of the links between flood drivers and impacts is now possible. The objective of this paper is to develop and evaluate a methodology to estimate flood damages from heavy precipitation in a Mediterranean region. Results show that our model is able to simulate the probability of a damaging event as a function of precipitation. The relationship between precipitation and damage provides insights into flood risk in the Mediterranean and is also promising for supporting flood management strategies. [ABSTRACT FROM AUTHOR]

The climate change impact on mean and extreme precipitation events in the northern Mediterranean region is assessed using high-resolution EuroCORDEX and Med- CORDEX simulations. The focus is made on three regions, Lez and Aude located in France, and Muga located in northeastern Spain, and eight pairs of global and regional climate models are analyzed with respect to the SAFRAN product. First the model skills are evaluated in terms of bias for the precipitation annual cycle over historical period. Then future changes in extreme precipitation, under two emission scenarios, are estimated through the computation of past/future change coefficients of quantile-ranked model precipitation outputs. Over the 1981-2010 period, the cumulative precipitation is overestimated for most models over the mountainous regions and underestimated over the coastal regions in autumn and higher-order quantile. The ensemble mean and the spread for future period remain unchanged under RCP4.5 scenario and decrease under RCP8.5 scenario. Extreme precipitation events are intensified over the three catchments with a smaller ensemble spread under RCP8.5 revealing more evident changes, especially in the later part of the 21st century. [ABSTRACT FROM AUTHOR]

As flood impacts are increasing in large parts of the world, understanding the primary drivers of changes in risk is essential for effective adaptation. To gain more knowledge on the basis of empirical case studies, we analyze eight paired floods, that is, consecutive flood events that occurred in the same region, with the second flood causing significantly lower damage. These success stories of risk reduction were selected across different socioeconomic and hydro-climatic contexts. The potential of societies to adapt is uncovered by describing triggered societal changes, as well as formal measures and spontaneous processes that reduced flood risk. This novel approach has the potential to build the basis for an international data collection and analysis effort to better understand and attribute changes in risk due to hydrological extremes in the framework of the IAHSs Panta Rhei initiative. Across all case studies, we find that lower damage caused by the second event was mainly due to significant reductions in vulnerability, for example, via raised risk awareness, preparedness, and improvements of organizational emergency management. Thus, vulnerability reduction plays an essential role for successful adaptation. Our work shows that there is a high potential to adapt, but there remains the challenge to stimulate measures that reduce vulnerability and risk in periods in which extreme events do not occur. [ABSTRACT FROM AUTHOR]

The climate change impact on mean and extreme precipitation events in the northern Mediterranean region is assessed over high resolution EuroCORDEX and MedCORDEX simulations. The focus is made on three regions, the Lez and the Aude located in France, and the Muga, located in northeastern Spain and eight pairs of global and regional climate models are analyzed with respect to the SAFRAN product. First the model skills are evaluated in terms of bias for the precipitation annual cycle over past period. Then future changes in extreme precipitation, under two emission scenarios, are estimated through the computation of past/future change coefficients of quantile-ranked model precipitation outputs. Over past period, the cumulative precipitation is overestimated for most models over the mountainous regions and underestimated over the coastal regions in autumn and higher order quantile. The ensemble mean and the spread for future period remain unchanged under RCP4.5 scenario and decrease under RCP8.5 scenario. Extreme precipitation events are intensified over the three catchments with a smaller ensemble spread under RCP8.5 revealing more evident changes, especially in the last part of the 21th century. [ABSTRACT FROM AUTHOR]

Forest fires are a serious environmental hazard in southern Europe. Quantitative assessment of recent trends in fire statistics is important for assessing the possible shifts induced by climate and other environmental/socioeconomic changes in this area. Here we analyse recent fire trends in Portugal, Spain, southern France, Italy and Greece, building on a homogenized fire database integrating official fire statistics provided by several national/EU agencies. During the period 1985-2011, the total annual burned area (BA) displayed a general decreasing trend, with the exception of Portugal, where a heterogeneous signal was found. Considering all countries globally, we found that BA decreased by about 3020 km2 over the 27-year-long study period (i.e. about -66% of the mean historical value). These results are consistent with those obtained on longer time scales when data were available, also yielding predominantly negative trends in Spain and France (1974-2011) and a mixed trend in Portugal (1980-2011). Similar overall results were found for the annual number of fires (NF), which globally decreased by about 12600 in the study period (about -59%), except for Spain where, excluding the provinces along the Mediterranean coast, an upward trend was found for the longer period. We argue that the negative trends can be explained, at least in part, by an increased effort in fire management and prevention after the big fires of the 1980’s, while positive trends may be related to recent socioeconomic transformations leading to more hazardous landscape configurations, as well as to the observed warming of recent decades. We stress the importance of fire data homogenization prior to analysis, in order to alleviate spurious effects associated with non-stationarities in the data due to temporal variations in fire detection efforts. [ABSTRACT FROM AUTHOR]

