Search

The correlation analysis between precipitation indices and aerobiological variables could lead to different results if seasonal rainfall is considered. The number of significant correlations, as well as the ratio of positive/negative correlations, is higher when previous autumn rainfall is taken into account than for annual rainfall. However, the percentage of significant correlations is only 5.1 % of the total possible correlations. The autumn indices showing more correlations are related to rainfall duration and persistence, while those for winter were related to rainfall amount and intensity. Since the influence of moderately extreme rainfall seems to be low, the reported probable increase, due to climate change, of the occurrence of intense and short rainy events in the Mediterranean area in autumn does not seem that will have an appreciable effect by itself on the subsequent pollen production.

18 Pags.- 8 Figs.- 45 Tabls. © 2022 Lizaga, Latorre, Gaspar, Ramos and Navas. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY)., Recent land use changes, the absence of soil protection between crop periods, and extreme precipitation events have been highlighted as major influential factors in the fluctuations of sediment export in the last decades at the catchment scale worldwide. In this regard, soil erosion and fine-particle export are two of the major concerns of soil nutrient loss and water-quality decrease (e.g., increasing turbidity and vector of chemicals). However, while rainfall effects have been well-monitored, recent land use changes and management need additional approaches to evaluate their effect. In Mediterranean mountainous environments, in addition to forest management, agricultural practices during different cropland stages likely increase sediment and particle-bound chemicals in the drainage system. Moreover, most catchments lack instrumentalization. Thus, there is a gap in the knowledge on the processes influencing the sediment exported in ungauged catchments. To evaluate the processes involved, remote sensing and seasonal sampling of suspended sediments were examined for 5 years in a representative agroforestry system in three sub-catchments (SBCs) with different proportions of land uses. Temporal trends of NDVI, EVI, MSAVI, SAVI, and NDWI indices were analyzed for monitoring the vegetation status. With this information, we attempt to evaluate the soil response in terms of particle size export to land use change, vegetation status, and precipitation distribution in fine-grained sediment-reaching streams. Our findings not only highlight the significant effect of heavy precipitation events and vegetation cover on the grain-size fraction of the exported sediment but also reveal the existence of more complex factors influencing the export dynamics. A silt-increasing trend due to the increase of individual heavy precipitations from 2017 onward despite the total precipitation amount not increasing was detected. It is shown that indices such as NDVI and NDMI help detect small changes in vegetation cover, while EVI, SAVI, and MSAVI are more robust for detecting general patterns in large vegetated areas and preventing the appearance of artefacts in the data. Results from this study suggest that land use changes combined with short-scale changing trends of rainfall likely explain most of the possible effects observed in terms of sediment export changes., This research is part of the Project I+D+i PID 2019-104857RB-I00, funded by the MCIN/AEI/10.13039/501100011033/. This work represents a contribution to CSIC Interdisciplinary Thematic Platform (PTI) Teledetección (PTI-TELEDETECT). The contribution of IL was partially supported by the Research Foundation-Flanders (FWO, mandate 12V8622N).

International audience; A methodology to process radar wind profiler Doppler spectra is presented and implemented for an UHF Degreane PCL1300 system. First, double peak signal detection is conducted at each height level and, then, vertical continuity checks for each radar beam ensure physically consistent measurements. Second, horizontal and vertical wind, kinetic energy flux components, Doppler moments, and different precipitation-related variables are computed. The latter include a new precipitation type estimate, which considers rain, snow, and mixed types, and, finally, specific variables for liquid precipitation, including drop size distribution parameters, liquid water content and rainfall rate. The methodology is illustrated with a 48 h precipitation event, recorded during the Cerdanya-2017 field campaign, carried out in the Eastern Pyrenees. Verification is performed with a previously existing process for wind profiler data regarding wind components, plus precipitation estimates derived from Micro Rain Radar and disdrometer observations. The results indicated that the new methodology produced comparable estimates of wind components to the previous methodology (Bias < 0.1 m/s, RMSE ≈ 1.1 m/s), and was skilled in determining precipitation type when comparing the lowest estimate of disdrometer data for snow and rain, but did not correctly identify mixed precipitation cases. The proposed methodology, called UBWPP, is available at the GitHub repository.

El canvi climàtic i l’escalfament global és un problema que s’estudia en les darreres dècades i cada cop és més evident. Alguns dels canvis que s’han observat han estat la sequera i els incendis d’aquest darrer estiu. Així mateix, ha comportat problemes amb les reserves d’aigua provocant la declaració de l’alerta hidrològica a diversos municipis. Tot això mostra un futur molt incert respecte al recurs aigua. L’objectiu d’aquest treball és fer un estudi tecno-econòmic de la implementació futura de noves tecnologies, emprant un sistema híbrid de gestió, a les ciutats de Girona i Tarragona Climate change and global warming is a problem that has been studied in recent years decades and it is becoming more and more evident. Some of the changes that have been observed have been the drought and the fires of this last summer. Likewise, it has brought problems with the water reserves causing the declaration of the hydrological alert to several municipalities All this shows a very uncertain future regarding the water resource. The aim of this work is to make a techno-economic study of the future implementation of new technologies, using a hybrid management system, in the cities of Girona and Tarragona

