Persona: Yela González, Margarita
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Instituto Nacional de Técnica Aeroespacial
El Instituto Nacional de Técnica Aeroespacial es el Organismo Público de Investigación (OPI) dependiente del Ministerio de Defensa. Además de realizar actividades de investigación científica y de desarrollo de sistemas y prototipos en su ámbito de conocimiento, presta servicios tecnológicos a empresas, universidades e instituciones.
El INTA está especializado en la investigación y el desarrollo tecnológico, de carácter dual, en los ámbitos de la Aeronáutica, Espacio, Hidrodinámica, Seguridad y Defensa.
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Yela González
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Publicación Acceso Abierto Using the Perseverance MEDA-RDS to identify and track dust devils and dust-lifting gust fronts(Frontiers, 2023-10-11) Toledo, D.; Apéstigue, Víctor; Martínez Oter, J.; Franchi, Fulvio; Serrano, F.; Yela González, Margarita; De la Torre Juárez, M.; Rodríguez Manfredi, J. A.; Arruego, Ignacio; European Commission (EC); Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO)In the framework of the Europlanet 2024 Research Infrastructure Transnational Access programme, a terrestrial field campaign was conducted from 29 September to 6 October 2021 in Makgadikgadi Salt Pans (Botswana). The main goal of the campaign was to study in situ the impact of the dust devils (DDs) on the observations made by the radiometer Radiation and Dust Sensor (RDS), which is part of the Mars Environmental Dynamics Analyzer instrument, on board NASA’s Mars 2020 Perseverance rover. Several DDs and dust lifting events caused by non-vortex wind gusts were detected using the RDS, and the different impacts of these events were analyzed in the observations. DD diameter, advection velocity, and trajectory were derived from the RDS observations, and then, panoramic videos of such events were used to validate these results. The instrument signal variations produced by dust lifting (by vortices or wind gusts) in Makgadikgadi Pans are similar to those observed on Mars with the RDS, showing the potential of this location as a Martian DD analog.Publicación Acceso Abierto Polar Stratospheric Clouds Detection at Belgrano II Antarctic Station with Visible Ground-Based Spectroscopic Measurements(Multidisciplinary Digital Publishing Institute (MDPI), 2021-04-07) Gómez Martín, L.; Toledo, D.; Prados Roman, C.; Jose, Adame; Ochoa, H.; Yela González, Margarita; Agencia Estatal de Investigación (AEI); Gómez Martín, L. [0000-0002-6655-7659]; Prados Roman, C. [0000-0001-8332-0226]; Adame, J. A. [0000-0002-6302-7193]By studying the evolution of the color index (CI) during twilight at high latitudes, polar stratospheric clouds (PSCs) can be detected and characterized. In this work, this method has been applied to the measurements obtained by a visible ground-based spectrometer and PSCs have been studied over the Belgrano II Antarctic station for years 2018 and 2019. The methodology applied has been validated by full spherical radiative transfer simulations, which confirm that PSCs can be detected and their altitude estimated with this instrumentation. Moreover, our investigation shows that this method is useful even in presence of optically thin tropospheric clouds or aerosols. PSCs observed in this work have been classified by altitude. Our results are in good agreement with the stratospheric temperature evolution obtained by the global meteorological model ECMWF (European Centre for Medium Range Weather Forecasts) and with satellite PSCs observations from CALIPSO (Cloud-Aerosol-Lidar and Infrared Pathfinder Satellite Observations). To investigate the presence and long-term evolution of PSCs, the methodology used in this work could also be applied to foreseen and/or historical observations obtained with ground-based spectrometers such e. g. those dedicated to Differential Optical Absorption Spectroscopy (DOAS) for trace gas observation in Arctic and Antarctic sites.Publicación Acceso Abierto Intercomparison of MAX-DOAS vertical profile retrieval algorithms: studies