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60 Pags., 8 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/01436228 ; Understanding, monitoring and mitigating drought is a very difficult task as a consequence of the intrinsic nature of the phenomenon. In addition, assessing the impact of drought on ecosystems and societies is also a complex task, because the same drought severity may have different consequences in different regions and systems due to the underlying vulnerabilities. New technologies based on geospatial information are available to determine the risk and vulnerability of a system to a drought and to develop monitoring and early warning systems based on real-time information to support decision making. To improve drought preparedness and mitigation, geospatial datasets based on climate information, Earth Observation Systems and statistical and dynamical modelling methodologies can make a noticeably difference in mitigating drought impacts in Africa. In this article we illustrate how the development of drought information systems based on geospatial technology, that combines static and real-time information, could improve the possibilities of drought mitigation in Africa. We stress that it is necessary to go beyond past attempts to manage drought risk based on a reactive crisis-response approach, by promoting drought mitigation and preparedness at the national and regional levels. For this purpose the development of drought information tools is fundamental for the implementation of drought management plans and to support real-time decision-making. ; This work has been supported by the research projects CGL2006-11619/HID, CGL2008-01189/BTE, CGL2011-27574-CO2-02, CGL2011-27753-CO2-01 and CGL2011-27536 financed by the Spanish Commission of Science and Technology and FEDER, EUROGEOSS (FP7-ENV-2008-1-226487), AfroMaison (Grant agreement no 266379) and ACQWA (Grant Agreement n°212250) financed by the 7th Framework Programme of the European Commission, "La nieve en el Pirineo Aragonés y su respuesta a la variabilidad climática" and "Efecto de los escenarios de cambio climático sobre la hidrología superficial y la gestión de embalses del Pirineo Aragonés" financed by "Obra Social La Caixa" and the Aragón Government and Influencia del cambio climático en el turismo de nieve. CTTP01/10, Financed by the Comisión de Trabajo de los Pirineos. ; Peer reviewed

11 Pags.- 1 Tabl.- 4 Figs. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. ; We present a long-term assessment of precipitation trends in Southwestern Europe (1850–2018) using data from multiple sources, including observations, gridded datasets and global climate model experiments. Contrary to previous investigations based on shorter records, we demonstrate, using new long-term, quality controlled precipitation series, the lack of statistically significant long-term decreasing trends in precipitation for the region. Rather, significant trends were mostly found for shorter periods, highlighting the prevalence of interdecadal and interannual variability at these time-scales. Global climate model outputs from three CMIP experiments are evaluated for periods concurrent with observations. Both the CMIP3 and CMIP5 ensembles show precipitation decline, with only CMIP6 showing agreement with long term trends in observations. However, for both CMIP3 and CMIP5 large interannual and internal variability among ensemble members makes it difficult to identify a trend that is statistically different from observations. Across both observations and models, our results make it difficult to associate any declining trends in precipitation in Southwestern Europe to anthropogenic forcing at this stage. ; This work was supported by the research projects CGL2017-82216-R, CGL2017-83866-C3-3-R and PCI2019-103631, financed by the Spanish Commission of Science and Technology and FEDER; CROSSDRO project financed by the AXIS (Assessment of Cross(X)—sectoral climate Impacts and pathways for Sustainable transformation), JPI-Climate co-funded call of the European Commission and INDECIS which is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Union (Grant 690462). Dhais Peña-Angulo received a 'Juan de la Cierva' postdoctoral contract (FJCI-2017-33652 Spanish Ministry of Economy and Competitiveness, MEC). Conor Murphy was supported by the Irish Environmental Protection Agency (Grant Nos. 2019-CCRP-MS.60). Marco Turco has received funding from the Spanish Ministry of Science, Innovation and Universities through the project PREDFIRE (RTI2018-099711-J-I00), which is co-financed with the European Regional Development Fund (ERDF/FEDER). ; Peer reviewed

20 Pags.,- 13 Figs.- 3 Tabls. Supplementary data associated with this article can be found, in the online version. © 2017 The Author(s). Published by Elsevier B.V. This is an open access article under the license Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) ; Study region: The Segre basin (northeastern Spain). Study focus: The Segre basin is extensively regulated, through a dense network of dams, during the second half of the 20th century. This study assessed the impact of river regulation on the evolution of hydroclimatological extreme events across the basin during the past six decades (1950–2013). We assessed whether the occurrence of floods and hydrological droughts has changed, and whether these changes have differed spatially between the headwaters and lower areas ofthe basin. For this purpose, we employed a set of hydroclimatological indices in order to quantify the evolution of the amount as well as the frequency of quantiles of high precipitation and flood events. Changes in these variables were assessed by means of the nonparametric Mann–Kendall Tau coefficient. New hydrological insights: Results reveal a general reduction in the occurrence of extreme precipitation events in the Segre basin from 1950 to 2013, which corresponded to a general reduction in high flows measured at various gauged stations across the basin. While this study demonstrates spatial differences in the decrease of streamflow between the headwaters and the lower parts of the basin, mainly associated with changes in river regulation, there was no reduction in the frequency of the extraordinary floods. Changes in water management practices in the basin have significantly impacted the frequency, duration, and severity of hydrological droughts downstream of the main dams, as a consequence of the intense water regulation to meet water demands for irrigation and livestock farms. Nonetheless, the hydrological response of the headwaters to these droughts differed markedly from that of the lower areas of the basin. ; This work was supported by the research project PCIN-2015-220, CGL2014-52135-C03-01, Red de variabilidad y cambioclimático RECLIM (CGL2014-517221- REDT) financed by the Spanish Commission of Science and Technology and FEDER, "LIFE12 ENV/ES/000536-Demonstration and validation of innovative methodology for regional climate change adaptation in the Mediterranean area (LIFE MEDACC)" financed by the LIFE programme of the European Commission and IMDROFLOOD financed by the Water Works 2014 cofunded call of the European Commission. Marina Peña-Gallardo and Esteban Alonso-González were granted by the Spanish Ministry of Economy and Competitiveness; Natalia Martin-Hernandez was supported by a doctoral grant by the Aragón Regional Government; and Miquel Tomas-Burguera was supported by a doctoral grant by el Ministerio de Educación, Cultura y Deporte. Arturo Sanchez-Lorenzo was supported by a postdoctoral fellowship JCI-2012-12508 financed by the Spanish Ministry of Economy and Competitiveness. ; Peer reviewed

