Time-scale and extent at which large-scale circulation modes determine the wind and solar potential in the Iberian Peninsula

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.The North Atlantic Oscillation (NAO), the East Atlantic (EA) and the Scandinavian (SCAND) modes are the three main large-scale circulation patterns driving the climate variability of the Iberian Peninsula. This study assesses their influence in terms of solar (photovoltaic) and wind power generation potential (SP and WP) and evaluates their skill as predictors. For that we use a hindcast regional climate simulation to retrieve the primary meteorological variables involved, surface solar radiation and wind speed. First we identify that the maximum influence of the various modes occurs on the interannual variations of the monthly mean SP and WP series, being generally more relevant in winter. Second we find that in this time-scale and season, SP (WP) varies up to 30% (40%) with respect to the mean climatology between years with opposite phases of the modes, although the strength and the spatial distribution of the signals differ from one month to another. Last, the skill of a multi-linear regression model (MLRM), built using the NAO, EA and SCAND indices, to reconstruct the original wintertime monthly series of SP and WP was investigated. The reconstructed series (when the MLRM is calibrated for each month individually) correlate with the original ones up to 0.8 at the interannual time-scale. Besides, when the modeled series for each individual month are merged to construct an October-to-March monthly series, and after removing the annual cycle in order to account for monthly anomalies, these correlate 0.65 (0.55) with the original SP (WP) series in average. These values remain fairly stable when the calibration and reconstruction periods differ, thus supporting up to a point the predictive potential of the method at the time-scale assessed here

Sand invasion along the Portuguese coast forced by westerly shifts during cold climate events

Acceso restringidoPhases of higher aeolian activity are responsible for the formation and movement of large transgressive dunefields. Well-reported phases of aeolian activity in northwest Europe are coincident with global cooling events and were related to enhanced westerly winds and storminess. However, the extent to which these climatic episodes influenced dunefield dynamics in southwest Europe remains an open question. Ground penetrating radar (GPR) was used to image the stratigraphy of a cliff-top coastal transgressive dunefield in Portugal and reconstruct former windfield regimes. Using optically stimulated luminescence (OSL) five major phases of aeolian activity were dated at 12.6, 5.6, 1.2, 0.4 and 0.3 ka, and related to coastal instability and enhanced westerlies. These phases were later reconciled to favorable patterns of atmospheric circulation simulated by global and regional climate models at both synoptic and local scales, respectively. The results prove that major phases of aeolian activity in southwest Europe are associated with the onset of cold climate events of global distribution coinciding with aeolian accumulation in northwest Europe. This implies the dominance of zonal westerlies along the western coast of Europe from Denmark to Portugal during the onset of cold climate events. Model simulations suggest that the pattern of atmospheric circulation during periods of enhanced aeolian activity is compatible with prolonged negative phases of the North Atlantic Oscillation (NAO)

Impact of atmospheric circulation patterns on coastal dune dynamics, NW Spain

Dunes in temperate latitudes have experienced a significant stabilization in recent times, essentially as a consequence of the expansion of dense vegetation cover. Yet, the causes for this gradual stabilization as well as the causes promoting antecedent aeolian mobilization remain poorly understood. The Traba coastal dune field, located in NW Spain, was examined to explore the causes inducing aeolian activity and subsequent stabilization since 1940. Morphological changes were identified through the combination of aerial photographs and geophysical techniques. Local wind field regimes were simulated using a regional climate model to obtain the variability of the most relevant modes of atmospheric circulation in the North Atlantic and European regions; North Atlantic Oscillation (NAO), Eastern Atlantic (EA) and Scandinavian (SCAND). This allows us to identify the impact of these circulation modes over dune dynamics. Results document an episode of aeolian activity during the 1950s followed by a gradual stabilization and fixation of the dune coincident with a decrease on storm and wind intensity. Yet, aeolian sand movement remained active in small areas (blowouts), occurring mainly during the summer. NE winds associated with a negative phase of the EA explain the movement of sand within the dune field under favorable conditions of sand supply. On the other hand, sand supply to the dune field from the beach was promoted by NW winds coincident with the summer negative phase of NAO. During winter, the negative NAO favored frequent SW winds associated with the passage of intense storms, which in turn explain sand remobilization from the beach making sediment available for the NW winds to blow inland. With this work, it is proven that to understand past and future aeolian activity requires critical consideration of the variability and impact of the two principal modes of atmospheric circulation in the North Atlantic (NAO and EA). The SCAND mode explaining a lower percentage of the local wind field variability was also included to achieve higher significance levels of explained variance