on field data from the CINDI-2 campaign(European Geoscience Union (EGU), 2021-01-04) Tirpitz, J. L.; Frieb, U.; Hendrick, F.; Alberti, C.; Allaart, Marc; Apituley, A.; Bais, A.; Beirle, S.; Berkhout, S.; Bognar, K.; Bösch, T.; Bruchkouski, I.; Cede, A.; Lok Chan, K.; Den Hoed, M.; Donner, S.; Drosoglou, T.; Fayt, C.; Friedrich, M. M.; Frumau, A.; Gast, L.; Gielen, C.; Gómez Martín, L.; Hao, N.; Hensen, A.; Henzing, B.; Hermans, C.; Jin, J.; Kreher, K.; Kuhn, J.; Lampel, J.; Li, A.; Liu, C.; Liu, H.; Ma, J.; Merlaud, A.; Peters, E.; Pinardi, G.; Piters, Ankie.; Platt, U.; Puentedura, O.; Richter, A.; Schmitt, S.; Spinei, E.; Stein Zweers, D.; Strong, K.; Swart, D.; Tack, F.; Tiefengraber, M.; Van der Hoff, R.; Van Roozendael, M.; Vlemmix, T.; Vonk, J.; Wagner, T.; Wang, Y.; Wang, Z.; Wenig, M.; Wiegner, M.; Wittrock, F.; Xie, P.; Xing, C.; Xu, J.; Yela González, Margarita; Zhang, C.; Zhao, X.; European Space Agency (ESA); European Commission (EC); Canadian Space Agency; National Natural Science Foundation of China (NSFC); Natural Sciences and Engineering Research Council of Canada; Deutsche Forschungsgemeinschaft (DFG); European Research Council (ERC); Ministerio de Economía y Competitividad (MINECO); Frieß, U. [0000-0001-7176-7936]; Alberti, C. [0000-0002-1574-5393]; Apituley, A. [0000-0001-8821-6348]; Bais, A. [0000-0003-3899-2001]; Beirle, S. [0000-0002-7196-0901]; Berkhout, S. [0000-0001-5447-8868]; Bognar, K. [0000-0003-4619-2020]; Bösch, T. [0000-0003-4230-8129]; Donner, S. [0000-0001-8868-167X]; Frumau, A. [0000-0001-5940-0285]; Gómez Martín, L. [0000-0002-6655-7659]; Henzing, B. [0000-0001-6456-8189]; Lampel, J. [0000-0001-7370-9342]; Liu, C. [0000-0002-3759-9219]; Ma, J. [0000-0002-9510-5432]; Peters, E. [0000-0002-8380-3137]; Pinardi, G. [0000-0001-5428-916X]; Puentedura, O. [0000-0002-4286-1867]; Richter, A. [0000-0003-3339-212X]; Stein Zweers, D. [0000-0002-1180-5790]; Strong, K. [0000-0001-9947-1053]; Swart, D. [0000-0002-6128-337X]; Vlemmix, T. [0000-0003-2584-3402]; Wang, Y. [0000-0002-9828-9871]; Zhang, C. [0000-0003-2092-9135]The second Cabauw Intercomparison of Nitrogen Dioxide measuring Instruments (CINDI-2) took place in Cabauw (the Netherlands) in September 2016 with the aim of assessing the consistency of multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements of tropospheric species (NO2, HCHO, O3, HONO, CHOCHO and O4). This was achieved through the coordinated operation of 36 spectrometers operated by 24 groups from all over the world, together with a wide range of supporting reference observations (in situ analysers, balloon sondes, lidars, long-path DOAS, direct-sun DOAS, Sun photometer and meteorological instruments). In the presented study, the retrieved CINDI-2 MAX-DOAS trace gas (NO2, HCHO) and aerosol vertical profiles of 15 participating groups using different inversion algorithms are compared and validated against the colocated supporting observations, with the focus on aerosol optical thicknesses (AOTs), trace gas vertical column densities (VCDs) and trace gas surface concentrations. The algorithms are based on three different techniques: six use the optimal estimation method, two use a parameterized approach and one algorithm relies on simplified radiative transport assumptions and analytical calculations. To assess the agreement among the inversion algorithms independent of inconsistencies in the trace gas slant column density acquisition, participants applied their inversion to a common set of slant columns. Further, important settings like the retrieval grid, profiles of O3, temperature and pressure as well as aerosol optical properties and a priori assumptions (for optimal estimation algorithms) have been prescribed to reduce possible sources of discrepancies. The profiling results were found to be in good qualitative agreement: most participants obtained the same features in the retrieved vertical trace gas and aerosol distributions; however, these are sometimes at different altitudes and of different magnitudes. Under clear-sky conditions, the root-mean-square differences (RMSDs) among the results of individual participants are in the