Analysis of the Future of Hydropower Technologies in the European Union using Project Drawdown Framework

Climate change is an undeniable problem, and the solutions available to fight it need to be deeply understood. Along with other institutions, Project Drawdown is one of the leading fronts in research and resources about climate solutions. Its global analysis in 2017 and 2020, followed by regionalization efforts in the US and Europe, are critical pieces of this understand-ing and contextualization of climate change solutions in multiple sectors. This study aims to understand the contribution that large and small hydropower solutions can have in climate change mitigation in Europe and EU, specifically in reducing greenhouse gas (GHG) emissions, associated costs and its role in future developments of the electricity generation industry, one of the biggest GHG emitters. The methodology is supported by extensive data collection of electricity generation pro-jections (TWh) and key characteristics of the hydropower technologies. The results show that the electricity generated in Europe will grow in every studied scenario. However, the extent of this growth varies a lot along with the different scenarios from the various publications due to different models used, main socio-economic and technological assumptions. When it comes to the portion of that generation that is accomplished by hydropower, the results show a trend of stabilization or slight growth in some scenarios, with the future of these technologies laying essentially in repowering and improvements in existing powerplants and not in the building of new ones. Environmentally and financially, the findings suggest that large hydropower can bring a reduction of emissions between 1,8-2,5 Gt of CO2eq in its most likely scenarios with average savings in O&M and from lack of fuel costs close to 253 billion euros, while small hydro can contribute with a reduction of up to 0,9 Gt of CO2eq but presenting a net cost of about 300 billion euros, in comparison with the implementation of conventional technologies. At the same time, showing the need for improvement of the technology for it to play a significant role in climate change mitigation in the region.As alterações climáticas são um problema inegável e, as soluções disponíveis para as resolver têm que ser entendidas profundamente. A par de várias instituições, o Project Drawdown é uma das principais entidades em termos de investigação e recursos relativos a soluções climáticas. As suas análises globais realizadas em 2017 e 2020, seguida pelos trabalhos de regionalização nos E.U.A e Europa são peças fundamentais deste entendimento e contextualização de soluções para as alterações climáticas em vários setores. Este trabalho procura compreender a contribuição que as grandes e pequenas centrais hídricas podem ter na mitigação das alterações climáticas na Europa, particularmente na redução de emissões de gases com efeito de estufa (GEE), quais custos associados e o seu papel no setor da geração de eletricidade até 2050. A metodologia é baseada numa extensa compilação de projeções de geração de eletricidade (TWh) e características fundamentais das tecnologias hídricas. A modelação efetuada foi suportada no modelo bottom up Drawdown RRS, onde as soluções de tecnologia de geração hídrica foram individualmente modeladas para vários cnarios de adoção futura. Os resultados mostram que a eletricidade gerada na Europa e União Europeia irá crescer em todos os cenários analisados. No entanto, este acréscimo varia consideravelmente nos diferentes cenários devido aos modelos e pressupostos socio-económicos e técnicos usados em cada publicação analisada. No que diz respeito à quantidade dessa geração assegurada por hídricas, os resultados mostram uma tendência de estabilização ou, em alguns casos, um pequeno crescimento, com o futuro da tecnologia assentando essencialmente na atualização e melhoria de centrais já existentes e não na construção de novas infraestruturas. Em termos ambientais e económicos, os resultados indicam que a grande hídrica pode trazer uma redução de emissões potencial entre 1,8-2,5 Gt of CO2eq, nos seus cenários mais prováveis, estando esta redução de emissões ligada a uma poupança média ao longo do seu tempo de vida, em O&M e combustível, na ordem dos 253 mil milhões de euros, quando comparado com a utilização de combustíveis fósseis para geração eletricidade. Enquanto isto, a pequena hídrica terá o potencial para uma redução de emissões até 0,9 Gt of CO2eq apresentando, no entanto, uma perda monetária que ronda os 300 mil milhões de euros até 2050, face às tecnologias convencionais, ilustrando a necessidade de investigação e melhorias na tecnologia se for pretendido que esta seja uma tecnologia principal na luta contra as alterações climáticas na região

Detrital provenance of the Upper Triassic siliciclastic rocks from southwest Iberia: a review