Climatic characterization of heat waves in Brazil

De acordo com a última geração de modelos climáticos, a probabilidade de ocorrência de grandes ondas de calor nas próximas décadas tende a subir de forma significativa. Atualmente existem inúmeros estudos relativos a esta problemática no Hemisfério Norte, particularmente para a Europa e para a América do Norte, devido aos seus impactos significativos em áreas como a saúde, economia e agricultura. Em relação ao Hemisfério Sul e especialmente ao Brasil, este problema apresenta-se como uma questão ainda pouco desenvolvida, apesar da sua enorme área geográfica e população potencialmente afetada. Com este trabalho pretende-se realizar um estudo diagnóstico das ondas de calor observadas em algumas das grandes cidades brasileiras, incluindo a sua frequência, distribuição sazonal e evolução temporal desde a década de 1960. Os resultados obtidos evidenciam a presença de uma tendência positiva na frequência e duração das ondas de calor a partir de 1980, particularmente para as cidades de São Paulo, Manaus e Recife. Brasília registrou maior número de ondas de calor nas últimas décadas, enquanto o Rio de Janeiro apresentou o menor número de eventos. Quanto à variabilidade sazonal os meses de Outono/Inverno foram aqueles em que se verificou maior número de ondas de calor-----------------------------------------------------------Abstract According to the state-of-the-art global and circulation models the probability of occurrence of large heat waves in the following decades will increase significantly. Currently, due to their significant impacts in several socio-economic areas such as public health, energy production and consumption and agriculture, there are numerous studies for the Northern Hemisphere regions evaluating this problem. However, for the southern hemisphere and especially Brazil, a similar analysis is lacking, despite its huge geographical area and large population potentially affected. The main goal of this work is to provide a comprehensive diagnostic study of heat waves observed in several large Brazilian cities, including heat waves frequency, seasonal distribution and temporal evolution since the 1960s decade. In general, results indicate the presence of a positive trend in the frequency and duration of heat waves since the 1980s, with special emphasis to cities like São Paulo, Manaus and Recife. Brasília was the city that in the last decades recorded the highest number of heat waves while Rio de Janeiro was the city with the smallest number recorded. In respect to seasonal variability the Autumn/Winter months were the months with the largest number of heat waves recordedinfo:eu-repo/semantics/publishedVersio

ÍNDICE DE SUSTENTABILIDADE SOCIOAMBIENTAL NO ENSINO

Tomando por base o fato de que é das instituições de ensino que emergem os líderes do futuro, bem como o impacto que exemplos de atitudes sustentáveis podem trazer, este artigo propõe que as escolas dos mais diferentes tipos adotem em suas estruturas um índice de sustentabilidade socioambiental dedicado a aferir e estimular a prática da sustentabilidade. Para a composição desse índice, foram adotados seis indicadores: Consumo de Energia Elétrica; Consumo de Água; Consumo de Combustíveis; Grau de Conscientização no Uso do Papel de Escritório; Qualidade na Destinação de Resíduos; e Responsabilidade Social e Ambiental. A metodologia proposta foi testada e avaliada em caráter piloto no campus Maracanã do CEFET/RJ, com ano-base 2012. O Índice de Sustentabilidade Socioambiental, que pondera as possíveis desigualdades de indicadores tão distintos, registrou desempenho de 32,3% (ou 0,32), evidenciando que ainda há muito a ser feito quanto à sustentabilidade na instituição. Espera-se que instituições de ensino como o CEFET/RJ adotem a prática de medir seus esforços nesse campo, tornando cada vez mais robusta ferramentas de avaliação como a que se apresenta neste artigo, a qual integra as dimensões da sustentabilidade – ambiental, econômica e social – com a tríade da educação – ensino, pesquisa e extensão.DOI: 10.5902/198346591277