range of 0.01–0.1 for AOTs, (1.5–15) ×1014molec.cm−2 for trace gas (NO2, HCHO) VCDs and (0.3–8)×1010molec.cm−3 for trace gas surface concentrations. These values compare to approximate average optical thicknesses of 0.3, trace gas vertical columns of 90×1014molec.cm−2 and trace gas surface concentrations of 11×1010molec.cm−3 observed over the campaign period. The discrepancies originate from differences in the applied techniques, the exact implementation of the algorithms and the user-defined settings that were not prescribed. For the comparison against supporting observations, the RMSDs increase to a range of 0.02–0.2 against AOTs from the Sun photometer, (11–55)×1014molec.cm−2 against trace gas VCDs from direct-sun DOAS observations and (0.8–9)×1010molec.cm−3 against surface concentrations from the long-path DOAS instrument. This increase in RMSDs is most likely caused by uncertainties in the supporting data, spatiotemporal mismatch among the observations and simplified assumptions particularly on aerosol optical properties made for the MAX-DOAS retrieval. As a side investigation, the comparison was repeated with the participants retrieving profiles from their own differential slant column densities (dSCDs) acquired during the campaign. In this case, the consistency among the participants degrades by about 30 % for AOTs, by 180 % (40 %) for HCHO (NO2) VCDs and by 90 % (20 %) for HCHO (NO2) surface concentrations. In former publications and also during this comparison study, it was found that MAX-DOAS vertically integrated aerosol extinction coefficient profiles systematically underestimate the AOT observed by the Sun photometer. For the first time, it is quantitatively shown that for optimal estimation algorithms this can be largely explained and compensated by considering biases arising from the reduced sensitivity of MAX-DOAS observations to higher altitudes and associated a priori assumptions.Publicación Acceso Abierto The September 2002 Antarctic vortex major warming as observed by visible spectroscopy and ozone soundings(Taylor & Francis Ltd, 2005-08) Yela González, Margarita; Parrondo, María Concepción; Gil Moulet, Manuel; Rodríguez, S.; Araujo, J.; Ochoa, H.; Deferrari, Guillermo Alejandro; Diaz, Susana BeatrizThe record of O3 total column and NO2 obtained by visible spectroscopy at Ushuaia (55° S), Marambio (64° S) and Belgrano (78° S) and vertical ozone profiles from the latter station provide insight into the unprecedented major warming observed above Antarctica in the last week of September 2002. From 18 September to 25 September the temperature increased 54°C at the isentropic level of 700 K. The temperature anomaly was observed down to the level of 300 K in which a well-defined tropopause was established. From comparison of the ozone profiles before and during the event, it can be seen that a fast increase in O3 took place basically above 500 K, but the layer where the ozone hole occurs was barely affected. Low potential vorticity values above Belgrano occurred only at levels above 500 K, confirming that the vortex split was confined to heights above the layer of the Antarctic spring depletion. The signature of poleward-transported air is clearly visible from the NO2 column departure from the envelope of the previous years in all three stations. NO2 columns larger than typical for ozone hole conditions by 400% were observed at Belgrano. Diurnal variations provide evidence of non-denitrified extra-vortex air.Publicación Acceso Abierto Mid-winter lower stratosphere temperatures in the Antarctic vortex: comparison between observations and ECMWF and NCEP operational models(EGU European Geosciences Union, 2007-01-24) Parrondo, María Concepción; Yela González, Margarita; Gil, M.; Von der Gathen, P.; Ochoa, H.Radiosonde temperature profiles from Belgrano (78° S) and other Antarctic stations have been compared with European Centre for Medium-Range Weather Forecasting (ECMWF) and National Centers for Environmental Prediction (NCEP) operational analyses during the winter of 2003. Results show good agreement between radiosondes and NCEP and a bias in the ECMWF model which is height