Person: Polo Sánchez, Irene
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First Name
Irene
Last Name
Polo Sánchez
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Físicas
Department
Física de la Tierra y Astrofísica
Area
Física de la Tierra
Identifiers
14 results
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Now showing 1 - 10 of 14
Item Can the boundary profiles at 26ºN be used to extract buoyancy-forced Atlantic Meridional Overturning Circulation signals?(Ocean science, 2020) Polo Sánchez, Irene; Haines, Keith; Robson, Jon; Thomas, ChristopherThe temporal variability of the Atlantic Meridional Overturning Circulation (AMOC) is driven both by direct wind stresses and by the buoyancy-driven formation of North Atlantic Deep Water over the Labrador Sea and Nordic Seas. In many models, low-frequency density variability down the western boundary of the Atlantic basin is linked to changes in the buoyancy forcing over the Atlantic subpolar gyre (SPG) region, and this is found to explain part of the geostrophic AMOC variability at 26◦ N. In this study, using different experiments with an ocean general circulation model (OGCM), we develop statistical methods to identify characteristic vertical density profiles at 26◦ N at the western and eastern boundaries, which relate to the buoyancy-forced AMOC. We show that density anomalies due to anomalous buoyancy forcing over the SPG propagate equatorward along the western Atlantic boundary (through 26◦ N), eastward along the Equator, and then poleward up the eastern Atlantic boundary. The timing of the density anomalies appearing at the western and eastern boundaries at 26◦ N reveals ∼ 2– 3-year lags between boundaries along deeper levels (2600– 3000 m). Record lengths of more than 26 years are required at the western boundary (WB) to allow the buoyancy-forced signals to appear as the dominant empirical orthogonal function (EOF) mode. Results suggest that the depth structure of the signals and the lagged covariances between the boundaries at 26◦ N may both provide useful information for detecting propagating signals of high-latitude origin in more complex models and potentially in the observational RAPID (Rapid Climate Change programme) array. However, time filtering may be needed, together with the continuation of the RAPID programme, in order to extend the time period.Item Relationships among Intermodel Spread and Biases in Tropical Atlantic Sea Surface Temperatures(Journal of Climate, 2019) Mohino Harris, Elsa; Rodríguez De Fonseca, María Belén; Mechoso, C. Roberto; Losada Doval, Teresa; Polo Sánchez, IreneState-of-the-art general circulation models show important systematic errors in their simulation of sea surface temperatures (SST), especially in the tropical Atlantic. In this work the spread in the simulation of climatological SST in the tropical Atlantic by 24 CMIP5 models is examined, and its relationship with the mean systematic biases in the region is explored. The modes of intermodel variability are estimated by applying principal component (PC) analysis to the SSTs in the region 70ºW–20ºE, 20ºS–20ºN. The intermodel variability is approximately explained by the first three modes. The first mode is related to warmer SSTs in the basin, shows worldwide connections with same-signed loads over most of the tropics, and is connected with lower low cloud cover over the eastern parts of the subtropical oceans. The second mode is restricted to the Atlantic, where it shows negative and positive loads to the north and south of the equator, respectively, and is connected to a too weak Atlantic meridional overturning circulation (AMOC). The third mode is related to the double intertropical convergence zone bias in the Pacific and to an interhemispheric asymmetry in the net radiation at the top of the atmosphere. The structure of the second mode is closer to the mean bias than that of the others in the tropical Atlantic, suggesting that model difficulties with the AMOC contribute to the regional biases. State-of-the-art general circulation models show important systematic errors in their simulation of sea surface tem- peratures (SST), especially in the tropical Atlantic. In this work the spread in the simulation of climatological SST in the tropical Atlantic by 24 CMIP5 models is examined, and its relationship with the mean systematic biases in the region is explored. The modes of intermodel variability are estimated by applying principal component (PC) analysis to the SSTs in the region 708W–208E, 208S–208N. The intermodel variability is approximately explained by the first three modes. The first mode is related to warmer SSTs in the basin, shows worldwide