Enhanced UV radiation levels and decreased rainfall in Mediterranean terrestrial ecosystems due to climate change might impact soil bacterial communities, significantly altering their structure and affecting biogeochemical cycles. The aim of this study was to evaluate the effect of UV-B and UV-A radiation on soil bacterial richness, abundance and community composition in a Typic Dystroxerept of Mediterranean shrubland and to determine whether these effects depend on reduced rainfall and/or soil physicochemical properties. Soils were subjected to long-term UV conditions: UV-A + UV-B exclusion (UV0 plots), UV-B exclusion (UVA plots), or ambient UV-A + UV-B exposure (UVAB plots), and combined with two rainfall regimes, natural (NR) and reduced (RR) rainfall. Barcoded amplicon 16S rRNA gene sequencing was used to analyse changes in microbial diversity. UV radiation did not affect bacterial richness and diversity indexes and only minor differences in species composition were observed. Unidentified species of the Longimicrobiaceae appeared to be in greater abundance in the UV0 plots than in the UVA and UVAB, especially under natural rainfall, whereas members of the Pyrinomonadaceae and Ktedonobacteraceae were more abundant in UVAB. Rainfall reduction resulted in lower bacterial abundance but higher diversity (Shannon–Weiner and InvSimpson indexes) under UV exclusion. The results pointed to a combined response of soil bacterial communities to UV radiation and rainfall treatments. However, the small changes observed suggest a high resilience of the Mediterranean shrubland soil microbiome to the projected changes in UV and rainfall conditions. Highlights: Microbial abundance and diversity were analysed in Mediterranean soils exposed to contrasted UV radiation and rainfall treatments Reduced rainfall exerted a greater effect on soil bacteria than UV radiation exposure. Limited effects of UV and rainfall changes support a high resilience of soil bacterial communities Agència de Gestió d'Ajuts Universitaris i de Recerca. Grant Numbers: 2017SGR0055, 2017SGR548; Ministerio de Ciencia e Innovación. Grant Numbers: CGL2012-22283, CGL2014-55976-R. Open Access funding provided thanks to theCRUE-CSIC agreement with Wiley

Rainfall behavior is a fundamental issue in areas with scarce and irregular amounts, such as the Spanish Mediterranean region. We identified 12 spatial patterns that characterized 899 torrential precipitation events (≥150 mm in 24 h) that occurred in the 3,537 rainy precipitation series in the period 1950–2020. Three of these components––eastern and ESE––showed positive and significant trends in their accumulated volumes. We then characterized the mean synoptic causes of the 10 most intense events in each component at both mean sea-level pressure and 500 hPa geopotential height, and also the integrated water-vapor transport between 1,000 and 300 hPa. We found a clear spatial distribution of the pluviometric effects related to unstable atmospheric situations (such as troughs and cut-off lows), and also to SW–SE advection fluxes that brought moist air from the Western Mediterranean. In particular, torrential rainfall in the Balearic Islands related more to E–NE advections than to southeastern ones. We also determined that the major parts of these components occurred in early autumn, especially in September and October. We expect these findings to help our understanding of the processes leading to catastrophic situations along the Spanish Mediterranean coast and to lead to improvements in early alert systems and management plans. The authors want to thank the Proyecto UTA-Mayor N° 5807–22 from the Universidad de Tarapacá, Chile. MLC, JMV, PS and OMR want to thank the Climatology Group (2017SGR1362, Catalan Government). RSN is partially supported by the Universidad Autónoma de Madrid (UAM) and the Comunidad de Madrid through project SI3-PJI-2021-00398, the Natural Hazards and Global Change research group from UAM, and the Government of Aragón through the “Program of research groups” (group H09_20R, “Climate, Water, Global Change, and Natural Systems”). JJM and MJE participation has been funded by the Spanish Ministerio de Ciencia e Innovación through the research project PID2020-118797RB-I00 (MCIN/AEI/10.13039/501100011033) and by Generalitat Valenciana through the research project PROMETEO/2021/016 (Conselleria d’Innovació, Universitats, Ciència i Societat Digital).

For the first time, this article presents a large dataset of precipitation isotopic measurements (δ18Op and δ2Hp) sampled every day or 2 d from seven sites on a west-to-east transect across northern Spain for 2010–2017. The main aim of this study is to (1) characterize the rainfallisotopic variability in northern Spain at daily and monthly timescales and (2) assess the principal factors influencing rainfall isotopic variability. The relative role of air temperature and rainfall in determining the stable isotope composition of precipitation changes along the west-to-east transect, with air temperature being highly correlated with δ18Op at daily and monthly timescales, while a few sites along the transect show a significant negative correlation with precipitation. The highest air temperature–δ18Op dependency is found for a station located in the Pyrenees. Frontal systems associated with North Atlantic cyclones are the dominant mechanism inducing precipitation in this region, particularly in winter. This study allows an exploration of the role of air mass source and trajectory in determining the isotopic composition of rainfall in northern Iberia by characterizing the moisture uptake for three of the seven stations. The importance of continental versus marine moisture sources is evident, with clear seasonal and spatial variations. In addition, the type of precipitation (convective versus frontal rainfall) plays a key role, with convective rainfall associated with higher δ18Op values. This comprehensive spatio temporal approach to analyzing the rainfall isotopic composition represents another step forward towards developing a more detailed, mechanistic framework for interpreting stable isotopes in rainfall as a paleoclimate and hydrological tracer., This research has been supported by the Agencia Estatal de Investigación (grant nos. CGL2016-77479-R, PID2019-106050RB-100, and CTM2013-48639-C2-2-R). We acknowledge support for the publication fee by the CSIC Open-Access Publication Support Initiative through its Unit of Information Resources for Research (URICI)

The influence of Madden–Julian Oscillation (MJO) on the dynamics ofextreme rainfall events during austral Spring in Uruguay is investigated. Theresearch is focused on the southern region of the country, which includes15 weather stations. Extreme events are defined as days in which accumulatedrainfall exceeds the 90 percentile of rainy days, and MJO is classified accordingto the Real-time Multivariate MJO series 1 (RMM1) and 2 (RMM2) indices.Given that the extratropical teleconnections associated with MJO take at least1 week to set up, we explore the influence of MJO up to 11 days prior toextreme events. A nonlinear time series analysis is performed (using symbolicpatterns known as ordinal patterns) in order to consider the effects of the per-sistence of particular phases of MJO on the dynamic of extreme rainfall events.We find that MJO has the highest influence on extreme rainfall events in theregion when it shows a persistence in phases 4 and 5 for more than 5 days,which intensifies the polar jet, influencing the trajectories of the transientwaves that propagate in high latitudes, favouring geopotential disturbancesover Uruguay. In other cases, the atmospheric pattern that leads to extremerainfall events is characterized by a blocking episode that prevents transientactivity from high latitudes to reach Uruguay, and the disturbances associatedwith the extreme events propagate along the subtropics.