and temperature dependent, being up to 3°C too cold at 80 and 25–30 hPa, and hence resulting in an overestimation of the predicted potential PSC areas. Here we show the results of the comparison and discuss the potential implications that this bias might have on the ozone depletion computed by Chemical Transport Models based on ECMWF temperature fields, after rejecting the possibility of a bias in the sondes at extreme low temperatures.Publicación Acceso Abierto Drying of the Martian mesosphere during aphelion induced by lower temperatures(Springer Nature, 2024-11-20) Toledo, D.; Rannou, P.; Apéstigue, Víctor; Rodríguez Veloso, Raúl; Rodríguez Manfredi, J. A.; Arruego, Ignacio; Martínez, Germán M.; Tamppari, L. K.; Munguira, A.; Lorenz, Ralph; Stcherbinine, Aurélien; Montmessin, F.; Sánchez Lavega, Agustín; Patel, P.; Smith, Michael D.; Lemmon, M. T.; Vicente Retortillo, Álvaro; Newman, C. E.; Viúdez Moreiras, Daniel; Hueso, R.; Bertrand, T.; Pla García, J.; Yela González, Margarita; De la Torre Juárez, M.; Ministerio de Ciencia e Innovación (MICINN); Jet Propulsion Laboratory (JPL); National Aeronautics and Space Administration (NASA); Gobierno Vasco; Agencia Estatal de Investigación (AEI); Unidad de Excelencia Científica María de Maeztu Instituto de Astrofísica de Cantabria, MDM-2017-0765The formation of water ice clouds or hazes on Mars imposes substantial limitations on the vertical transport of water into the middle-upper atmosphere, impacting the planet’s hydrogen loss. Recent observations made by the Mars Environmental Dynamics Analyzer instrument onboard Mars 2020 Perseverance rover have shown a marked decline in water ice abundance within the mesosphere (above 35-40 km) when Mars is near its aphelion (near the northern summer solstice), notably occurring during solar longitudes (Ls) between Ls 70∘ and 80∘. Orbital observations around the same latitudes indicate that temperatures between ~ 30-40 km reach a minimum during the same period. Using cloud microphysics simulations, we demonstrate that this decrease in temperature effectively increases the amount of water cold-trapped at those altitudes, confining water ice condensation to lower altitudes. Similarly, the reinforcement of the cold trap induced by the lower temperatures results in significant reductions in the water vapor mixing ratio above 35–40 km, explaining the confinement of water vapor observed around aphelion from orbiters.Publicación Acceso Abierto Ground-based validation of the Copernicus Sentinel-5P TROPOMI NO2 measurements with the NDACC ZSL-DOAS, MAX-DOAS and Pandonia global networks(European Geoscience Union (EGU), 2021-01-22) Verhoelst, T.; Compernolle, S.; Pinardi, G.; Lambert, J. C.; Eskes, H. J.; Eichmann, K. U.; Fjaeraa, A. M.; Granville, J.; Niemeijer, S.; Cede, A.; Tiefengraber, M.; Hendrick, F.; Pazmiño, A.; Bais, A.; Bazureau, A.; Folkert Boersma, K.; Bognar, K.; Dehn, A.; Donner, S.; Elokhov, A.; Gebetsberger, M.; Goutail, F.; Grutter de la Mora, M.; Gruzdev, A.; Gratsea, M.; Hansen, G. H.; Irie, H.; Jepsen, N.; Kanaya, Y.; Karagkiozidis, D.; Kivi, R.; Kreher, K.; Levelt, P. F.; Liu, C.; Müller, M.; Navarro-Comas, Mónica; Piters, Ankie; Pommereau, J. P.; Portafaix, T.; Prados Roman, C.; Puentedura, O.; Querel, R.; Remmers, J.; Richter, A.; Rimmer, J.; Rivera Cárdenas, C.; Saavedra de Miguel, Lidia; Sinyakov, V. P.; Stremme, W.; Strong, K.; Van Roozendael, M.; Pepijn Veefkind, J.; Wagner, T.; Wittrock, F.; Yela González, Margarita; Zehner, C.; European Space Agency (ESA); French Institut National des Sciences de l'Univers (INSU); Centre National D'Etudes Spatiales (CNES); Centre National de la Recherche Scientifique (CNRS); Institut polaire français Paul Emile Victor (IPEV); Belgian Science Policy Office (BELSPO); Verhoelst, T. [0000-0003-0163-9984]; Compernolle, S. [0000-0003-0872-0961]; Pinardi, G. [0000-0001-5428-916X]; Eskes, H. [0000-0002-8743-4455]; Bais, A. [0000-0003-3899-2001]; Folkert Boersma, K. [0000-0002-4591-7635]; Bognar, K. [0000-0003-4619-2020]; Donner, S. [0000-0001-8868-167X]; Elokhov, A. [0000-0003-4725-9186]; Grutter de la