Prediction, disaggregation and climate change in precipitation for hydrological applications

RESUMEN: La presente tesis trata la precipitación en su dimensión temporal. En ella se investigan nuevas metodologías y se desarrollan nuevas herramientas que sirven para tratar las disciplinas de la predicción temporal de la precipitación, de la desagregación temporal, y de los efectos del cambio climático en la precipitación. Los resultados alcanzados son de gran utilidad para diferentes tipos de aplicaciones hidrológicas. Como por ejemplo, para aquellas en las que sea necesario conocer la precipitación en el pasado o en el futuro, en un contexto de cambio climático, con el objetivo de gestionar los recursos hídricos de una cuenca; también en aquellas situaciones en las que se requiera implementar un sistema operacional de corto plazo que sirva para predecir el riesgo asociado a determinados eventos extremos de precipitación; o en aquellos casos en los que no se disponga de datos de precipitación a una resolución temporal subdiaria, y no obstante sean requeridos para estudios de inundación o para diseñar el drenaje urbano de una ciudad.ABSTRACT: This thesis deals with the precipitation in its temporal dimension. In it, new methodologies are investigated, and new tools are developed, that serve to deal with the following disciplines: rainfall prediction, rainfall disaggregation, and rainfall and climate change. The results achieved here are very useful for different types of hydrological applications. As for example, for those in which it is necessary to know the precipitation in the past or in the future, in a context of climate change, with the objective of managing the water resources of a basin; also in those situations in which a short-term operational is required to evaluate the risk associated with certain extreme precipitation events; or in those cases in which rainfall data is not available at sub-daily temporal aggregation, and however are required for flood studies or to design the urban drainage of a city.Gracias a la Agencia Estatal de Investigación (AEI) del Ministerio de Economía, Industria y Competitividad, y a la European Regional Development Fund (ERDF) por la financiación recibida a través de subvención BIA2016-78397-P (AEI/FEDER,UE)

Subdaily Rainfall Estimation through Daily Rainfall Downscaling Using Random Forests in Spain

Subdaily rainfall data, though essential for applications in many fields, is not as readily available as daily rainfall data. In this work, regression approaches that use atmospheric data and daily rainfall statistics as predictors are evaluated to downscale daily-to-subdaily rainfall statistics on more than 700 hourly rain gauges in Spain. We propose a new approach based on machine learning techniques that improves the downscaling skill of previous methodologies. Results are grouped by climate types (following the Köppen?Geiger classification) to investigate possible missing explanatory variables in the analysis. The methodology is then used to improve the ability of Poisson cluster models to simulate hourly rainfall series that mimic the statistical behavior of the observed ones. This approach can be applied for the study of extreme events and for daily-to-subdaily precipitation disaggregation in any location of Spain where daily rainfall data are available.This research was funded by “Agencia Estatal de Investigación (AEI)” from the Spanish Ministry of Economy, Industry and Competitiveness, and the European Regional Development Fund (ERDF) (Grant Number BIA2016-78397-P (AEI/FEDER, UE); and by Project INDECIS, which is part of ERA4CS, an ERA-NET initiated by JPIClimate and funded by FORMAS(SE), DLR (DE), BMWFW(AT), IFD(DK), MINECO (ES), ANR (FR) with co-funding by the European Union (Grant Number 690462

Downscaling from daily to subdaily rainfall through regression based on large-scale atmospheric variables