connections with same-signed loads over most of the tropics, and is connected with lower low cloud cover over the eastern parts of the subtropical oceans. The second mode is restricted to the Atlantic, where it shows negative and positive loads to the north and south of the equator, respectively, and is connected to a too weak Atlantic meridional overturning circulation (AMOC). The third mode is related to the double intertropical convergence zone bias in the Pacific and to an interhemispheric asymmetry in the net radiation at the top of the atmosphere. The structure of the second mode is closer to the mean bias than that of the others in the tropical Atlantic, suggesting that model difficulties with the AMOC contribute to the regional biases.- Project number: 311
Item Metodologías participativas e innovadoras en la docencia universitaria desde un enfoque de género(2020) Martínez Martín, Irene; Rabazas Romero, Teresa; Sanz Simón, Carlos; Resa Ocio, Ainhoa; Ramos Zamora, Sara; Guillen Gomez de Marcos, Eva; Sonlleva Velasco, Miriam; Sánchez Serrano, Jose Manuel; Santiesteban, Andra; Crespo Puras, María del Carmen; Polo Sánchez, Irene; Canales Serrano, Antonio Francisco; Bustelo Ruesta, María Dolores; San Landaluze, Jon; Zubillaga del Rio, AinaraAnálisis y diseño de metodologías docentes innovadoras para mejorar la participación desde un enfoque de género. Incorporación de autorreflexiones en torno a las dimensiones de la participación y su componente de género, buscando la transformación. Item Variabilidad del Atlántico tropical: interacciones océano-atmósfera e impactos en el clima(2008) Polo Sánchez, Irene; Rodríguez de Fonseca, María Belén; Lazar, AlbanEste trabajo profundiza en la Variabilidad del Atlántico Tropical (VAT) centrándose en el papel de las interacciones océano-atmósfera: 1) caracteriza los patrones con bondad predictiva de la Temperatura Superficial del Mar (TSM) del Atlántico Tropical (AT) que covarían con la lluvia estival en el noroeste de África e invernal en Europa. 2) explica las interacciones océano-atmósfera implicadas en la evolución de estos modos y evalua el ajuste oceánico a través de ondas oceánicas. El patrón principal de TSM que covaría con la precipitación invernal en Europa tiene su centro sobre el Atlántico Norte Subtropical (ANS) y posee bondad predictiva en la Península Ibérica y el Norte de África. La TSM sobre el ANS está controlada por los flujos de calor superficiales turbulentos y por los procesos de afloramiento del sistema Mauritania/Senegal. El patrón principal de TSM que covaría con la lluvia estival en el noroeste de África relaciona el Modo Ecuatorial (ME) con la lluvia sobre la costa del Golfo de Guinea. El ME tiene su origen sobre el sistema de afloramiento de Angola/Benguela, evoluciona a través de ondas de Rossby oceánicas y se amortigua por flujos de calor latente y por una onda de Kelvin ecuatorial. El ME podría estar liderando una Niña pacífica seis meses antes. Existe actividad de ondas oceánicas de Kelvin sobre el AT con un periodo predominante de 50 días. Estas ondas viajan desde el oeste ecuatorial propagándose hacia el este atrapadas en el ecuador hasta la costa africana, desde donde se propagan hacia los polos atrapadas en la costa hasta alcanzar los 12º de latitud. Se propone un mecanismo de generación de ondas de Kelvin que implica anomalías del bombeo de Ekman inducidas por cambios en la posición de la Zona de Convergencia Inter-Tropical. Este trabajo pone de manifiesto la importancia de los sistemas de afloramiento costero y la actividad de las ondas oceánicas en la VAT. [ABSTRACT]This study deals with the Tropical Atlantic Variability (TAV), in particular with the role of the ocean-atmosphere interactions: 1) characterizes the Sea Surface Temperature (SST) patterns over the Tropical Atlantic (TA) with a preciting value, which covary with the summer West African rainfall and the winter European precipitation. 2) explains the ocean-atmosphere interactions which are implied in the time-evolution of the modes and evalues the oceanic adjustment throughout oceanic waves. The leading SST pattern which covaries with the winter European precipitation has a center of action over the Subtropical Northe Atlantic (SNA) and has a predictive skill for the precipitation over Iberian Peninsula and North of Africa. The SST over SNA is led by the surface turbulent heat fluxes and by the upwelling processes over the Mauritanian/Senegal system. The leading SST pattern, which covaries with the summer rainfall over West Africa, relates the Equatorial Mode (EM) to the rainfalll over the Gulf of Guinea. The EM has its origin over the Angola/Benguela upwelling system and evolves through oceanic Rossby waves and is damped by latent heat fluxes and a oceanic equatorial Kelvin wave. The EM could be leading a Pacific La Niña six months in advance. There is Kelvin wave activity over the TA with a predominant period of 50 days. These waves travel eastward equatorially trapped from the western equator up to the african coast, from where they propagate poleward coastally trapped as far as 12º latitude. A mechanism is proposed to explain the Kelvin waves generation that implies Ekman pumping InterTropical Convergence Zone shift-induced anomalies. This work highlights the importance of the African coastal upwelling systems and the oceanic waves activity in the TAV.