Sol·licitant de l’informe: Gerència d'Urbanisme

This study looks into the future of evolving triggering rainfall conditions in a changing climate, and aims to establish a link to tools in the present to assess shallow landslide susceptibility. Focus is given to the triggering rainfall conditions represented by extreme daily rainfall and mean seasonal rainfall. The study site selected in this research was Wanzhou County, China. This county lies in a region of China that receives 90% of its annual rainfall during the summer months. The effect of which is observed with 80% of shallow landslides occurring between June to August from 1995-2005. This research project delivered proof-of-concept for a methodological framework to derive shallow landslide triggering rainfall scenarios from climate model outputs. The presentation of the results and the identification of sources of uncertainties in this study demonstrated a viable link between for climate change projections to provide future rainfall scenarios as inputs for physically-based shallow landslide susceptibility models.

As part of the EUREC4A field campaign, the research vessel Maria S. Merian probed an oceanic region between 6° N and 13.8° N and 51° W to 60° W for approximately 32 days. Trade wind cumulus clouds were sampled in the trade-wind alley region east of Barbados as well as in the transition region between the trades and the intertropical convergence zone, where the ship crossed some mesoscale oceanic eddies. We collected continuous observations of cloud and precipitation profiles at unprecedented vertical resolution (7–10 m in the first 3000 m) and high temporal resolution (1–3 s) using a W-band radar and micro-rain radar (MRR-PRO), installed on an active stabilization platform to reduce the impact of ship motions on the observations. The paper describes the ship motion correction algorithm applied to the Doppler observations to extract corrected hydrometeors vertical velocities and the algorithm created to filter interference patterns in the MRR-PRO observations. Radar reflectivity, mean Doppler velocity, spectral width and skewness for W-band and attenuated reflectivity, mean Doppler velocity and rain rate for MRR-PRO are shown for a case study to demonstrate the potential of the high resolution adopted. As non-standard analysis, we also retrieved and provided liquid water path (LWP) from the 89 GHz passive channel available on the W-band radar system. All datasets and hourly and daily quicklooks are publically available. Data can be accessed and basic variables can be plotted online via the intake catalog of the online book "How to EUREC4A".

This paper describes a methodology for processing spectral raw data from Micro Rain Radar (MRR), a K-band vertically pointing Doppler radar designed to observe precipitation profiles. The objective is to provide a set of radar integral parameters and derived variables, including a precipitation type classification. The methodology first includes an improved noise level determination, peak signal detection and Doppler dealiasing, allowing us to consider the upward movements of precipitation particles. A second step computes for each of the height bin radar moments, such as equivalent reflectivity (Ze), average Doppler vertical speed (W), spectral width (s), the skewness and kurtosis. A third step performs a precipitation type classification for each bin height, considering snow, drizzle, rain, hail, and mixed (rain and snow or graupel). For liquid precipitation types, additional variables are computed, such as liquid water content (LWC), rain rate (RR), or gamma distribution parameters, such as the liquid water content normalized intercept (Nw) or the mean mass-weighted raindrop diameter (Dm) to classify stratiform or convective rainfall regimes. The methodology is applied to data recorded at the Eastern Pyrenees mountains (NE Spain), first with a detailed case study where results are compared with different instruments and, finally, with a 32-day analysis where the hydrometeor classification is compared with co-located Parsivel disdrometer precipitation-type present weather observations. The hydrometeor classification is evaluated with contingency table scores, including Probability of Detection (POD), False Alarm Rate (FAR), and Odds Ratio Skill Score (ORSS). The results indicate a very good capacity of Method3 to distinguish rainfall and snow (PODs equal or greater than 0.97), satisfactory results for mixed and drizzle (PODs of 0.79 and 0.69) and acceptable for a reduced number of hail cases (0.55), with relatively low rate of false alarms and good skill compared to random chance in all cases (FAR < 0.30, ORSS > 0.70). The methodology is available as a Python language program called RaProM at the public github repository This research was funded by the Spanish Government through projects CGL2015-65627-C3-1-R, CGL2015-65627-C3-2-R (MINECO/FEDER), CGL2016-81828-REDT and RTI2018-098693-B-C32 (AEI/FEDER).

Collected rainfall records by gauges lead to key forcings in most hydrological studies. Depending on sensor type and recording systems, such data are characterized by different time-resolutions (or temporal aggregations), ta. We present an historical analysis of the time-evolution of ta based on a large database of rain gauge networks operative in many study areas. Globally, ta data were collected for 25,423 rain gauge stations across 32 geographic areas, with larger contributions from Australia, USA, Italy and Spain. For very old networks early recordings were manual with coarse time-resolution, typically daily or sometimes monthly. With a few exceptions, mechanical recordings on paper rolls began in the first half of the 20th century, typically with ta of 1 h or 30 min. Digital registrations started only during the last three decades of the 20th century. This short period limits investigations that require long time-series of sub-daily rainfall data, e.g, analyses of the effects of climate change on short-duration (sub-hourly) heavy rainfall. In addition, in the areas with rainfall data characterized for many years by coarse time-resolutions, annual maximum rainfall depths of short duration can be potentially underestimated and their use would produce errors in the results of successive applications. Currently, only 50% of the stations provide useful data at any time-resolution, that practically means ta = 1 min. However, a significant reduction of these issues can be obtained through the information content of the present database. Finally, we suggest an integration of the database by including additional rain gauge networks to enhance its usefulness particularly in a comparative analysis of the effects of climate change on extreme rainfalls of short duration available in different locations.