In southwestern Iberia the Upper Triassic successions of Lusitanian, Alentejo and Algarve basins records the fragmentation of Pangaea in Permian–Triassic during which the paleogeography of Iberia was dominated by a series of coalescing, alluvial–deltaic wedges and axial braided rivers. In this study, we discuss the potential sediment sources of the Lusitanian, Alentejo and Algarve basins based on detrital zircon-age spectra, suggesting that Iberia occupied a central position Iberia in Pangaea during late Triassic. Conventional sedimentary petrography and paleocurrent measurements of previous works was combined with recently published detrital zircon U–Pb geochronology of the Upper Triassic siliciclastic rocks of southwest Iberia to shed light on the detrital provenance record. Zircon age populations found in the Upper Triassic strata of the Lusitanian, Alentejo and Algarve basins is dominated by Neoproterozoic (33–76%) and Paleoproterozoic (12–15%) grains. The most important differences are the dominance of Devonian–Carboniferous (33%) zircon in the Alentejo basin and the greater representativeness of Permian–Carboniferous (6%) zircon in the Lusitanian basin. The deposition in these Upper Triassic basins of Portugal is marked by variability in sedimentary sources, involving the denudation and local-scale directions of sediment transport from the Iberian basement with possible additional supplies derived from outside present-day Iberia. The Upper Triassic successions evolved separately with the detrital transport being probably controlled by local drainage systems, and occupying a central position in Pangaea just before the opening of the Central Atlantic Ocean

Strike-slip shear zones of the Iberian Massif: Are they coeval?

Strike-slip shear zones of the Variscan orogen are used to derive the evolution of paleostrain and discuss the kinematics of the waning stages of the Gondwana-Laurussia collision during the amalgamation of Pangea. In the Iberian Massif, the recognition of three late Carboniferous deformation events related to strike-slip tectonics (D3, D4, D5) in the Trancoso-Pinhel region (Portugal) reveals that late orogenic transcurrent deformation was episodic and occurred in a short period of time (<15 m.y.). Early stages of strike-slip deformation included dextral and sinistral shear zones and orogen-parallel upright folds (D3; ca. 311 Ma). These structures followed the development of extensional shear zones (D2) during the tectonothermal reequilibration of the orogen. D3 structures were deflected and folded by the sinistral D4 Juzbado-Penalva do Castelo shear zone, dated as ca. 309–305 Ma by SHRIMP (sensitive high-resolution ion microprobe) U-Pb zircon dating of synkinematic granitoids. D3 and D4 structures were folded under east-west compression (D5) influenced by the strike-slip movement of the dextral Porto-Tomar shear zone. Variscan movement along the Porto-Tomar shear zone started ca. 304 Ma (onset of the Buçaco basin and syn-D5 granites), but ceased before ca. 295 Ma (age of the final closure of the Ibero-Armorican arc and crosscutting granites). The contrasting geometry, kinematics, and timing of these strike-slip shear zones are explained by deformation partitioning upon a rheologically inhomogeneous crust with structural and tectonothermal anisotropies generated during previous deformation. The convergence vector between Gondwana and Laurussia during D3–D5 remained the same, and was equivalent to the vector that explains the previous tectonic record (D2) in central and northwestern Iberia

Coeval interaction between magmas of contrasting composition (Late Carboniferous-Early Permian Santa Eulália-Monforte massif, Ossa-Morena Zone): field relationships and geochronological constraints

The Santa Eulália-Monforte massif is a post-kinematic late Carboniferous-early Permian (LC-EP) located in the Ossa-Morena Zone (Portugal). This paper examines field relationships between calc-alkaline pinkish granites and mafic-intermediate rocks from the external ring of this composite massif and presents new U-Pb zircon age determinations. The estimated 206Pb/238U ages of 297.4 ± 4.2 Ma for a sample of the calc-alkaline pinkish granite and of 303.1 ± 3.1 Ma for a sample of gabbro-diorite, point to a short time interval between the crystallization of both magmas, with the mafic and intermediate rocks being the oldest ones. At the outcrop scale, contacts of the mafic-intermediate rocks with the host pinkish granite are sharp and corroborate this age relationship, but do not justify why the host-enclave contacts often have curved and irregular shapes, indicative of liquid-liquid interaction. A full analysis of the distribution of U-Pb zircon ages and respective Th/U ratios seems to be possible to admit that the distinct compositionally magmas were roughly contemporaneous. The ages obtained are also important because they fit the LC-EP Iberian calc-alkaline suite formed within the time interval in which the Iberian-Armorican Arc was formed, developed and took place the subduction of the Paleotethyan oceanic plate under the Eurasian active margin. Taking this geodynamic setting as reference, the LC-EP Iberian calc-alkaline magmatism can be interpreted as most probably related to the Cimmerian cycle instead of the traditionally accepted model that ascribe a closer connection with the Variscan cycle