Urban hydrology studies usually require observed rainfall information of high temporal resolution (1 h or less) (Smith et al., 2007) for derived flood frequency analysis, infrastructure design or risk assessments (Arnbjerg-Nielsen et al., 2013). However, rainfall stations with hourly resolution are more sparse than daily rainfall stations, and in most studies, no rainfall information is available at subdaily resolution. There are different solutions to address the problem of rainfall temporal downscaling such as the point process theory (Rodriguez-Iturbe et al., 1987) or assuming some temporal scaling behavior of the rainfall statistics (Marani and Zanetti, 2007). However, while in the first approach it is advisable to include the subdaily rainfall properties in the calibration process to improve the quality of the simulated synthetic subdaily rainfall series (Cowpertwait et al 1996), the second one is only appropriate for specific rainfall regimes or climates. The goal of the present work is to provide subdaily rainfall series at locations where only daily rainfall series are available. Our work extends the methodology carried out by Beuchat et al., 2011 to other climatic regimes. The methodology is based on seeking relationships between target subdaily rainfall statistics and available predictors, including daily rainfall statistics and large-scale atmospheric variables. Then the predicted subdaily statistics are included in the calibration process to improve the skill of the point process models to simulate synthetic subdaily series. As a result, we validate the skill of the methodology in other climatic regimes and also, in order to improve the results, we tests different regression methods and reanalysis databases. The results show the power of the methodology to simulate synthetic subdaily rainfall series.The authors would like to thank “Agencia Estatal de Investigación (AEI)‘’ from the Spanish Ministry of Economy, Industry and Competitiveness, and the European Regional Development Fund (ERDF) for the funding provided through grant BIA2016-78397-P (AEI/FEDER, UE) for the development of this work

Nuevo índice para evaluar anomalías de elementos traza en suelos: el caso del SE español

In this work, an index is established to detect anomalies in trace elements in the soil. This index, which relates the total concentration of each element with the regional geochemical background value of the element considered, was defined by studying the levels of trace elements from different soils located in SE Spain. In the area, a previous screening of trace elements detected seven zones with anomalies and revealed two conflictive areas: Sierra Gador and Cabo de Gata. In each zone, a second sampling was undertaken at two different depths (0-20 cm and 20-40 cm). The results indicate that the main anomalies were due to arsenic (As), lead (Pb), and zinc (Zn). In Sierra Gador Pb was the element that registered the highest rate of enrichment with respect to the regional geochemical background, reaching values up to 270-fold higher in some samples. In this zone, more than 50% of the samples were anomalous in any of the trace elements studied (higher than regional geochemical background). In Cabo de Gata, As concentration was higher than the geochemical background in more than 40% of the samples; meanwhile Pb concentration was higher in 50% of the samples.En este trabajo establecemos un índice para detectar anomalías en el contenido de elementos traza en suelos. Este índice relaciona el contenido total de cada elemento traza con el fondo geoquímico regional, definido mediante el estudio de los niveles de elementos traza en diferentes suelos localizados en el sureste español. En un primer estudio sobre niveles de elementos traza en suelos del área de estudio detectaron siete zonas con anomalías, de las cuales dos fueron consideradas conflictivas: Sierra de Gádor y Cabo de Gata. En cada una de estas dos zonas se realizó un segundo estudio más exhaustivo a dos niveles de profundidad (0-20 y 20-40 cm). Los resultados indican que las principales anomalías correspondes a los niveles de As, Pb y Zn. En Sierra de Gádor el Pb es el elemento que presenta una mayor tasa de enriquecimiento con respecto al fondo geoquímico regional, con valores puntuales que lo superan hasta 270 veces. También en esta zona más del 50% de las muestras presentan anomalías en alguno de los elementos analizados. En Cabo de Gata el As supera el fondo geoquímico regional en más del 40% de las muestras; mientras que el Pb lo supera en el 50% de las muestras.This study has been made possible by the research Project no. 1550 of the Regional Environmental Department of the Andalusian Government

Coastal flooding risk associated to tropical cyclones in a changing climate. Application to Port of Spain (Trinidad and Tobago)