- Project number: PIMCD244/23-24
Item Cambiando el rol del profesorado en el aula de transmisor a facilitador(2024) De La Cámara Illescas, Álvaro; Calvo Fernández, Natalia; Ábalos Álvarez, Marta; Durán Montejano, Luis; García Herrera, Ricardo Francisco; González Rouco, Jesús Fidel; Losada Doval, Teresa; Montoya Redondo, María Luisa; Negredo Moreno, Ana María; Pavón Carrasco, Francisco Javier; Polo Sánchez, Irene; Rodríguez De Fonseca, María Belén; Sastre Marugán, Mariano; Yagüe Anguis, Carlos; Zurita Gotor, Pablo; De La Cámara Illescas, ÁlvaroEste proyecto propone un cambio del rol del docente en el aula de transmisor a facilitador. Para ello, se apuesta por implantar metodologías que favorezcan el aprendizaje cooperativo en el aula y potencien el desarrollo de competencias transversales. - Project number: 151
Item Meteolab como herramienta educativa de Meteorología en el Aula(2021) Rodríguez De Fonseca, María Belén; Ábalos Álvarez, Marta; Alvarez Solas, Jorge; Ayarzagüena Porras, Blanca; Benito Barca, Samuel; Calvo Fernández, Natalia; de la Cámara Illescas, Alvaro; Durán Montejano, Luis; García Herrena, Ricardo; Garrido Pérez, José Manuel; Gómara Cardalliaguet, Iñigo; Losada Doval, Teresa; Mohino Harris, Elsa; Montoya Redondo, Marisa Luisa; Ordoñez García, Carlos; Polo Sánchez, Irene; Robinson, Alexander James; Sastre Marugán, Mariano; Serrano Mendoza, Encarnación; Yagüe Anguis, Carlos; Zurita Gotor, Pablo; García Burgos, Marina; González Alemán, Juan Jesús; González Barras, Rosa María; González Rouco, Jesús Fidel; Martín Gómez, Verónica; Maqueda Burgos, GregorioEl Presente proyecto es una continuación de proyectos anteriores dentro de la plataforma de divulgación Meteolab. Meteolab es un proyecto de divulgación de Meteorología y Clima que tiene su origen en 2002, cuando se comenzaron a diseñar experimentos de bajo coste con materiales caseros para la Semana de la Ciencia de la Comunidad de Madrid (CAM). Con los años, se generó un conocimiento que se materializó en 2010 con la concesión de un Proyecto de Innovación Educativa (PIE) financiado por la Universidad Complutense de Madrid (UCM), dirigido por Belén Rodríguez de Fonseca. Gracias a este primer proyecto en el que trabajaron muchos profesores y alumnos de ciencias de la atmósfera, se gestó un portal web (meteolab.fis.ucm.es) en el que los experimentos se explicaban y se grababan para impulsar su difusión. Más adelante, en un segundo proyecto de Innovación Educativa, dirigido por la profesora Maria Luisa Montoya, los contenidos fueron traducidos al inglés. En concreto, los experimentos que componen Meteolab tienen como principal objetivo entender los principios y variables que determinan el comportamiento de las masas de aire en la atmósfera y de agua en el océano. La idea consiste en visualizar con experimentos sencillos las leyes físicas que gobiernan la atmósfera y el océano: movimientos horizontales y verticales, cambios de estado, mezcla y equilibrio, así como la interacción entre componentes. Se persigue observar los procesos meteorológicos familiares, como son la formación de una nube, los tornados, la convección, la formación de borrascas o la lluvia, entendiendo los procesos físicos que los producen. Finalmente, Meteolab permite también visualizar fenómenos climáticos como el efecto invernadero, el fenómeno de El Niño, el deshielo del Ártico, la influencia de los volcanes en el clima o la subida del nivel del mar. Existe un catálogo de experimentos, la mayoría de los cuales pueden consultarse a través del portal meteolab.fis.ucm.es, encontrándose todos ellos físicamente localizados en el Laboratorio Elvira Zurita de la Facultad de Ciencias Físicas. Tras la experiencia acumulada durante los 18 años de existencia de Meteolab, en los que se han adecuado las explicaciones de los experimentos a distintos niveles de dificultad (infantil, primaria, secundaria, bachillerato y Universidad de mayores), se ha sugerido la idoneidad de adaptar los contenidos a los