Mora, M. [0000-0001-9800-5878]; Gruzdev, A. [0000-0003-3224-1012]; Karagkiozidis, D. [0000-0002-3595-0538]; Kivi, R. [0000-0001-8828-2759]; Liu, C. [0000-0002-3759-9219]; Müller, M. [0000-0001-5284-5425]; Pommereau, J. P. [0000-0002-8285-9526]; Prados Roman, C. [0000-0001-8332-0226]; Puentedura, O. [0000-0002-4286-1867]; Querel, R. [0000-0001-8792-2486]; Richter, A. [0000-0003-3339-212X]; Rivera Cárdenas, C. [0000-0002-8617-265X]; Stremme, W. [0000-0003-0791-3833]; Strong, K. [0000-0001-9947-1053]; Pepijn Veefkind, J. [0000-0003-0336-6406]This paper reports on consolidated ground-based validation results of the atmospheric NO2 data produced operationally since April 2018 by the TROPOspheric Monitoring Instrument (TROPOMI) on board of the ESA/EU Copernicus Sentinel-5 Precursor (S5P) satellite. Tropospheric, stratospheric, and total NO2 column data from S5P are compared to correlative measurements collected from, respectively, 19 Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS), 26 Network for the Detection of Atmospheric Composition Change (NDACC) Zenith-Scattered-Light DOAS (ZSL-DOAS), and 25 Pandonia Global Network (PGN)/Pandora instruments distributed globally. The validation methodology gives special care to minimizing mismatch errors due to imperfect spatio-temporal co-location of the satellite and correlative data, e.g. by using tailored observation operators to account for differences in smoothing and in sampling of atmospheric structures and variability and photochemical modelling to reduce diurnal cycle effects. Compared to the ground-based measurements, S5P data show, on average, (i) a negative bias for the tropospheric column data, of typically −23 % to −37 % in clean to slightly polluted conditions but reaching values as high as −51 % over highly polluted areas; (ii) a slight negative median difference for the stratospheric column data, of about −0.2 Pmolec cm−2, i.e. approx. −2 % in summer to −15 % in winter; and (iii) a bias ranging from zero to −50 % for the total column data, found to depend on the amplitude of the total NO2 column, with small to slightly positive bias values for columns below 6 Pmolec cm−2 and negative values above. The dispersion between S5P and correlative measurements contains mostly random components, which remain within mission requirements for the stratospheric column data (0.5 Pmolec cm−2) but exceed those for the tropospheric column data (0.7 Pmolec cm−2). While a part of the biases and dispersion may be due to representativeness differences such as different area averaging and measurement times, it is known that errors in the S5P tropospheric columns exist due to shortcomings in the (horizontally coarse) a priori profile representation in the TM5-MP chemical transport model used in the S5P retrieval and, to a lesser extent, to the treatment of cloud effects and aerosols. Although considerable differences (up to 2 Pmolec cm−2 and more) are observed at single ground-pixel level, the near-real-time (NRTI) and offline (OFFL) versions of the S5P NO2 operational data processor provide similar NO2 column values and validation results when globally averaged, with the NRTI values being on average 0.79 % larger than the OFFL values.Publicación Restringido Measurement of dust optical depth using the solar irradiance sensor (SIS) onboard the ExoMars 2016 EDM(Elsevier, 2017-01-20) Toledo, D.; Arruego, Ignacio; Apéstigue, Víctor; Jiménez Martín, Juan José; Gómez Martín, L.; Yela González, Margarita; Rannou, P.; Pommereau, J. P.; Instituto Nacional de Técnica Aeroespacial (INTA); Ministerio de Economía y Competitividad (MINECO)"The solar irradiance sensor (SIS) was included in the DREAMS package onboard the ExoMars 2016 Entry Descent and Landing Demonstrator Module, and has been selected in the METED meteorological station onboard the ExoMars 2020 Lander. This instrument is designed to measure at different time intervals the scattered flux or the sum of direct flux and scattered flux in UVA (315-400 nm) and NIR (700-1100 nm) bands. For SIS'16, these measurements are performed by a total of 3 sensors per band placed at the faces of a truncated tetrahedron with face inclination angles of 60. The principal