Changing Carboniferous Arc Magmatism in the Ossa-Morena Zone (Southwest Iberia): Implications for the Variscan Belt

This work was supported by the financial support of the Portuguese Foundation for Science and Technology project UIDB-04683-2020-ICT and by the Spanish Research Agency, grant PGC2018-096534-B-I00 IBERCRUST.Carboniferous magmatism in southwestern Iberia was continuously active for more than 60 m.y. during the development of the Appalachian-Variscan belt of North America, North Africa and Western-Central Europe. This collisional orogen that records the closure of the Rheic Ocean is essential to understanding the late Paleozoic amalgamation of the Pangea supercontinent. However, the oblique convergence between Laurussia and Gondwana that lasted from the Devonian to the Carboniferous was likely more complex. Recently, a new tectonic model has regarded the Iberia Variscan belt as the site of coeval collisional and accretionary orogenic processes. Early Carboniferous plutonic rocks of southwest Iberia indicate arc magmatism in Gondwana. The Ossa-Morena Zone (OMZ) acted as the upper plate in relation to the geometry of the Paleotethys subduction. This active accretionary-extensional margin was progressively involved in a collisional phase during the Late Carboniferous. Together, the Évora Massif and the Beja Igneous Complex include three successive stages of bimodal magmatism, with a chemical composition indicative of a long-lived subduction process lasting from the Tournaisian to the Moscovian in the OMZ. The earliest stage of arc magmatism includes the Tournaisian Beja and Torrão gabbro-dioritic rocks of the Layered Gabbroic Sequence. We present new geochemical and Nd isotopic and U-Pb geochronological data for magmatic rocks from the Main (Visean-Serpukhovian) and Latest (Bashkirian-Moscovian) stages of arc magmatism. Visean Toca da Moura trachyandesite and rhyolites and Bashkirian Baleizão porphyries and Alcáçovas quartz diorite share enriched, continental-crust like characteristics, as indicated by major and trace elements, mainly suggesting the addition of calc-alkaline magma extracted from various mantle sources in a subduction-related setting (i.e., Paleotethys subduction). New U-Pb zircon geochronology data have allowed us to establish a crystallization age of 317 ± 3 Ma (Bashkirian) for Alcáçovas quartz diorite that confirms a temporal link with Baleizão porphyry. Positive εNd(t) values for the Carboniferous igneous rocks of the Beja Igneous Complex and the Évora gneiss dome indicate production of new juvenile crust, whereas negative εNd(t) values also suggest different grades of magma evolution involving crustal contamination. The production and evolution of Carboniferous continental crust in the OMZ was most likely associated with the development of an active continental margin during the convergence of the Paleotethys Ocean with Gondwana, involving juvenile materials and different grades of crustal contamination.Portuguese Foundation for Science and Technology project UIDB-04683-2020-ICTSpanish Research Agency, grant PGC2018-096534-B-I00 IBERCRUS

A Comparative Analysis of Phytovolume Estimation Methods Based on UAV-Photogrammetry and Multispectral Imagery in a Mediterranean Forest

Management and control operations are crucial for preventing forest fires, especially in Mediterranean forest areas with dry climatic periods. One of them is prescribed fires, in which the biomass fuel present in the controlled plot area must be accurately estimated. The most used methods for estimating biomass are time-consuming and demand too much manpower. Unmanned aerial vehicles (UAVs) carrying multispectral sensors can be used to carry out accurate indirect measurements of terrain and vegetation morphology and their radiometric characteristics. Based on the UAV-photogrammetric project products, four estimators of phytovolume were compared in a Mediterranean forest area, all obtained using the difference between a digital surface model (DSM) and a digital terrain model (DTM). The DSM was derived from a UAV-photogrammetric project based on the structure from a motion algorithm. Four different methods for obtaining a DTM were used based on an unclassified dense point cloud produced through a UAV-photogrammetric project (FFU), an unsupervised classified dense point cloud (FFC), a multispectral vegetation index (FMI), and a cloth simulation filter (FCS). Qualitative and quantitative comparisons determined the ability of the phytovolume estimators for vegetation detection and occupied volume. The results show that there are no significant differences in surface vegetation detection between all the pairwise possible comparisons of the four estimators at a 95% confidence level, but FMI presented the best kappa value (0.678) in an error matrix analysis with reference data obtained from photointerpretation and supervised classification. Concerning the accuracy of phytovolume estimation, only FFU and FFC presented differences higher than two standard deviations in a pairwise comparison, and FMI presented the best RMSE (12.3 m) when the estimators were compared to 768 observed data points grouped in four 500 m2 sample plots. The FMI was the best phytovolume estimator of the four compared for low vegetation height in a Mediterranean forest. The use of FMI based on UAV data provides accurate phytovolume estimations that can be applied on several environment management activities, including wildfire prevention. Multitemporal phytovolume estimations based on FMI could help to model the forest resources evolution in a very realistic way