In this study we explore the seasonal predictability of summer wildfires in a Mediterranean region (northeastern Spain), developing a multiple linear regression model with antecedent and current-summer drought indices (Standardised Precipitation Index; and Standardised Precipitation Evapotranspiration Index). This model is based on the assumption that large summer fires in Mediterranean environments are favoured by current-summer drought (proxy for the climatic factors that affect fuel flammability) and by antecedent wet conditions (proxies for the climatic factors influencing fine fuel availability and connectivity). We test three forecast systems based on (i) seasonal European Centre for Medium-Range Weather Forecasts (ECMWF) System-4 forecasts; (ii) persistence and (iii) climatology. These approaches are evaluated through a leave-one-out cross-validation over the period 1983-2012. The climatology forecast, which considers only antecedent wet or dry conditions with a time lag of 2 years, shows some amount of skill in simulating above- or below-normal summer fire activity. ECMWF System-4 proves to be of limited added value with respect to the climatology forecast. Finally, the persistence forecast, which is driven by antecedent conditions and drought conditions just before the start of the fire season, allows more satisfactory results (correlation of 0.49). The results suggest that long-term forecasts of above-normal burned area are feasible in Catalonia (north-eastern Spain), information that could be potentially applied also to other Mediterranean-type regions. [ABSTRACT FROM AUTHOR]

The analysis of both observed climate and fire data from 1970 to 2007 in a typical Mediterranean environment (i.e., the North-eastern Iberian Peninsula) shows that the warming climate forcing alone would have led to a positive trend in the Number of Fires (NF) and a slightly negative trend in the Burned Area (BA) in summer. This is in contrast to the common expectation that warming should result in larger fires. In fact, for BA, probably less favourable conditions for both fine fuel availability and fuel connectivity counterbalance the increase in fuel flammability. Climate projections from the ENSEMBLES Project indicate that warming will continue up to at least 2050, promoting more numerous fires but of similar or slightly smaller extension. These results suggest the necessity for a more intense fire management effort in order to maintain the number of fires at least at the same level as today. [ABSTRACT FROM AUTHOR]

The present paper shows an in-depth analysis of the evolution of floods and precipitation in Catalonia for the period 1981–2010. In order to have homogeneous information, and having in mind that not gauge data was available for all the events, neither for all the rivers and stream flows, daily press from a specific newspaper has been systematically analysed for this period. Furthermore a comparison with a longer period starting in 1900 has been done. 219 flood events (mainly flash flood events) have been identified for the period of 30 years (375 starting in 1900), 79 of them were ordinary, 117 of them were extraordinary and 23 of them were catastrophic, being autumn and summer the seasons with the maxima values. 19% of the events caused a total of 110 casualties. 60% of them died when they tried to cross the street or the stream. Factors like the evolution of precipitation, population density and other socio-economical aspects have been considered. The trend analysis shows an increase of 1 flood/decade that probably has been mainly due to inter-annual and intra-annual changes in population density and in land-use and land-cover. [ABSTRACT FROM AUTHOR]

Recent events in Western Attica in Greece (24 deaths in November 2017), in the Balearic Islands (13 deaths in October 2018), and in southern France (15 deaths in October 2018) show that flood-related mortality remains a major concern in Mediterranean countries facing flash floods. Over the past several years, many initiatives have arisen to create databases on flood-related mortality. An international initiative started in 2011 pooling regional and national databases on flood mortality from region and/or countries bordering the Mediterranean Sea. The MEditerranean Flood Fatality Database (MEFF DB) brings together, in 2018, six Mediterranean regions/countries: Catalonia (Spain), Balearic Islands (Spain), Southern France, Calabria (Italy), Greece, and Turkey, and covers the period 1980–2018. MEFF DB is on progress and, every year, new data are included, but for this study, we kept only the preliminary data that were geolocated and validated on 31st of December 2018. This research introduces a new step in the analysis of flood-related mortality and follows the statistical description of the MEFF DB already published. The goals of this paper are to draw the spatial distribution of flood mortality through a geographical information system (GIS) at different spatial scales: country, NUTS 3 (Nomenclature of Territorial Units for Statistics. Level 3) regions, catchment areas, and grid. A fatality rate (F: number of deaths/year/million of inhabitants) is created to help this analysis. Then, we try to relate mortality to basic (human or physical) drivers such as population density, rainfall seasonality, or rainfall frequency across the Mediterranean Basin. The mapping of F shows a negative mortality gradient between the western and the eastern parts of the Mediterranean Sea. The south of France appears to be the most affected region. The maps also highlight the seasonality of flood-related deaths with the same west–east gradient. It confirms that flood mortality follows the climatological seasonal patterns across the Mediterranean Basin. Flood-related fatalities mainly occur during the early fall season in the western part of the Mediterranean area, while the Easter Basin is affected later, in November or during the winter season. Eastern Turkey introduces another pattern, as mortality is more severe in summer. Mortality maps are then compared with factors that potentially contribute to the occurrence of flood fatalities, such as precipitation intensity (rainfall hazard), to explain geographical differences in the fatality rate. The density of a fatal event is correlated to the population density and the rainfall frequency. Conversely, the average number of deaths per event depends on other factors such as prevention or crisis management. [ABSTRACT FROM AUTHOR]