Downstream-migrating antidunes in sand, gravel and sand-gravel mixtures

River hydrodynamicsBed roughness and flow resistanc

Influences of synoptic situation and teleconnections on fog-water collection in the Mediterranean Iberian Peninsula, 2003-2012

Fog-water collection has been widely analysed for its quantification and potential uses; however, there are few studies assessing the synoptic conditions and largescale teleconnection patterns that affect its occurrence. Focusing on the Mediterranean Iberian Peninsula, this work aims to analyse the synoptic patterns, both at surface level and 850 hPa geopotential height, that most likely to favour fogwater collection, and to quantify the relationship between fog-water collection and the NAOi (North Atlantic Oscillation index), MOi (Mediterranean Oscillation index) as well as WeMOi (Western Mediterranean Oscillation index) teleconnection patterns. For this purpose, daily fog-water observations from a dense network of 23 fog-water collectors located along the Mediterranean Iberian Peninsula for 2003-2012 were analysed in relation to synoptic patterns and the threeteleconnection indices. The major findings are: (a) The most favourable synoptic patterns for fog-water collection are maritime advections carrying humidity from the Mediterranean basin, and cyclonic circulations, whereas anti-cyclonic situations generally led to large number of foggy days with low fog-collection rates. (b) In terms of winds at 850 hPa, the most favourable low-level flows for fogwater collection are associated with strong winds (>5.1 m s−1) from theMediterranean. Atlantic winds generally cause a greater number of fog days than Mediterranean winds, with less fog-water collection rates. (c) WeMOi has the greatest influence on fog-water collection, mainly during winter and spring months, with statistically significant negative relationships for most of the stations. MOi also shows a great influence, with a large number of statistically significant negative correlations, mainly during the same months as WeMOi. Lastly, NAOi presented the lowest and no significant negative correlations with fog-water collection

Incision and width changes caused by dam removal. Experiments and data analysis

River morphodynamics and sediment transportRiver morphology and morphodynamic

A uniform family of tissue P systems with cell division solving 3-COL in a linear time

Several examples of the efficiency of cell-like P systems regarding the solution of NPcomplete problems in polynomial time can be found in the literature(obviously, trading space for time). Recently, different new models of tissue-like P systems have received much attention from the scientific community. In this paper we present a linear-time solution to an NP-complete problem from graph theory, the 3-coloring problem, and we discuss the suitability of tissue-like P systems as a framework to address the efficient solution to intractable problems.Ministerio de Educación y Ciencia TIN2005-09345-C04-01Junta de Andalucía TIC-58

A linear-time tissue P system based solution for the 3-coloring problem

In the literature, several examples of the efficiency of cell-like P systems regarding the solution of NPcomplete problems in polynomial time can be found (obviously, trading space for time). Recently, different new models of tissue-like P systems have received important attention from the scientific community. In this paper we present a linear-time solution to an NP-complete problem from graph theory, the 3–coloring problem, and we discuss the suitability of tissue-like P systems as a framework to address the efficient solution to intractable problems.Ministerio de Educación y Ciencia TIN2005-09345-C04-01Junta de Andalucía TIC-58

A component-based approximation for trend detection of intense rainfall in the Spanish Mediterranean coast

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)

Incisión, erosión transitoria y formas de fondo en los tramos medio y bajo del río Tordera

[ES] Se presenta en este trabajo los datos de campo y análisis que prueban el comportamiento dinámico del río Tordera. El aspecto más llamativo es el descenso general (incisión) del cauce del río, del orden de 3m y a lo largo de unos 15 km, en los últimos 40 años. Se muestra con datos de campo que la erosión general transitoria del cauce arenoso puede ser del orden de metros y que el lecho presenta grandes dunas.Martín Vide, JP.; Batalla, RJ.; Roca I Collell, M.; Rovira, A.; Andreatta, A. (2005). Incisión, erosión transitoria y formas de fondo en los tramos medio y bajo del río Tordera. Ingeniería del agua. 12(1):53-62. https://doi.org/10.4995/ia.2005.2551OJS5362121Ackers, P., White, W.R., Perkins, J.A., Harrison, J.M. (1978) "Weirs and flumes for flow measurement". John Wiley and sons, Chichester.Batalla, R.J. (1997): "Evaluating bed-material transport equations using field measurements in a sandy gravel-bed stream (Arbúcies, NE Spain)". Earth Surface Processes and Landforms, 22, 2, 121-130Batalla, R.J. Martín-Vide, J.P. (2001) "Thresholds of particle entrainment in a poorly sorted sandy gravel-bed river". Catena 44, 223-243Batalla, R.J., Sala, M., Werrity, A. (1995): "Sediment budget focused on solid material transport in a subhumid Mediterranean drainage basin". Zeitschrift für Geomorphologie, 29, 2, 249-264Church, M.A., McLean, D.G. & Wolcott, J.F. (1987): "River bed gravels: sampling and analysis". A: Thorne, C.R., Barthurst, J.C. & Hey, R.D. (eds.): Sediment transport in gravel-bed rivers. John Wiley & Sons, 43-88Garde, R.J., Ranga Raju, K.G (1977) "Mechanics of sediment transportation and alluvial stream problems". John Wiley and sons, New York 1977.Gutiérrez, C. (1999) "La Tordera. Perspectiva geograficohistòrica d'un riu". Publicacions de la rectoria vella. Sant Celoni.Leopold, L.B., Wolman, M.G., Miller, J.P. (1964) "Fluvial proceses in geomorphology". Dover Publications, New York.Martín Vide, J.P. (2002) "Ingeniería fluvial". Edicions UPC, Barcelona 1997 e "Ingeniería de ríos", Edicions UPC, Barcelona 2002.Pedraza, P. (1998) "Estudio de la erosión general en el río Tordera". Tesina de especialidad, Escuela T.S. de Ing. de Caminos, UPC.Rovira, A. (2001) "Balanç de sediment i dinàmica fluvial en un riu de règim hidrològic transitori (tram final de la Tordera)". Tesi Doctoral, Universitat de Barcelona.Sala, M. (1978) "La cuenca del Tordera. Estudio geomorfológico". Tesis doctoral. Universitat de Barcelona.Schreider, M., Scacchi, G., Franco, F., Fuentes, R., Moreno, Ch. (2001) "Aplicación del método de Lischtvan y Lebediev al cálculo de la erosión general". Ingeniería hidráulica en México, XVI,1, pp.15-25.Wolman, M.G. (1954) "A method of sampling coarse bed-material". American Geophys. Union Trans., 35, 951-956

Die Parteien entscheiden längst nicht mehr

Am 8. November wird in den USA nicht nur ein neuer Präsident, sondern auch ein neuer Kongress gewählt. Eine erneute Blockadehaltung könnte das Land zum Stillstand bringen und den sozialen Frieden gefährden

The state of art of the drought studies in Spain

Póster elaborado para el WCRP Workshop on Drought Predictability and Prediction in a Changing Climate celebrado en Barcelona del 2 al 4 de marzo de 201

Recent advances in the interrelationship of vegetation and climate in Spain

Póster elaborado para el WCRP Open Science Conference celebrado en Denver del 24 al 28 de octubre de 201