[CAT] L’objectiu d’aquesta memòria és el disseny d’un producte que instal·lat en una coberta plana redirigeixi l’aigua de pluja per altre usos. El projecte s’ha focalitzat geogràficament a les zones urbanes de la costa mediterrània per la gran concentració d’habitants del que es deriva un alt consum d’aigua i una alta generació d’aigües residuals, efectes que podrien veure’s pal·liats per l’ús del producte proposat. Per ordenar el desenvolupament del projecte s’ha seguit la metodologia dels dos rombes o diamants S’ha recollit la informació meteorològica i climàtica necessària per demostrar la necessitat d’utilitzar mètodes d’estalvi d’aigua. S’ha descrit les característiques bàsiques del sistema de sanejament, tractament i contenció d’inundacions i s’ha pogut evidenciar que la captura d’aigua a l’àmbit urbà disminuiria notablement la càrrega sobre aquest sistema, minimitzant els abocament nocius als medis receptors. Per adequar el producte al seu lloc d’ús, s’ha descrit els aspectes més rellevants de les cobertes planes, les seves característiques constructives, els usos actuals i els que sembla que venen i s’ha comprovat aquesta compatibilitat. Guiats per la normativa constructiva i la específica per embornals, s’ha definit els requeriments de cabal, resistència físico-química i a l’embussament. A l’enquesta realitzada s’ha vist que existeix interès per l’estalvi d’aigua, que les campanyes de conscienciació afecten positivament aquesta percepció i que existeix interès i demanda per a solucions de recollida d’aigües pluvials. També ha servit per assignar els valors de rellevància a les potencials funcions, sent la durabilitat i el baix manteniment els més demandats. A partir de l’enquesta s’ha establert que el diàmetre màxim seria el mateix que el de la baixant. Ja en el disseny del producte, s’ha produït un prototip funcional que s’ha sotmès al test de cabal però que no ha assolit el mínim per a una correcta evacuació. S’ha proposat substituir el requeriment d’unes dimensions que facilitessin l’ús universal per l’ús d’un coll d’embornal més ample o adaptable a embornals ja instal·lats. Tot i el fracàs en el test de cabal, s’ha comprovat l’assoliment de totes les altres funcions proposades. Després de l’avaluació econòmica, tot i que a un preu elevat, el producte tindria possibilitats en aquest mercat. El producte podria suposar gran estalvi d’aigua, que dependria de la capacitat d’emmagatzematge i preu de l’aigua. En una coberta de 40m2 amb la capacitat d’emmagatzematge suficient i un preu de 99,95€, amb l’ús del producte proposat es podria aconseguir un estalvi de quasi 20m3 (entre 12 i 36€) per any. [ENG] The main purpose of this work is to end up designing a flat roof drain capable of keeping the rainwater from getting wasted and instead relocating it to a tank for other uses, saving drinking water. This project has been geographically centered around the Mediterranean coast of Spain due to its large population that carries a huge demand, and the chronic deficit of water of this region. So, it's the ideal region to install something like the proposed solution. The double diamonds methodology has been used to guide the designing process. Through the use of meteorological and climatic data and combined with the current sewage system, it's been made clear that a rainwater harvesting scheme would make a positive impact not just in water consume but in the sewage system, avoiding harmful dumping. To be able to design a product that is compatible with its place of use, a thorough analysis of building waterproofing techniques has been done. The study of current and future uses shows that this kind of product can work in combination with urban gardens, solar farms other types of uses. Construction and drain specific codes stablished severe restrictions to the product, to the extent that it made it impossible to comply. When asked about water conservation, people have shown interest in a responsible water use and in systems or products to harvest rainwater. This interviews also helped establishing reliability, low maintenance and energy efficiency as top priorities, leaving looks to as non-crucial. One of the key features of the product had to be that it had to fit in a nonexpanded drain hole. As for the actual design, after presenting some preliminary designs, one that puts the pump and sensor under the drain has been chosen and improved. A prototype of it has been made using rapid prototyping methods and has been tested, failing at draining enough water to comply with the code. After this, the diameter restriction has been replaced so the new idea is to adapt the pumping chamber to a conventional drain. On the other hand, this design fulfills now (or through a more developed software) all the functions required and has optional features that the consumer can chose or leave, saving money. When installed on a catching area of 40m2 and with enough tank space, the product can catch almost 20m3 per year, making it about the 40% of the per person year water use. After the cost analysis, the product can make financial sense, costing less than 100€, what amounts to between 12 to 36€ at essentially no running cost.