48 Pags.- 1 Tabl.- 18 Figs. The definitive version is available at: http://link.springer.com/journal/382 ; In this study, we analyzed the influence of El Niño–Southern Oscillation (ENSO) on the spatio-temporal variability of droughts in Ecuador for a 48-year period (1965–2012). Droughts were quantified from 22 high-quality and homogenized time series of precipitation and air temperature by means of the Standardized Precipitation Evapotranspiration Index. In addition, the propagation of two different ENSO indices (El Niño 3.4 and El Niño 1 + 2 indices) and other atmospheric circulation processes (e.g., vertical velocity) on different time-scales of drought severity were investigated. The results showed a very complex influence of ENSO on drought behavior across Ecuador, with two regional patterns in the evolution of droughts: (1) the Andean chain with no changes in drought severity, and (2) the Western plains with less severe and frequent droughts. We also detected that drought variability in the Andes mountains is explained by the El Niño 3.4 index [sea surface temperature (SST) anomalies in the central Pacific], whereas the Western plains are much more driven by El Niño 1 + 2 index (SST anomalies in the eastern Pacific). Moreover, it was also observed that El Niño and La Niña phases enhance droughts in the Andes and Western plains regions, respectively. The results of this work could be crucial for predicting and monitoring drought variability and intensity in Ecuador. ; This work was supported by the EPhysLab (UVIGO-CSIC Associated Unit) and the research projects I-COOP H2O 2013CD0006: "Test multisectorial y actividades demostrativa sobre el potencial desarrollo de sistemas de monitorización de sequías en tiempo real en la región del oeste de Sudamérica" financed by the Spanish National Research Council, CGL2011-27574-CO2-02, CGL2014-52135-C03-01 and Red de variabilidad y cambio climático RECLIM (CGL2014-517221-REDT), financed by the Spanish Commission of Science and Technology and FEDER, and "LIFE12 ENV/ES/000536-Demonstration and validation of innovative methodology for regional climate change adaptation in the Mediterranean area (LIFE MEDACC)" financed by the LIFE programme of the European Commission. Cesar Azorin-Molina was supported by the JCI-2011-10263 Grant. Arturo Sanchez-Lorenzo was supported by the JCI-2012-12508 Grant. Miquel Tomas-Burguera was supported by a doctoral grant by the Ministry of Economy and Competitiveness and Natalia Martin-Hernandez was supported by a doctoral grant by the Aragón Regional Government. E. Aguilar was funded by the Grant CCI-009-ATN/OC-12439-RG-2012 from the Banco Iberoamericano de Desarrollo. ; Peer reviewed

8 Pags.- 3 Figs. © Te Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. ; Climate proxy data are required for improved understanding of climate variability and change in the pre-instrumental period. We present the first international initiative to compile and share information on pro pluvia rogation ceremonies, which is a well-studied proxy of agricultural drought. Currently, the database has more than 3500 dates of celebration of rogation ceremonies, providing information for 153 locations across 11 countries spanning the period from 1333 to 1949. This product provides data for better understanding of the pre-instrumental drought variability, validating natural proxies and model simulations, and multi-proxy rainfall reconstructions, amongst other climatic exercises. The database is freely available and can be easily accessed and visualized via http://inpro.unizar.es/. ; This work was supported by the research projects CGL2017-82216-R, PCI2019-103631 and PID2019- 108589RA-100 financed by the Spanish Commission of Science and Technology and FEDER; CROSSDRO project fnanced by the AXIS (Assessment of Cross (X)- sectoral climate Impacts and pathways for Sustainable transformation), and JPI-Climate co-funded call of the European Commission and INDECIS which is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Union (Grant 690462). Te research of Nieves Bravo-Paredes has been supported by the predoctoral fellowship PRE2018-084897 from Agencia Estatal de Investigación (Ministerio de Ciencia, Innovación y Universidades) of the Spanish Government. Te Portuguese data search stems partly from the project KlimHist, fnanced by FCT (PTDC/AAC–CLI/119078/2010). ; Peer reviewed