The aim of this paper is to provide a methodology to assess flooding risk associated to the combination of extreme flooding levels driven by Tropical Cyclone (TCs) and relative sea level rise (RSLR). The approach is based on the risk conceptual framework where the hazard, exposure, and vulnerability are defined and combined to address flooding socioeconomic consequences in Port of Spain for present and future climate (RCP8.5 in 2050). Hazard and flooding impact are assessed using a combination of statistical methods and dynamical simulations, together with a high resolution Digital Elevation Model (DEM). Combining flooding maps, exposure databases and vulnerability damage functions we have evaluated socioeconomic consequences in terms of affected population and economic damage. Besides, we have quantified the uncertainty in the results coming from the sea level rise projections and vulnerability information. The application of the methodology indicates increasing flooding threat for the future climate that could exacerbate economic losses in case of inaction. The expected annual damage (EAD) in present climate is 12.24 MUSD while in 2050 it will reach 15.22 [14.88- 15.67] MUSD.This paper comes out from the project “Port of Spain Probabilistic Hazard and Vulnerability Assessment based on Climate Change Projections” funded by the Inter-American Development Bank (IDB). We acknowledge the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modelling groups for producing and making available their model output

Climate change impacts on the water resources of Andean countries

RESUMEN: Latinoamérica presenta una alta disponibilidad y un elevado volumen de recurso hídrico. Este hecho, combinado con una abrupta topografía, permite generar importantes aprovechamientos hidroeléctricos con estructuras relativamente reducidas, lo que ha hecho proliferar este tipo de explotaciones. De manera reciente, sin embargo, ha comenzado a manifestarse inquietud respecto a los efectos que el cambio climático pueda tener sobre las centrales hidroeléctricas, y cómo esto pueda afectar a la disponibilidad y distribución de energía eléctrica en los distintos países. En el presente trabajo presentamos la metodología y principales resultados obtenidos en el estudio Vulnerabilidad al cambio climático y medidas de adaptación de sistemas hidroeléctricos en países andinos que ha cubierto los sistemas hidroeléctricos de Bolivia, Colombia, Ecuador y Perú. Focalizaremos nuestros esfuerzos en el análisis del recurso hídrico, paso previo al análisis de la evolución del recurso hidroeléctrico, a nivel regional, donde se han generado unas bases de datos homogéneas para toda el área de estudio mediante reconstrucción temporal y espacial, haciendo uso de técnicas de krigeado. También se ha procedido a homogeneizar la información sobre tipos de suelo y usos del suelo. La hidrología se ha resuelto con el modelo hidrológico semidistribuido VIC. Se ha analizado el periodo histórico 1980-2010, y se han generado proyecciones de cambio climático para el corto plazo (2011-2040), el medio plazo (2041-2070) y el largo plazo (2071-2100) para los escenarios RCP4.5 y RCP8.5 utilizados en el 5° informe del IPCC (Panel Intergubernamental para el Cambio Climático). Se ha tenido en cuenta además la posible evolución socioeconómica y su impacto sobre los usos del suelo.ABSTRACT: Latin America is characterized by a highly available, large amount of water resources. This fact, combined with an abrupt topography allows the creation of important hydropower stations with relatively small structures, what has fostered this kind of infrastructures. Recently, however, some worries have started to appear related to the effects that climate change may have on hydropower stations, and how these effects may change the spatial distribution of energy generation in the region. In this work, we present a methodology and the main results obtained in the study Climate change vulnerability and adaptation measures of hydropower stations in Andean countries that has studied the hydropower systems of Bolivia, Colombia, Ecuador and Peru. The main focus of this work is on the regional analysis of the water resources, a previous step to the analysis of the evolution of hydropower resources, where homogeneous databases of hydroclimatic variables have been generated for the whole study area, making use of spatio-temporal reconstruction through Kriging. Land use and soil type information has also been homogenized for the whole study area. Hydrology has been resolved with the semi distributed hydrologic model VIC. We have analyzed the historic period 1980-2010 and have e ISSN: 1886-4996 ISSN: 1134-2196220 del Jesus et al. | Efectos del cambio climático en el recurso hídrico de los países andinos Ingeniería del Agua | 24.4 | 2020 generated climate change projections for the short term (2011-2040), the medium term (2041-2070) and the long term (2071-2100) for scenarios RCP4.5 and RCP8.5 of the 5th Assessment Report of the IPCC. We have also considered the socio-economic evolution and its impact on land use.Los autores agradecen al Banco Interamericano de Desarrollo (BID) y a la Organización Latinoamericana de la Energía (OLADE) la financiación aportada para la realización del estudio. Manuel del Jesus, Salvador Navas y Javier Díez-Sierra agradecen, además, a la Agencia Estatal de Investigación (AEI) y al Fondo Europeo de Desarrollo Regional (FEDER) la financiación aportada a través del proyecto BIA2016-78397-P (AEI/FEDER, UE)