Quantitative precipitation estimation (QPE) through remote sensing has to take rain microstructure into consideration, because it influences the relationship between radar reflectivity Z and rain intensity R. For this reason, separate equations are used to estimate rain intensity of convective and stratiform rain types. Here, we investigate whether incorporating synoptic scale meteorology could yield further QPE improvements. Depending on large-scale weather types, variability in cloud condensation nuclei and the humidity content may lead to variation in rain microstructure. In a case study for Bavaria, we measured rain microstructure at ten locations with laser-based disdrometers, covering a combined 18,600 h of rain in a period of 36 months. Rain was classified on a temporal scale of one minute into convective and stratiform based on a machine learning model. Large-scale wind direction classes were on a daily scale to represent the synoptic weather types. Significant variations in rain microstructure parameters were evident not only for rain types, but also for wind direction classes. The main contrast was observed between westerly and easterly circulations, with the latter characterized by smaller average size of drops and a higher average concentration. This led to substantial variation in the parameters of the radar rain intensity retrieval equation Z–R. The effect of wind direction on Z–R parameters was more pronounced for stratiform than convective rain types. We conclude that building separate Z–R retrieval equations for regional wind direction classes should improve radar-based QPE, especially for stratiform rain events.

Els microplàstics són petites partícules que provenen de plàstics o productes plàstics més grans i que la seva presència en el nostre entorn genera un gran impacte negatiu. Actualment, aquests microplàstics ja es troben presents en el mar, en l’aire i en l’aigua. En aquest projecte s’ha realitzat un estudi en el qual s’ha quantificat la quantitat de micropartícules i microplàstics que es dipositen en el sòl de la ciutat de Terrassa. Per a poder fer-ho s’han avaluat diferents metodologies de treball i, a partir d’aquestes, s’ha dissenyat una metodologia per a poder obtenir mostres i poder extreure els microplàstics d’aquestes. Finalment, s’ha estudiat la influència de les condicions meteorològiques en la major o menor deposició de microplàstics. Microplastics are small particles that come from larger plastics or plastic products and whose presence in our environment generates a great negative impact. These microplastics are now present in the sea, in the air and in the water. In this project, a study has been carried out in which the amount of microparticles and microplastics that are deposited in of the city of Terrassa has been quantified. In order to do this, different working methodologies have been evaluated and, based on these, a methodology has been designed to be able to obtain samples and to be able to extract the microplastics from them. Finally, the influence of weather conditions on the greater or lesser deposition of microplastics has been studied.

Precipitation processes at windward and leeward sides of the mountains have been object of study for many decades. Instead, inner mountain valleys, where usually most mountain population lives, have received considerably less attention. This article examines precipitation processes during a winter field campaign in an inner valley of the Pyrenees (NE Spain) using, among other instruments, a K-band vertically pointing Doppler radar (Micro Rain Radar) and a laser-based optical disdrometer (Parsivel). A decoupling is found between the stalled air of the valley and the air of the free atmosphere above the mountain crest level, evidenced by an increase of turbulence and spectral width of precipitation particles. Wind shear layer may promote riming and aggregation of the ice and snow particles. Two main rainfall regimes are found during the campaign: (1) stratiform rainfall mostly produced by water vapour deposition processes, although sometimes riming and aggregation become important, and (2) weak convection with slight dominance of collision-coalescence processes. Precipitation characteristics at the bottom of the valley show typical continental features such as low Liquid Water Content, despite the valley is only about 100 km from the sea. This study demonstrates that inner valley may present distinct precipitation features with respect to windward and leeward precipitation. This work was funded by the Spanish Agencia Estatal de Investigación (AEI) and Fondo Europeo al Desarrollo Regional (FEDER) [grant numbers CGL2015-65627-C3-1-R, CGL2015-65627-C3-2-R, CGL2016-81828-REDT, RTI2018-098693-B-C32] the Water Research Institute (IdRA) of the University of Barcelona and the Generalitat de Catalunya through the ANTALP Research Group [grant number 2017 SGR 1102].

La pluja és el desencadenant més generalitzat i freqüent d'esllavissades al llarg del món i per tant els llindars de pluja són una eina essencial per a: 1) la predicció a escala local i/o regional de riscos naturals desencadenats per la pluja, i 2) la implementació de sistemes d'alerta primerenca. D'aquesta manera caracteritzar efectivament els patrons de pluja amb intensitat i/o duració suficient per a desencadenar esllavissades és molt important. Tot i això, establir llindars crítics d'aquestes pluges és complicat degut a la gran variabilitat de la pluja depenent l'estacionalitat, geografia i climatologia i la relació amb altres factors, sobretot antropogènics. Consegüentment, l'anàlisi dels paràmetres de les pluges amb potencial de generar esllavissades és un cas d'estudi fonamental tant en la detecció de riscos geològics derivats d'esllavissades i per l'eficient gestió dels plans d'emergència per enfrontar les crisis derivades d'aquests riscos, com ara per la comprensió i definició de nous valors llindars per ser comparats amb els episodis de pluja i identificar-los com a potencials o no de generar esllavissades. El desenvolupament del plugin Local Rainfall Analysis a partir de l'algoritme de l'anàlisi de pluges del mòdul de simulació d'esllavissades de la plataforma HEIMDALL desenvolupat per l'Institut Cartogràfic i Geològic de Catalunya (ICGC) permet la descripció i parametrització d'un o diversos episodis de pluja concrets en l'espai i el temps, per tal de determinar si aquesta ha set la causa i/o desencadenant d'una esllavissada. Aquesta anàlisi ajuda a la presa de decisions de l'equip del ICGC i proporciona informació sobre valors de pluja llindars a escala local per augmentar la precisió dels coneixements de valors llindars d'episodis de pluja amb potencial de desencadenar un episodi d'esllavissades i d'aquesta manera estudiar amb més coneixement les possibles situacions de risc i/o de crisi.

