Browsing by Issue Date, starting with "2022-12-23"
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- Critical analysis of CMIPs past climate model projections in a regional context: The Iberian climatePublication . Soares, Pedro M.M.; Lemos, Gil; André Lima, Daniela CatarinaThe Iberian Peninsula is a known climate change hotspot. In the last decades, the Coupled Model Intercomparison Project (CMIP) has allowed for thousands of Global Climate Model (GCM) simulations to be conducted, an important tool to assess and understand future changes in Earth's climate. The comparison of past future projections with observations provides a robust evaluation of the models’ skill according to different emission scenarios. Here, a comprehensive performance assessment of GCM-simulated mean, maximum, and minimum temperatures, and accumulated precipitation is conducted for Iberia, by retrospectively comparing historical simulations and past future projections from CMIPs 1 to 6 with reference datasets. From means to extremes, and multi-year intra-annual cycles to inter-annual trends, GCM simulations are compared with Iberia0.1 and E-OBS observational gridded datasets, and ERA5 reanalysis. The matching between the variables’ distributions is assessed through the distribution added values (DAVs), a measure of gain or loss in performance between CMIPs. Results show relevant improvements in the description of the Iberian climate throughout the CMIP effort, for historical and past future periods. While the representation of intra-annual cycles (inter-annual trends) is enhanced after CMIP3 (CMIP2), GCMs from all CMIPs are generally able to depict the observed warming trend. Nevertheless, until 2021, a slight detrimental effect in the performance of CMIP6 models is found, in comparison with CMIP5 ones, with positive DAVs obtained only for past future temperature projections (less than 2%). A continuous monitorization of modelling accuracy for Iberia is needed, considering the increasing relevance of climate change information for adaptation strategies.
- O quaijo que xerava bem um estudo de produções escritas e orais do ditongo de crianças de dois dialetos portuguesesPublication . Rodrigues, Celeste; Gomes, JéssicaIn an early stage of learning to write, diphthongs are complex structures that cause difficulties for many children. In addition to having a two-character representation, diphthongs have different phonetic forms that seem to interfere with children’s consolidation of the conventional spelling, depending on whether their dialect more or less resembles the graphic form of the structure. Based on the idea that, unlike the northern dialect, the southern dialect produces the diphthong /eI/ as [e], the goal of the present paper is to analyze the behavior of children from Alentejo and Trás-os-Montes (from Elvas (E), Vila Nova de Santo André (VNSA), Bragança (B) and Chaves (Ch)) from the 2nd year of schooling regarding this structure. It is also known that /eI/ centralization occurs in some regions beyond Lisbon, and its effect on children’s writing outside the capital is unknown. As such, written productions from the mentioned localities will be observed in order to compare the results with those from Lisbon (L) and Porto (P) of the same diphthong, reported by Rodrigues & Lourenço (2017). Our results concerning writing indicate that children from the South of the country (L, E + VNSA) have more difficulty in stabilizing the spelling of the diphthong than children from the North (P, B + Ch). The order of the hit rates is as follows: P >> B + Ch >> E + VNSA >> L, which confirms the existence of possible effect of dialect on the spelling performance of these children. The non-conventional forms (FNCs) varied according to dialectal region. In the two Alentejo localities, there was a preference for the erroneous forms <*e>/<*é> and <*ai>, which allows us to hypothesize that, in addition to the to the single vowel [e] form already described by dialectal studies, the oral form [ɐj] is also present there. In turn, in the localities of Bragança and Chaves, the FNC <*ai> was the most frequent, suggesting that the pronunciation in this region may be [ɐj] in addition to [ej]. Only the oral productions of the students who presented FNCs were analyzed, to try to understand whether the FNCs adopted derived from a direct transposition from their orality to writing. The observed orality data revealed that (i) there are children who establish a direct relation between oral form produced and FNC adopted, (ii) there are children whose oral and written production have no relation, thus, there is no transposition in writing of the oral form and, finally, (iii) there are children whose production in writing and/or orality varies depending on the lexical item. These results suggest that the analysis of children’s writing and speech may be a way to discover new clues for the development of other sociolinguistic work on Portuguese.
- Impact of the altitude on the wood anatomical traits of Calluna vulgarisPublication . Costa, Inês Boal Afonso de Oliveira; Nabais, Cristina; Caldeira, Maria da ConceiçãoClimate change scenarios for the Iberian Peninsula forecast an increase in temperature and a considerable decline in precipitation for all seasons. Heat waves, floods, and other extreme events can be expected to challenge the ability of several species to survive the new environmental trends. Calluna vulgaris (L.) Hull is a small to medium-sized evergreen woody shrub, with a large geographical distribution, being able to survive freeze conditions below −20°C in Mediterranean climates. Probably C. vulgaris presents a high genetic diversity and/or a high morphological and physiological plasticity, translated in a high degree of adjustment to different climatic conditions. To understand if C. vulgaris has high morphological plasticity, woody stems were collected from populations located at different altitudes in Serra da Estrela. The altitudinal gradient was used as a proxy for changing temperature. Several wood anatomical traits were measured: shrub-ring width (SRW), average vessel area (AVA), and percentage of cell wall (PCW). SRW was correlated with the prevalent climatic conditions. SRW from all populations showed a negative correlation with the summer temperature. Populations from lower altitudes showed a positive correlation with the minimum temperature of January, while the populations from higher altitudes showed a positive correlation with precipitation from May to September. The SRW, AVA, and PCW from 2016 to 2020 showed no significant differences between the populations. The measured wood anatomical traits showed no significant differences with altitude, indicating that they are highly conserved, independent of the climatic conditions, or have a limited value as an adaptive trait. However, growth response to climatic conditions was slightly different between low and high-altitude populations of C. vulgaris, indicating adjustments in the response to the prevalent climatic conditions. Besides these results, more studies are necessary to understand shrub growth dynamics and adaptive traits, especially under scenarios of climate change.