Drought impacts on vegetation activity, growth and primary production in humid and arid ecosystems

Ponencia presentada en: VIII Congreso de la Asociación Española de Climatología celebrado en Salamanca entre el 25 y el 28 de septiembre de 2012.[EN]We have evaluated the response of the Earth biomes to drought using a new global dataset that captures drought effects on vegetation at various time scales. We show that arid and humid biomes are both affected by drought, and that the time scale on which droughts most intensively affects vegetation plays a key role in determining the sensitivity of biomes to drought. Arid biomes respond to drought at short time scales because plants have mechanisms allowing them to rapidly adapt to changing water availability. Humid biomes also respond to drought at short time scales, probably because there plant species show a poor adaptability to water shortage. Sub-humid biomes respond to drought at long time scales because plants are adapted to withstand water deficit, but they lack the rapid post-drought recovery observed in arid biomes.[ES]En este trabajo se evalúa la respuesta de los diferentes biomas terrestre a la sequía mediante una base de datos nueva que captura el efecto de la sequía sobre la vegetación a diferentes escalas temporales. Se ha comprobado que los biomas característicos de zonas áridas y húmedas se ven afectados por la sequía, y que la escala temporal de la sequía juega un papel clave al determinar la sensibilidad de los biomas a la sequía. Los biomas áridos responden a las sequías medidas a escalas temporales cortas, debido a que las plantas tienen mecanismos que les permitan adaptarse rápidamente a la disponibilidad de agua. Los biomas húmedos también responden a la sequía a escalas temporales cortas, probablemente debido a que las especies ubicadas allí muestran una mala adaptación a la escasez de agua. Los biomas subhúmedos responden a la sequía a escalas de tiempo más largas, porque las plantas están adaptadas para soportar el déficit de agua, pero carecen de la rápida recuperación observada tras la sequía en los biomas áridos.This work was supported by projects financed by the Spanish Commission of Science and Technology (CGL2011-27574-CO2-02, CGL2011-27536 and CGL2011-26654) and the Aragón Government. J.J.C. thanks the support of ARAID and A.S-L. was supported by a postdoctoral fellowship from the Generalitat de Catalunya (2009 BP-A 00035)

The interannual variability of global burned area is mostly explained by climatic drivers

Better understanding how fires respond to climate variability is an issue of current interest in light of ongoing climate change. However, evaluating the global?scale temporal variability of fires in response to climate presents a challenge due to the intricate processes at play and the limitation of fire data. Here, we investigate the links between year-to-year variability of burned area (BA) and climate using BA data, the Fire Weather Index (FWI), and the Standardized Precipitation Evapotranspiration Index (SPEI) from 2001 to 2021 at ecoregion scales. Our results reveal complex spatial patterns in the dependence of BA variability on antecedent and concurrent weather conditions, highlighting where BA is mostly influenced by either FWI or SPEI and where the combined effect of both indicators must be considered. Our findings indicate that same-season weather conditions have a more pronounced relationship with BA across various ecoregions, particularly in climatologically wetter areas. Additionally, we note that BA is also significantly associated with periods of antecedent wetness and coolness, with this association being especially evident in more arid ecoregions. About 60% of the interannual variations in BA can be explained by climatic variability in a large fraction (-77%) of the world's burnable regions.A.G. thanks the Ministerio de Ciencia, Innovación y Universidades of Spain for PhD contract FPU19/06536 and extends his thanks to the Instituto Dom Luiz for its close collaboration during her stay in Lisbon. A.G., M.A.T-V., S.J., and M.T. acknowledges the support of the ONFIRE project, Grant PID2021-123193OB-I00, funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe.” M.T. acknowledges funding by the Spanish Ministry of Science, Innovation, and Universities through the Ramón y Cajal Grant Reference RYC2019-027115-I. S.J. acknowledges funding by the Spanish Ministry of Science, Innovation, and Universities through the Ramón y Cajal Grant Reference RYC2020-029993-I

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio