A story of dust and ice: Constraining dust-driven immersion freezing in climate models using spaceborne retrievals

Clouds and aerosols impact the Earth’s thermostat and precipitation. There is increasing evi- dence that dust aerosol frequently controls cloud glaciation, modifying clouds’ radiative eect and response to global warming. For realistic climate change projections, it is crucial to improve the simulated pathway between dust immersion freezing and cloud glaciation. However, current freezing schemes, which extrapolate laboratory results to larger atmospheric scales, are poorly constrained. Based on spaceborne observations of cloud-phase and aerosols, we explore whether dust-driven immersion freezing can be improved in a climate model so that the climate impact of dust ice-nuclei can be estimated more accurately. Combining an aerosol model reanalysis with spaceborne retrievals of cloud phase, we estimated the global co-variability between mineral dust aerosol and cloud glaciation. Relying on a spaceborne lidar, a lidar-radar synergy, and a radiometer-polarimeter synergy, we also locate and quantify the hemispheric and seasonal con- trast in cloud-phase. Finally, we use these estimations to refine the dust-driven droplet freezing in a climate model. Our results show that observations of cloud-top phase contrasts may be used to evaluate dust-driven droplet freezing in climate models. In the extratropics, the average frequency of ice cloud increases by +5% to +10% for higher mineral dust mixing-ratios on a day-to-day basis. For similar mixing-ratios of mineral dust, we found that the ice frequency can still vary between latitudes, especially between Hemispheres and between mid- and high-latitudes. By using only retrievals for which satellite products agree on cloud-phase, we find that the cloud-phase transition from liquid to ice occurs within a narrower temperature range. This suggests that individual products tend to classify too many clouds as liquid for temperatures below -30°C and too many as ice for temperatures above -10°C. At -30°C, the hemispheric and seasonal contrasts — relative to the Southern Hemisphere and boreal spring, respectively — lie between +21% to +39% for individual cloud- phase products and between +52% to +75% for a combination of products. We use these contrasts to tune the dust ice-nuclei eciency in the model, limiting their eect during clean conditions. Consequently, the model agrees better with the estimated cloud-top-phase contrasts and a dust-driven glaciation eect of 0.14 ± 0.13 W m^2 in the Northern Hemisphere, which is lower than previously assumed. These changes are associated with a decrease in the cloud liquid water path and a weak enhancement of the stratiform precipitation at the expense of convective precipitation. Our results show that observations of cloud-top phase contrasts may be used as a constraint for dust-driven droplet freezing in climate models. Thus, our constraining approach may help to achieve more accurate climate predictions and direct future climate model development.Wolken und Aerosole beeinflussen den Energiehaushalt und den Wasserkreislauf der Erde. Es gibt zunehmend Hinweise darauf, dass Staubaerosol die Vereisung von Wolken, ihren Strahlungsef- fekt und ihre Antwort auf die globale Erwärmung beeinflusst. Um den Klimawandel genauer zu projizieren, ist es daher wichtig, den Weg von staubinduzierten Gefrierprozessen zur Vereisung der Wolken besser zu simulieren. Gegenwärtige Gefrierschemen, die von Laborergebnissen auf gröbere atmosphärische Skalen extrapolieren, sind jedoch limitiert in ihrer Anwendbarkeit. Basierend auf Satelliten-Beobachtungen von Wolkenphasen und Aerosolen wird in dieser Ar- beit untersucht, wie das staubbedingte Gefrieren in Klimamodellen verbessert werden kann, um Klimaeekte von Staubeiskeimen genauer abschätzen zu können. Zu diesem Zweck wer- den Reanalyse-Daten eines Aerosolmodells mit dem Satelliten-Beobachtungen von Wolkenphase kombiniert und die globale Kovariabilität zwischen Mineralstaubaerosol und Wolkenvereisung abgeschätzt. Basierend auf einem weltraumgestützten Lidar, einer Lidar-Radar Kombination und einer Radiometer-Polarimeter Kombination werden hemisphärische und saisonalen Kon- traste in der Wolkenphase lokalisiert und quantifiziert. Schließlich werden diese Schätzungen verwendet, um den Einfluss des Mineralstaubes auf das Gefrieren von Wolkentröpfchen in einem Klimamodell einzugrenzen. Die vorgelegten Ergebnisse zeigen, dass Beobachtungen des Kon- trastes in der Wolkenphase dafür verwendet werden können, das staubgetriebene Gefrieren von Wolkentröpfchen in Klimamodellen zu optimieren. In den Extratropen steigt die durchschnittliche Häufigkeit von Eiswolken für höhere Mineralstaub- Mischungsverhältnisse um +5% bis +10%. Bei ähnlichen Mischungsverhältnissen von Min- eralstaub kann die Häufigkeit von Eiswolken für verschiedene Breiten immer noch variieren. Einzelne Wolkenphasen-Produkte neigen dazu, zu viele Wolken als flüssig für Temperaturen unter -30°C und zu viele als Eis für Temperaturen über 10°C zu klassifizieren. Bei -30°C liegen die hemisphärischen und die saisonalen Kontraste — relativ zur südlichen Hemisphäre bzw. zum borealen Frühjahr — zwischen +21% und +39% für einzelne Produkte in der Wolken- phase und zwischen +52% und +75% für eine Kombination der Produkte. Diese Kontraste wurden verwendet, um die Ezienz der Staubeiskeime im Modell zu optimieren. Nach er- folgter Optimierung stimmt das Modell besser mit den aus Beobachtungen der geschätzten Kontraste in der Wolkenphase überein und zeigt einen staubbedingten nordhemisphärischen Netto-Strahlungseekt von 0.14 ± 0.13 W m^2 durch die Vereisung, der niedriger ist als bisher angenommen. Diese Änderungen sind mit einer Abnahme der Gesamtwassermenge in den Wolken und einer Verstärkung des stratiformen Niederschlags auf Kosten des konvektiven Niederschlags verbunden

Análisis económico-financiero del Grupo DIA: estudio de las principales claves explicativas de su actual crisis

En este Trabajo Fin de Grado se realiza un estudio de la crisis en la que se encuentra inmersa, desde los últimos meses, el grupo de distribución alimentaria DIA. A partir de la información económico-financiera facilitada por la compañía y de otras muchas fuentes económicas, se ha pretendido, primeramente, plasmar la situación de DIA con carácter previo al estallido de la crisis, y, a continuación, poner en evidencia las claves principales que han tenido una mayor determinación en la actual situación de grave crisis que atraviesa el grupo DIA.Universidad de Sevilla. Doble Grado en Derecho, Finanzas y Contabilida

Investigation of atmospheric conditions fostering the spreading of legionnaires’ disease in outbreaks related to cooling towers

Legionnaires’ disease (LD) is a severe lung infection caused by the bacteria Legionella pneumophila which is usually associated with water managing installations like cooling towers. Several outbreaks of LD have been linked to individual sources of bioaerosol in the past. However, the transmission pathways as well as the influence of meteorological factors in the spreading of such bioaerosols remain unclear. Using the meteorological data near 12 LD outbreaks in Europe for the period 2000–2016, the correlation between key meteorological factors and the occurrence of LD was assessed. Temperature, humidity, atmospheric pressure, wind speed, precipitation, cloud cover and, for the first time, fog occurrence were included as potential risk factors. It was found that the occurrence of fog was related to four of the LD outbreaks, suggesting that the presence of fog droplets and/or the thermal inversions associated with fog may play a role in the disease spreading. This finding can contribute to outbreak investigations and to the prevention of future outbreaks. © 2019, The Author(s)

Biotecnología Moderna para el Desarrollo de la Agricultura en Colombia

Colombia is currently one of the most promising countries with regard to its potential for agricultural development and for generating food supply for current and future human generations. This is owing to factors such as availability of land, water, topographical diversity, as well as political factors. Nevertheless, Colombia will reach this full potential if it adopts available technologies that can meet the current global challenges faced by the agriculture in the 21st century: among others, world population growth, increase in average life expectancy, high degree of malnutrition, climate change, wrong agricultural practices. Here is presented how modern biotechnology is an important ally as a wide range of technologies and innovative systems can be applied where they are most needed: for increasing cultivation productivity, resisting both biotic and abiotic factors, and ensuring food safety. In this study is showed evidence with regard to significant benefits of adopting biotechnological crops to contribute to food safety and how they are already being implemented in both developed and developing countries. Using modern technology, there are open opportunities for the country in search of circular bio-based economy, strengthen its food sovereignty and to serve as an agricultural breadbasket to Latin America and the World.Colombia es actualmente uno de los países más prometedores en cuanto a su potencial para el desarrollo agrícola y para generar alimentos para las generaciones humanas actuales y futuras. Esto se debe a factores como la disponibilidad de tierra, agua, diversidad topográfica, así como a factores políticos. Sin embargo, Colombia alcanzará su pleno potencial de desarrollo agrícola sostenible si adopta las tecnologías disponibles que puedan hacer frente a los desafíos globales actuales que enfrenta la agricultura en el siglo XXI: entre otros, el crecimiento de la población mundial, el incremento en el promedio de la esperanza de vida, alto grado de desnutrición, cambio climático, uso de practicas agrícolas equivocadas. Aquí es presentado cómo la biotecnología moderna es un aliado importante ya que se puede aplicar una amplia gama de tecnologías y sistemas innovadores donde más se necesitan: aumentar la productividad y sostenibilidad del cultivo, resistir los factores de estrés bióticos y abióticos y garantizar la seguridad alimentaria. En este estudio se muestra evidencia sobre los beneficios significativos de la adopción de cultivos biotecnológicos para contribuir a la inocuidad de los alimentos y como ellos ya se están implementando en los países desarrollados y en vía de desarrollo. Usando tecnologías modernas, hay oportunidades abiertas para el país en la búsqueda de una economía circular de base biológica, que fortalezca su soberanía alimentaria y para servir como despensa agrícola para América Latina y el mundo