3. pdf files, with 1) Text (11Pags.); 2) Tabls. (5); 3) Figs. (4). The definitive version is available at: https://www.sciencedirect.com/science/journal/03783774, The aim of this research was to analyse the effect of rainfall intensity and slope on soil and nutrient losses by hydric erosion in soils with different hydrological characteristics. This research was carried out on soils collected from slopes with different land uses/covers (LU/LC) -forest, scrub, agricultural, afforested and barren land-, from a mountain area (Sierra de Santo Domingo in the South Pyrenean region), where intensive farming and land use changes including land abandonment and changes in soil cover have occurred. Soils were placed on erosion boxes (30 cm × 20 cm) and compacted to a bulk density similar to that measured in the field (slope values ranged between 10 and 20%). Soil properties such as organic matter content, soil texture and N and P contents were analysed (values used as concentration in the original soil). Soils were subjected to simulated rainfall with intensity values usually recorded in the area during storms. Runoff volumes were collected at 10 min intervals from the time that runoff was generated. The steady infiltration rate as well as the average runoff rates and soil losses were evaluated for each land use. In the runoff samples, sediment concentration and nutrients (N and P) were analysed using different aliquots. The comparative analysis of the results obtained under simulated rainfall in plots with soils from different land uses allowed determining the differences in contribution of each land use to soil and nutrient losses when they are subjected to similar rainfall intensities. The results showed that the maximum runoff rates were reached in agricultural soil and barren land after 40 min at low intensity and after about 20 min at high intensity. However, in soils under forest, scrub and afforestation, runoff rates were much lower for the same rainfall intensity and duration period. Soil sealing was the main factor reducing infiltration in the agricultural and in barren LU/LC soils, while in the other cases runoff was mainly produced after saturation. Soil losses were more than 10xtimes higher in barren land and in agricultural soils than in the other land uses. Nitrogen losses in agricultural soils were about 3 times higher than in forest, and scrub or in afforested LU/LC. Under high intensity rainfall, there was an enrichment ratio (ER) of nitrogen in the sediment in relation to the original soil, which was higher in scrub and agricultural lands (up to 1.33 and 1.32, respectively) than in the rest of land uses (1.1 on average). Phosphorous losses were mainly associated with soil particles and the land uses that gave rise to higher P losses was agricultural under any intensity, while P losses increased significantly in forest and afforested LU/LC at high intensity. The enrichment ratio (ER) was higher in agricultural soils (up to 1.82, increasing with intensity), forest and afforested LU/LC (1.33 and 1.16, respectively under high intensity) than in scrub (1.22) and barren lands (near 1). Information gained in this research can be of interest to manage mountain agroecosystems to limit N and P supply from headwaters to hydrological systems., This research is part of the project CGL2014-52986-R which was funded by the Spanish Ministry of Economy and Competitiveness.

[EN] The final objective of this analysis is to determine the most comprehensive and optimal solution for the stormwater management in the "Molí d'Animeta" Sector. It is based on an objective analysis of different types of networks, mixing the traditional approach with the most innovative of them. In relation to the latter, this work introduces the Sustainable Drainage Systems (SuDS), which seek to comply with the management of the quantity (volume and flow) of the water they collect, as in conventional systems. In addition, they also focus on achieving an acceptable level of runoff treatment to avoid negative impacts on the receiving environment, contributing to environmental and landscape improvement of the city and the life of its citizens. After designing each of them, considering physical and administrative boundary conditions, and following the specific design criteria according to their nature, they are checked and verified using the Infoworks CS computer tool, obtaining the hydraulic variables that will support this aspect to each solution. Then, other economic, social, environmental and energy factors will be added to the final comparison, using E2STORMED Decision Support Tool, chosen the proposal that, from a more holistic point of view, adapts better to specific design goals. The definition of a monitoring and maintenance plan is included to give a more complete and compact solution, being one of the fundamental pillars to preserve a good functioning of the system throughout its useful life and publicize its usefulness. Finally, the economic valuation of the adopted solution is carried out, in order to have a reference value in terms of the investment that would be involved in building the stormwater management system of the present study., [CA] El objecte final d'aquest estudi és determinar la solución més integral i òptima per a la gestió de les aigües pluvials del Sector "Molí d'Animeta". Es basa en l'anàlisi objectiu de diferents tipologies de xarxes, barrejant l'enfocament tradicional amb el més innovador. En relació amb aquest últim, s'introdueixen en aquest treball els Sistemes Urbans de Drenatge Sostenible (SUDS), els quals busquen complir amb la gestió de la quantitat (volum i cabal) de les aigües que recullen, tal com succeïx en els sistemes convencionals. A més, se centren en arribar a un nivell de tractament de l'escolament acceptable per no causar impactes negatius en el medi receptor, contribuint a millorar ambiental i paisatgísticament la ciutat i, amb això, la vida dels seus ciutadans. Després de dissenyar cadascuna d'elles, atenent les condicions de contorn físiques i administratives, i seguint els criteris de disseny especifics segons la seua naturalesa, es procedeix a la seua comprobació i verificació mitjançant la ferramenta informática Infoworks CS, obtenint les variables hidráuliques que donaran suport a cada solución. Posteriorment, s'afegiran altres factors d'aspecte econòmic, social, ambiental i energètic a la comparaciò final, que ha sigut posible gràcies a l'empleu de la ferramenta E2STORMED Decision Support Tool, inclinant la balança per aquella proposta que, des de un punt de vista mès holistic, s'adapte millor als objectius especifics del disseny. La definició d'un pla de monitorització i mantenimient s'inclou per a donar una soluciò mès completa i compacta, sent uns dels pilars fonamental per a preservar un bon funcionament del sistema al llarg de la seua vida útil i donar a conéixer la seua utilitat. Finalment, es du a terme la valoració econòmica de la solución adoptada, per a poder tener un valor de referéncia respecte a l'inversió que suposaria construir el sistema d'aigües pluvials dels present estudi., [ES] El objeto final de este estudio es determinar la solución más integral y óptima para la gestión de las aguas pluviales del Sector "Molí d'Animeta". Se basa en un análisis objetivo de diferentes tipologías de redes, mezclándose el enfoque tradicional con el más innovador. En relación con este último, se introducen en este trabajo los Sistemas Urbanos de Drenaje Sostenible (SUDS), los cuales buscan cumplir con la gestión de la cantidad (volumen y caudal) de las aguas que recogen, tal y como sucede en los sistemas convencionales, pero además se centran también en alcanzar un nivel de tratamiento de la escorrentía aceptable para no causar impactos negativos en el medio receptor, y contribuyendo a mejorar ambiental y paisajísticamente la ciudad y, con ello, la vida de sus ciudadanos. Tras diseñar cada una de ellas, atendiendo a las condiciones de contorno físicas y administrativas, y siguiendo los criterios de diseño específicos según su naturaleza, se procede a su comprobación y verificación mediante la herramienta informática Infoworks CS, obteniéndose las variables hidráulicas que respaldarán en este aspecto a cada solución. Posteriormente, se añadirán otros factores de tipo económico, social, ambiental y energético a la comparación final, posible gracias al empleo de la herramienta E2STORMED Decision Support Tool, decantándose la balanza por aquella propuesta que, desde un punto de vista más holístico, se adapte mejor a los objetivos específicos del diseño. La definición de un plan de monitorización y mantenimiento se incluye para dar una solución más completa y compacta, siendo uno de los pilares fundamentales para preservar un buen funcionamiento del sistema a lo largo de su vida útil y dar a conocer su utilidad. Finalmente, se lleva a cabo la valoración económica de la solución adoptada, para poder tener un valor de referencia en cuanto a la inversión que supondría construir el sistema de gestión de aguas pluviales del presente estudio.