Real-life outcomes in biotypes of psychotic disorders based on neurocognitive performance

Producción CientíficaAiming at discerning potential biotypes within the psychotic syndrome, we have recently reported the possible existence of two clusters or biotypes across schizophrenia and bipolar disorder characterized by their cognitive performance using the Brief Assessment of Cognition in Schizophrenia (BACS) instrument and validated with independent biological and clinical indexes (Fernández-Linsenbarth et al. in Schizophr Res 229:102–111, 2021). In this previous work, the group with larger cognitive deficits (N = 93, including 69 chronic schizophrenia, 17 first episodes (FE) of schizophrenia and 7 bipolar disorder patients) showed smaller thalamus and hippocampus volume and hyper-synchronic electroencephalogram than the group with milder deficits (N = 105, including 58 chronic schizophrenia, 25 FE and 22 bipolar disorder patients). We predicted that if these biotypes indeed corresponded to different cognitive and biological substrates, their adaptation to real life would be different. To this end, in the present work we have followed up the patients’ population included in that work at 1st and 3rd years after the date of inclusion in the 2021 study and we report on the statistical comparisons of each clinical and real-life outcomes between them. The first cluster, with larger cognitive deficits and more severe biological alterations, showed during that period a decreased capacity for job tenure (1st and 3rd years), more admissions to a psychiatric ward (1st year) and a higher likelihood for quitting psychiatric follow-up (3rd year). Patients in the second cluster, with moderate cognitive deficits, were less compliant with prescribed treatment at the 3rd year. The differences in real-life outcomes may give additional external validity to that yielded by biological measurements to the described biotypes based on neurocognition.Instituto de Salud Carlos III (grant ID PI18/00178)Dirección Regional de Salud de Castilla y León (grant ID GRS 2121/A/2020)Junta de Castilla y León - predoctoral grants from the Consejería de Educación and the European Social Fund (grant IDs VA-183-18 to IFL and VA- 223-19 to RMBRS)Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

Functional network properties in schizophrenia and bipolar disorder assessed with high-density electroencephalography

Background: The study of the cortical functional network properties in schizophrenia (SZ) may benefit from the use of graph theory parameters applied to high-density electroencephalography (EEG). Connectivity Strength (CS) assesses global synchrony of the network, and Shannon Graph Complexity (SGC) summarizes the network distribution of link weights and allows distinguishing between primary and secondary pathways. Their joint use may help in understanding the underpinnings of the functional network hyperactivation and task-related hypomodulation previously described in psychoses. Methods: We used 64-sensor EEG recordings during a P300 oddball task in 128 SZ patients (96 chronic, CR, and 32 first episodes, FE), as well as 46 bipolar disorder (BD) patients, and 92 healthy controls (HC). Pre-stimulus and modulation (task-response minus pre-stimulus windows values) of CS and SGC were assessed in the theta band (4–8 Hz) and the broadband (4–70 Hz). Results: Compared to HC, SZ patients (CR and FE) showed significantly higher pre-stimulus CS values in the broadband, and both SZ and BD patients showed lower theta-band CS modulation. SGC modulation values, both theta-band and broadband, were also abnormally reduced in CR patients. Statistically significant relationships were found in the theta band between SGC modulation and both CS pre-stimulus and modulation values in patients. CS altered measures in patients were additionally related to their cognitive outcome and negative symptoms. A primary role of antipsychotics in these results was ruled out. Conclusions: Our results linking SGC and CS alterations in psychotic patients supported a hyperactive and hypomodulatory network mainly involving connections in secondary pathways