goal of SIS'16 design is to perform measurements of the dust opacity in UVA and NIR wavelengths ranges, crucial parameters in the understanding of the Martian dust cycle. The retrieval procedure is based on the use of radiative transfer simulations to reproduce SIS observations acquired during daytime as a function of dust opacity. Based on different sensitivity analysis, the retrieval procedure also requires to include as free parameters (1) the, dust effective radius; (2) the dust effective variance; and (3) the imaginary part of the refractive index of dust particles in UVA band. We found that the imaginary part of the refractive index of dust particles does not have a big impact on NIR signal, and hence we can kept constant this parameter in the retrieval of dust opacity at this channel. In addition to dust opacity measurements, this instrument is also capable to detect and characterize clouds by looking at the time variation of the color index (CI), defined as the ratio between the observations in NIR and UVA channels, during daytime or twilight. By simulating CI signals with a radiative transfer model, the cloud opacity and cloud altitude (only during twilight) can be retrieved. Here the different retrieval procedures that are used to analyze SIS measurements, as well as the results obtained in different sensitivity analysis, are presented and discussed."Publicación Restringido Greenhouse gases in the tall tower of El Arenosillo station in Southwestern Europe: First-year of measurements(Elsevier, 2024-01-06) Jose, Adame; Padilla, Rubén; Gutiérrez Álvarez, I.; Bogeat Sánchez-Piqueras, José Antonio; López, Alfonso; Yela González, MargaritaCarbon dioxide (CO2), methane (CH4) and carbon monoxide (CO) were measured at 10, 50 and 100 m in a tall tower located at El Arenosillo observatory (Southwestern Europe) from December 2021 to December 2022. Depending on the height, hourly averages varied between 418 ± 5 at 100 m and 422 ± 8 μmol mol−1 at 10 m for CO2, while CH4 varied between 1999 ± 30 nmol mol−1 at 100 m and 1986 ± 25 at 10 m and ∼ 102 ± 19 nmol mol−1 for CO. A monthly variation with a common maximum in January–February was obtained while the minimum was found in June for CH4 and CO, whereas the minimum for CO2 was in August. The seasonal daily patterns showed a maximum between 5:00 and 10:00 UTC while the minimum was observed at 15:00–18:00 UTC. The daily variations are controlled by atmospheric stability, photochemical activity and vegetation influence, among other factors. The CO2 gradient was strongly conditioned by the photosynthesis, plant and soil respiration and vertical mixing with peaks higher than 19 × 10−2 μmol mol−1 m−1 at ∼5:00 UTC in spring and autumn. The CH4 gradient, greater in winter and autumn (12–27 × 10−2 μmol mol−1 m−1) is affected by vertical stability, local emissions and photochemical activity while CO depicted small vertical gradients. A different behavior was found in the CO2 and CH4 gradients, for CO2 the 10–50 m gradient is higher than 50–100 m while CH4 was the opposite; which could reflect a lower CO2 surface layer than CH4. The observations at 100 m registered CO and CH4 peaks that were not recorded at 10 m, which could be associated with the arrival of a forest fire plume and potential CH4 fugitive emissionsPublicación Restringido OClO, NO2 and O3 total column observations over Iceland during the winter 1993/94(AGU Publishing, 1996-11-15) Gil, M.; Puentedura, O.; Yela González, Margarita; Parrondo, María Concepción; Jadhav, D. B.; Thorkelsson, B.Ground-based observation of OClO, NO2, and O3 columns by differential UV-Visible spectroscopy at twilight during the fall winter of 1993/94 at the sub-Arctic station of Reykjavik (64°N, 23°W) are presented. Results show no direct evidence of ozone depletion during the period but significant amounts of OClO were observed in December and January when NO2 abundances were at the annual minimum. NO2 columns are found to be controlled by the hours of light available but highly modulated by the lower stratosphere temperature. OClO was observed outside the vortex as well, but only at times when NO2 was low.