estudiantes del Grado en Física y del Máster en Meteorología y Geofísica de la UCM. Así, por ejemplo, cuando se explica la formación de una nube, se puede ir complicando el discurso dependiendo de los diferentes ciclos de la enseñanza. De esta manera, para un nivel de escuela primaria uno sólo tiene que explicar que el aire se enfría al ascender, y al enfriarse se forman gotas de agua que forman las nubes. Al llegar a secundaria, los estudiantes aprenden el concepto de presión atmosférica y la relación entre la temperatura, la presión y el volumen de una parcela de aire. Más adelante, en el Grado en Física, se estudia la tensión de vapor, la expansión adiabática y la existencia de núcleos de condensación. Finalmente, en el Máster en Meteorología se aprenden los distintos procesos de nucleación y tipos de nubes. Todos estos conceptos van complicando la explicación, por lo que un mismo experimento puede explicarse tanto en una escuela infantil como en una Universidad. Es por ello, que, aprovechando la plataforma de divulgación Meteolab, hemos decidido dar un paso adelante y adaptar y ampliar los contenidos de Meteolab, para así poder integrarlos en los currícula del Grado en Física y del Máster en Meteorología y Geofísica de la UCM. Con todo ello, los objetivos del presente proyecto han sido: -Implementar los experimentos de Meteolab en el Aula, tanto en las asignaturas de Grado como en las de Máster. -Adaptar los contenidos existentes del portal web Meteolab (meteolab.fis.ucm.es) a las asignaturas relacionadas con Meteorología del Grado en Física y del Máster en Meteorología y Geofísica, con el fin de visualizar procesos físicos que se explican en el aula. -Añadir a Meteolab nuevos contenidos en relación con la dinámica de la atmósfera y el cambio climático. -Evaluar la mejora de la comprensión por parte del alumnado de los procesos que tienen lugar principalmente en la atmósfera y el océano, y su relación con el clima y su variabilidad. Item Multidecadal variability of ENSO in a recharge oscillator framework(Environmental research letters, 2022) Crespo, Lander R.; Rodríguez De Fonseca, María Belén; Polo Sánchez, Irene; Keenlyside, Noel; Dommenget, DietmarWe use a conceptual recharge oscillator model to identify changes in El Niño and the Southern Oscillation (ENSO) statistics and dynamics during the observational record. The variability of ENSO has increased during the 20th century. The cross-correlation between sea surface temperature (SST) and warm water volume (WWV) has also changed during the observational record. From the 1970s onwards, the SST drives WWV anomalies with a lead-time of ten months and the WWV feedbacks onto the SST with a lead-time of eight months. This is reminiscent of a recharge-discharge mechanism of the upper ocean heat content. The full recharge-discharge mechanism is only observed from the 1970s onwards. This could be the result of the degradation of the quality of observations in the early part of the 20th century. However, it may also be a consequence of decadal changes in the coupling between WWV and SST. Additional analysis fitting the recharge oscillator model to the coupled state-of-the-art climate models indicates that ENSO properties show little decadal changes in the climate models. The disagreement in changes in ENSO properties between the reanalysis and the climate models can be due to errors in the available observational data or due to the models missing the low frequency variability and decadal wind trends. Longer and more reliable observational records would be required to validate our results.Item Impact of equatorial Atlantic variability on ENSO predictive skill(Nature communications, 2021) Exarchou, Eleftheria; Ortega, Pablo; Rodríguez De Fonseca, María Belén; Losada Doval, Teresa; Polo Sánchez, Irene; Prodhomme, CloéEl Niño-Southern Oscillation (ENSO) is a key mode of climate variability with worldwide climate impacts. Recent studies have highlighted the impact of other tropical oceans on its variability. In particular, observations have demonstrated that summer Atlantic Niños (Niñas) favor the development of Pacific Niñas (Niños) the following winter, but it is unclear how well climate models capture this teleconnection and its role in defining the seasonal predictive skill of ENSO. Here we use an ensemble of seasonal forecast systems to demonstrate that a better representation of equatorial Atlantic variability in summer and its lagged teleconnection mechanism with the Pacific relates to enhanced predictive capacity of autumn/winter ENSO. An additional sensitivity study further shows that correcting SST variability in equatorial Atlantic improves different