Genetic Improvement of Oilseed Crops Using Modern Biotechnology

In 2009, big challenges facing the agricultural sector in the twenty-first century were presented to the world. Human population growth, increased life expectancy, loss of biodiversity, climate change and accelerated land degradation are the main factors contributing to rethink agriculture system production. In that scenery, modern biotechnology has set a stage for the advancement of agricultural practices and it is clearly an important ally to apply a broad array of technologies and innovative systems where they are most needed, such as enhancing crop productivity, increasing yields, and ultimately ensuring food security. One of the biggest challenges is related to technify production systems, but with no doubt, developing genetic improvement toward getting an efficient and sustainable agriculture, generating new seed qualities (new traits), such as, among others, to upset fatty acids content in oilseed crops have been growing up significantly due to industry interest. In this study, a review about the main advances in genetic improvement of some oilseed crops, starting with omics to understand metabolic routes and to find out key genes in seed oil production, and also, getting in use of modern biotechnology to alter the production of fatty acids, and to face biotic challenges in oilseed crops is presented

Molecular replication using covalent base-pairs with traceless linkers.

A unique feature of kinetically inert covalent base-pairing is that the nature of the chemical information that is transferred can be modulated by changing the chemical connectivity between the two bases. Formation of esters between phenols and benzoic acids has been used as a base-pairing strategy for sequence information transfer in template-directed synthesis of linear oligomers, but the copy strand produced by this process has the complementary sequence to the template strand. It is possible to form a base-pair between two benzoic acids by using a hydroquinone linker, which is eliminated when the product duplex is hydrolysed. Using this approach, covalent template-directed synthesis was carried out using a benzoic acid 3-mer template to produce an identical copy. This direct replication process was used in iterative rounds of replication leading to an increase of the population of the copied oligomer.Engineering and Physical Sciences Research Council (EP/P027067/1

A construction as a frontier of form: the labyrinth of André Bloc in Carboneras

El polifacético arquitecto de origen argelino André Bloc, tras ensayar en varias ocasiones en su jardín de Meudon algunas soluciones plásticas habitables, insertó una de sus esculturas habitáculo en una de las playas almerienses de Carboneras. La construcción, conocida popularmente como ‘El Laberinto’, constituye una obra singular del patrimonio arquitectónico español del siglo pasado y una muestra ejemplar del esfuerzo de integración entre arte y arquitectura. Pero sobre todo, esta insólita vivienda supone un testimonio extraordinario respecto a la frontera que separa arte y arquitectura y restringe una hipotética coalescencia entre ambas: el hecho constructivo marca un límite que, aunque variable, resulta ineludible.After trying some habitable, sculptural solutions in his garden at Meudon, on several occasions, the multifaceted architect of Algerian origin, André Bloc, built one of his habitable sculptures at one of the beaches of Carboneras, in Almeria. The construction, popularly known as “The Labyrinth”, constitutes a unique work from the Spanish architectural heritage of the last century and is a prime example of the force of integration between art and architecture. However, above all, this unusual house represents an extraordinary testimony with respect to the frontier that separates art and architecture and which restricts a hypothetical coalescence between both; the constructive fact defines a boundary which, although variable, is inescapable

The GATEPAC chair: a collective journey there and back again

Como resultado crítico derivado de la valoración del mueble entre 1880 y 1930, el GATEPAC estableció algunos parámetros definitorios irrenunciables que condicionaban la determinación del mobiliario moderno —honestidad, coherencia y función, principalmente—, y que estaban en consonancia con las ideas defendidas por arquitectos teóricos relevantes del periodo. Respondiendo a estos tres aspectos básicos, el grupo elaboró una caracterización del mueble moderno, el cual, a su juicio, debía ser: simple, ligero, transportable, higiénico y estándar. Conforme a estos aspectos, los arquitectos del GATEPAC desarrollaron desde finales de los años 20 y hasta 1936 un conjunto de sillas estándar que sirvieron como objeto de experimentación de las reflexiones del grupo. Estas piezas sufrieron una evolución desde el mueble de acero hasta el mueble de madera y mimbre —el mueble popular. En este desarrollo permanecieron vigentes los principios alcanzados en la modernidad, pero las formas y materiales fueron transformados. Es en estos últimos aspectos donde ese progreso puede entenderse como una evolución inversa en la que, una vez conseguida la liberación del mobiliario de lo decorativo e inútil, se regresa hacia unas formas y materiales propias del universo popular.As a critical result of furniture valuation between 1880 and 1930, the GATEPAC group set a number of invariable parameters that conditioned the definition of modern furniture (honesty, consistency and function were the primary values), in line with the ideas advanced by significant architecture theorists at that time. In light of these three basic criteria, the GATEPAC group developed a view of modern furniture as being simple, lightweight, portable, hygienic and standard. In line with these criteria, the GATEPAC architects experimented with the production of a standard set of chairs between the late 1920s and 1936. These pieces evolved from steel to wood and wicker design — popular furniture. Although the established principles of modernity were retained in this development process, the forms and materials were transformed. It is in relation to the latter that progress may be read as a form of reversed evolution, whereby no longer required to be merely decorative and useless, furniture design was free to return to forms and materials of the popular domain