[spa] Se presenta una aproximación al conocimiento actual y futuro del comportamiento de la lluvia como indicador de riesgo para la gestión de los recursos hídricos. Se hace especial hincapié en el ámbito mediterráneo y, concretamente, en la región de Cataluña situada en la cuenca occidental del Mediterráneo. Según el último informe sobre el estado del cambio climático (IPCC), se prevé para las próximas décadas un aumento de la irregularidad pluviométrica en las regiones de clima mediterráneo, tanto por un aumento de las sequías como de los episodios de lluvias torrenciales. En el caso concreto de Cataluña, en las décadas recientes se ha observado un desplazamiento de los episodios extremadamente torrenciales hacia el otoño tardío e invierno. Estos cambios en el comportamiento de la lluvia en el Mediterráneo pueden dar lugar a nuevos retos de gestión de los recursos hídricos y de prevención de los riesgos climáticos en el actual contexto de cambio climático, [eng] Herein we present an approach aimed at furthering our current and future knowledge of rainfall behaviour in order to provide a risk indicator for management of water resources. We emphasise the Mediterranean environment, specifically the region of Catalonia, located in the west of the Mediterranean Basin. According to the latest report upon the state of climate change (IPCC), an increase in rainfall variability is forecast for the next few decades in the Mediterranean climate regions, as a result of both increased droughts and torrential rainfall events. Specifically in Cataluña, extreme torrential events have been observed to be displaced to late autumn and winter. In the current context of climate change, these changes in rainfall behaviour patterns in the Mediterranean region can pose new challenges in the management of water resources and the prevention of climate risks.

Lovejoy and Schertzer (1990a) presented a statistical analysis of blotting paper observations of the (two-dimensional) spatial distribution of raindrop stains. They found empirical evidence for the fractal scaling behavior of raindrops in space, with potentially far-reaching implications for rainfall microphysics and radar meteorology. In particular, the fractal correlation dimensions determined from their blotting paper observations led them to conclude that "drops are (hierarchically) clustered" and that "inhomogeneity in rain is likely to extend down to millimeter scales". Confirming previously reported Monte Carlo simulations, we demonstrate analytically that the claims based on this analysis need to be reconsidered, as fractal correlation dimensions similar to the ones reported (i.e. smaller than the value of two expected for uniformly distributed raindrops) can result from instrumental artifacts (edge effects) in otherwise homogeneous Poissonian rainfall. Hence, the results of the blotting paper experiment are not statistically significant enough to reject the Poisson homogeneity hypothesis in favor of a fractal description of the discrete nature of rainfall. Our analysis is based on an analytical expression for the expected overlap area between a circle and a square, when the circle center is randomly (uniformly) distributed inside the square. The derived expression (πr2−8r3/3+r4/2, where r denotes the ratio between the circle radius and the side of the square) can be used as a reference curve against which to test the statistical significance of fractal correlation dimensions determined from spatial point patterns, such as those of raindrops and rainfall cells.

In this paper, we illustrate a new, simple and complementary ground-based methodology to retrieve the vertically resolved atmospheric precipitation intensity through a synergy between measurements from the National Aeronautics and Space Administration (NASA) Micropulse Lidar network (MPLNET), an analytical model solution and ground-based disdrometer measurements. The presented results are obtained at two mid-latitude MPLNET permanent observational sites, located respectively at NASA Goddard Space Flight Center, USA, and at the Universitat Politècnica de Catalunya, Barcelona, Spain. The methodology is suitable to be applied to existing and/or future lidar/ceilometer networks with the main objective of either providing near real-time (3 h latency) rainfall intensity measurements and/or to validate satellite missions, especially for critical light precipitation (

The study has obtained a classification of the synoptic patterns associated with a selection of extreme rain episodes registered in the Ebre Observatory between 1905 and 2003, showing a return period of not less than 10 years for any duration from 5 min to 24 h. These episodes had been previously classified in four rainfall intensity groups attending to their meteorological time scale. The synoptic patterns related to every group have been obtained applying a multivariable analysis to three atmospheric levels: sea-level pressure, temperature, and geopotential at 500 hPa. Usually, the synoptic patterns associated with intense rain in southern Catalonia are featured by low-pressure systems advecting warm and wet air from the Mediterranean Sea at the low levels of the troposphere. The configuration in the middle levels of the troposphere is dominated by negative anomalies of geopotential, indicating the presence of a low or a cold front, and temperature anomalies, promoting the destabilization of the atmosphere. These configurations promote the occurrence of severe convective events due to the difference of temperature between the low and medium levels of troposphere and the contribution of humidity in the lowest levels of the atmosphere.