aspects of forecast skill in the Tropical Pacific, boosting ENSO skill. This study thus emphasizes that new efforts to improve the representation of equatorial Atlantic variability, a region with long standing systematic model biases, can foster predictive skill in the region, the Tropical Pacific and beyond, through the global impacts of ENSO.Item ENSO coupling to the equatorial Atlantic: analysis with an extended improved recharge oscillator model(Frontiers in Marine Science, 2023) Crespo Miguel, Rodrigo; Polo Sánchez, Irene; Mechoso, Carlos R.; Rodríguez De Fonseca, María Belén; Cao García, Francisco JavierIntroduction: Observational and modeling studies have examined the interactions between El Niño-Southern Oscillation (ENSO) and the equatorial Atlantic variability as incorporated into the classical charge-recharge oscillator model of ENSO. These studies included the role of the Atlantic in the predictability of ENSO but assumed stationarity in the relationships, i.e., that models’ coefficients do not change overtime. Arecentworkbytheauthors has challenged the stationarity assumption in the ENSO framework but without considering the equatorial Atlantic influence on ENSO. Methods: The present paper addresses the changing relationship between ENSO and the Atlantic El Niño using an extended version of the recharge oscillator model. The classical two-variable model of ENSO is extended by adding a linear coupling on the SST anomalies in the equatorial Atlantic. The model’s coefficients are computed for different periods. This calculation is done using two methods tofitthemodel tothe data: (1) the traditional method (ReOsc), and (2) a novel method (ReOsc+) based on fitting the Fisher’s Z transform of the auto and cross-correlation functions. Results: Weshowthat, duringthe 20th century, the characteristic dampingrate of the SST and thermocline depth anomalies in the Pacific have decreased in time by a factor of 2 and 3, respectively. Moreover, the damping time of the ENSO fluctuations has doubled from 10 to 20 months, and the oscillation period of ENSO has decreased from 60-70 months before the 1960s to 50 months afterward. These two changes have contributed to enhancing ENSO amplitude. The results also show that correlations between ENSO and the Atlantic SST strengthened after the 70s and the way in which the impact of the equatorial Atlantic is added to the internal ENSO variability. Conclusions: The remote effects of the equatorial Atlantic on ENSO must be considered in studies of ENSO dynamics and predictability during specific time-periods. Our results provide further insight into the evolution of the ENSO dynamics anditscoupling to the equatorial Atlantic, as well as an improved tool to study the coupling of climatic and ecological variables.Item Ocean dynamics shapes the structure and timing of Atlantic Equatorial Modes(Journal of geophysical research-oceans, 2019) Martín Rey, Marta; Polo Sánchez, Irene; Rodríguez De Fonseca, María Belén; Lazar, Alban; Losada Doval, TeresaA recent study has brought to light the co‐existence of two distinct Atlantic Equatorial Modes during negative phases of the Atlantic Multidecadal Variability: the Atlantic Niño and Horse‐Shoe (HS) mode. Nevertheless, the associated air‐sea interactions for HS mode have not been explored so far and the prevailing dynamic view of the Atlantic Niño has been questioned. Here, using a forced ocean model simulation, we find that for both modes, ocean dynamics is essential to explain the equatorial SST variations, while air‐sea fluxes control the off‐equatorial SST anomalies. Moreover, we demonstrate the key role played by ocean waves in shaping their distinct structure and timing. For the positive phase of both Atlantic Niño and HS, anomalous westerly winds trigger a set of equatorial downwelling Kelvin waves (KW) during spring‐summer. These dKWs deepen the thermocline, favouring the equatorial warming through vertical diffusion and horizontal advection. Remarkably, for the HS, an anomalous north‐equatorial wind stress curl excites an upwelling Rossby wave (RW), which propagates westward and is reflected at the western boundary becoming an equatorial upwelling KW. The uKW propagates to the east, activating the thermocline feedbacks responsible to cool the sea surface during summer months. This RW‐reflected mechanism acts as a negative feedback causing the early termination of the HS mode. Our results provide an improvement in the understanding of the TAV modes and emphasize the importance of ocean wave activity to modulate the equatorial SST variability. These findings could be very useful to improve the prediction of the Equatorial Modes.