El proyecto arquitectónico como impulso del mobiliario estándar

[EN] In the 1920s the architect takes on a special role in the furniture scene. Faced with the need to equip their works with standard furniture, appropriate to the new architecture, he finds in the interior a field for thedevelopment of their work. It is precisely in the performance of their work as architects that the new types of furniture emerge: standard pieces that, paradoxically, are born from integral architectural projects. It is thenwhen the written media of the time presented a debate, both outside and within Spain, about the limits of thearchitectural project and the role of the architect in the design of furniture. In this context, several Spanisharchitects, such as C. Arniches and M. Domínguez, L.M. Feduchi, L. Gutiérrez Soto, and J.M. Aizpurúa andJ.Labayen, contribute their visions from a theoretical point of view, but also through their built work, constitutingthemselves as examples of this phenomenon that gave rise to integral architectural works and standard pieces inthe same project. By analyzing the contents of Spanish architectural magazines of the time and other specializedwritings, this article aims to shed light on the role of the architectural project as an impulse for the developmentof modern standard furniture.[ES] En la década de 1920 el arquitecto adquiere especial protagonismo en la escena del mueble. Ante la necesidad de equipar sus obras con mobiliario estándar, adecuado a la nueva arquitectura, encuentra en el diseño del interior un campo de desarrollo de su labor. Precisamente es en el desempeño de su trabajo como arquitectos donde surgen los nuevos tipos de muebles: piezas estándar que, paradójicamente, nacen de proyectos de arquitectura integral. Es entonces cuando los medios escritos del momento presentan un debate, sobre los límites del proyecto arquitectónico y el papel del arquitecto en el diseño del mueble. En este contexto, varios arquitectos españoles, como C. Arniches y M. Domínguez, L.M. Feduchi, L. Gutiérrez Soto o J.M. Aizpurúa y J. Labayen, aportan sus visiones desde el plano teórico, pero también a través de su obra construida, constituyéndose como ejemplos de este fenómeno que dio lugar a obras de arquitectura integrales y piezas estándar en un mismo proyecto. Mediante el análisis de los contenidos de las revistas españolas de arquitectura de la época, así como de otros escritos especializados, el artículo persigue arrojar luz sobre el papel del proyecto arquitectónico como impulso del desarrollo del mueble estándar moderno.Villanueva Fernández, M.; García-Diego Villarías, H. (2022). The architectural project as an impulse for standard furniture. VLC arquitectura. Research Journal. 9(2):7-37. https://doi.org/10.4995/vlc.2022.166637379

LBT House 1961: Built Concrete Art

[Resumen] El artículo explora la operatividad de los principios gráfi cos del Arte Concreto en la aplicación a un proyecto real de arquitectura. Para ello, se utiliza el ejemplo de la casa de Lanfranco Bombelli proyectada por él mismo y situada en Cadaqués en 1961. La obra da muestra de un ensayo cabal de arquitectura doméstica que se nutre de algunas nociones gráfi cas precisas que se desprenden de su fi lia personal hacia esta corriente artística. Se trata ésta de una manera de afrontar la tarea artística que presenta ciertas similitudes con la manera de afrontar el proyecto de arquitectura. Y de ahí que la Casa LBT presente experimentalismo plástico palpable, que sin embargo se imbrica con una sofi sticada relectura de los lenguajes que es sensible con la tradición local.[Abstract] The article explores the operability of the graphic principles of the Concrete Art in its application to a real architecture project. To achieve this goal, the text uses the example of Lanfranco Bombelli’s own house, designed by him in 1961and located in Cadaqués. Th e work demonstrates how domestic architecture can draws on notions of graphics. Actually, Concrete Art presents certain similarities in way of dealing with the project of architecture. And that is why the plastic experimentalism of the LBT house is palpable, yet overlaps with a sophisticated reading of the local tradition languag