For a few decades the local rainfall measurements are generally obtained by tipping bucket sensors, that allow to record each tipping time corresponding to a well-known rain depth. However, a considerable part of rainfall data to be used in the hydrological practice is available in aggregated form within constant time intervals. This can produce undesirable effects, like the underestimation of the annual maximum rainfall depth, Hd, associated with a given duration, d, that is the basic quantity in the development of rainfall depth-duration-frequency relationships. The errors in the evaluation of Hd from data characterized by a coarse temporal aggregation, ta, and a procedure to reduce the non-homogeneity of the Hd series are here investigated. Our results show that for ta = 1 min the underestimation is practically negligible, whereas for larger temporal aggregations with d = ta the error in a single Hd can reach values up to 50% and in a series of Hd in the average up to 17%. Relationships between the non-dimensional ratio ta/d and the average underestimation of Hd, derived through continuous rainfall data observed in many stations of Central Italy, are presented to overcome this issue. These equations allow to improve the Hd estimates and the associated depth-duration-frequency curves at least in areas with similar climatic conditions. The effect of the correction of the Hd series on the rainfall depth-duration-frequency curves is quantified. Our results indicate that the improvements obtained by the proposed procedure are of the order of 10%.

[ES] En este trabajo, en la introducción se hace una exposición sobre qué son los SUDS (Sistemas Urbanos de Drenaje Sostenible) y qué tipos hay. Se hace una relación de los fundamentos básicos que persiguen integrar los SUDS dentro de un entorno urbano y se hace una concisa explicación de cada uno de ellos. A continuación, se da una justificación del estudio que estoy realizando, mencionando la problemática que sufre el término municipal de Moncada. Se prosigue nombrando los objetivos que quiero alcanzar con este trabajo, tanto el objetivo principal, como los secundarios. En el siguiente apartado se habla extensamente sobre el área de estudio: Moncada. En se trata su geografía, climatología, geología e hidrogeología, vegetación, fauna y ecosistemas. A continuación, se pasa a describir la problemática de drenaje existente zonificando el casco urbano de Moncada en sectores. En este apartado es muy importante el uso de imágenes y vistas del satélite para mayor comprensión de dicha problemática. Una vez descrita la problemática de Moncada, se habla de los tipos de SUDS que se van a emplear, explicándolos más detenidamente sobre qué es lo que pueden aportar. Terminado este apartado se llega a unos de los puntos más importantes del trabajo, las propuestas de diseño a soluciones de drenaje sostenible. Para tratar estas soluciones y abarcar toda la problemática todo ello se ha estructurado en un sistema de prioridades de tres niveles., [CA] En este treball, en la introducció es fa una exposició sobre què són els SUDS (Sistemes Urbans de Drenatge Sostenible) i quins tipus hi ha. Es fa una relació dels fonaments bàsics que perseguixen integrar els SUDS dins d'un entorn urbà i es fa una concisa explicació de cada un d'ells. A continuació, es dóna una justificació de l'estudi que estic realitzant, mencionant la problemàtica que patix el terme municipal de Moncada. Es prosseguix anomenant els objectius que vull aconseguir amb este treball, tant l'objectiu principal, com els secundaris. En el següent apartat es parla extensament sobre l'àrea d'estudi: Moncada. En es tracta la seua geografia, climatologia, geologia i hidrogeologia, vegetació, fauna i ecosistemes. A continuació, es passa a descriure la problemàtica de drenatge existent zonificando el nucli urbà de Moncada en sectors. En este apartat és molt important l'ús d'imatges i vistes del satèl·lit per a major comprensió de dita problemàtica. Una vegada descrita la problemàtica de Moncada, es parla dels tipus de SUDS que es van a emprar, explicant-los més detingudament sobre què és el que poden aportar. Acabat este apartat s'arriba a uns dels punts més importants del treball, les propostes de disseny a solucions de drenatge sostenible. Per a tractar estes solucions i comprendre tota la problemàtica tot això s'ha estructurat en un sistema de prioritats de tres nivells., [EN] In this paper, the introduction makes an exposition about what are the SUDS (Urban Systems of Sustainable Drainage) and what types there are. It is made a list of the basic foundations that seek to integrate the SUDS within an urban environment and a concise explanation of each of them is made. Next, a justification of the study that I am realizing is given, mentioning the problematic that undergoes the municipal term of Moncada. It continues by naming the objectives that I want to achieve with this work, both the main objective and the secondary objectives. The following section deals extensively with the area of study: Moncada. In its geography, climatology, geology and hydrogeology, vegetation, fauna and ecosystems. Then, we describe the problem of drainage existing zoning the town of Moncada in sectors. In this section is very important the use of images and views of the satellite for a better understanding of this problem. Once the problem of Moncada has been described, the types of SUDS to be used are discussed, explaining them more in detail about what they can contribute. Finished this section you will reach some of the most important points of the work, the design proposals to sustainable drainage solutions. In order to deal with these solutions and to cover all the problems, all this has been structured in a system of priorities of three levels.

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.