Rota do Património Industrial do Anticlinal de Estremoz

Os Concelhos de Estremoz, Borba e Vila Viçosa, tradicionalmente e desde tempos imemoriais constituem uma forte influência da indústria extractiva de mármores como rocha ornamental. A evolução geológica da Península Ibérica permitiu que no Alto Alentejo se formasse uma das mais importantes e famosas jazidas marmóreas a nível mundial. O anticlinal de Estremoz, com cerca de 42 km de comprimento e 8 km de largura é de facto um local impressionante onde a força e o engenho do homem se tem feito sentir ao longo de décadas, virando a “terra do avesso”. Os 27 km2 onde o mármore se concentra constituem um local de forte extracção e de grande concentração de pedreiras, com impacto ambiental inevitável, onde a pedra exposta e acumulada em grandes escombreiras “vive paredes meias” com a planície alentejana e extensos olivais. Na impossibilidade de se recuperar ambientalmente este local, quer por questões de ordem económica, quer por questões estratégicas, visto tratar-se de um recurso natural, há que promover o local e reconvertê-lo para o turismo industrial e científico

Modification of microclimate by an isolated ash-tree (Fraxinus angustifolia

Estudaram-se as alterações microclimáticas decorrentes da presença de árvores isoladas de freixo (Fraxinus angustifolia Vahl) num lameiro próximo de Alfaião (41º 46’ 55’’ N; 6º 24’ 51’’ W; 510m de altitude), no distrito de Bragança (Nordeste de Portugal), em que o clima é do tipo Csb de Köppen. O lameiro localiza-se no fundo de um pequeno vale, cujos solos correspondem a Fluvissolos êutricos. Durante três anos mediu-se a radiação solar global incidente em campo aberto e a transmitida através da copa da árvore, a temperatura do ar e do solo sob e fora do coberto e a precipitação incidente sob a copa e em campo aberto. Em todas as estações do ano a presença da árvore alterou significativamente o microclima sob a mesma devido à intercepção de radiação solar (cerca de 25 a 35% no Inverno e de 55 a 65% no Verão) e de cerca de 40% do total anual da precipitação bruta (52-56% no período de Maio- Setembro e 35% no período de ausência de folhagem). As temperaturas médias do ar sob a influência da copa (SIC) da árvore foram superiores às observadas fora da influência da copa (FIC), com as diferenças máximas ocorrendo durante o período nocturno e sendo da ordem de 3ºC no Verão e de 5ºC no Inverno. Os valores médios da temperatura do solo foram superiores na área SIC durante o Inverno (1,1ºC à profundidade de 20 cm) e no Verão na área FIC (1ºC à profundidade de 2 cm). As amplitudes térmicas no ar e no solo da área SIC foram inferiores às observadas na FIC. As condições microclimáticas observadas sob coberto poderão favorecer o desenvolvimento da vegetação herbácea no fim do Inverno, o que pode afectar a produção de biomassa das herbáceas.Changes in microclimate caused by an isolated ash tree (Fraxinus angustifolia Vahl) were assessed in a pasture land close to Bragança (41º 46’ 55’’ N; 6º 24’ 51’’ W; 510m de altitude), in Northeastern Portugal), where climate is Csb according to Köppen. The experimental site was located in the bottom of a small valley, and soils mostly fit the Eutric Fluvisols. Solar radiation, rainfall, and air and soil temperature were measured during three years beneath the tree canopy and in the open. Results showed that the microclimate conditions under the tree canopy were significantly different from those in the open. This is due to solar radiation interception (about 25 a 35% in winter and 55 a 65% in summer) and the interception of about 40% of the gross rainfall (52-56% during May- -October, and 35% when the foliage was absent). Mean air temperatures under the canopy were higher than those in the open, with the differences being greater at nigth, reaching about 3ºC in summer and 5ºC in winter. Compared to the open, mean soil temperatures in winter were higher (about 1ºC at 20 cm depth) beneath the canopy, but were smaller (1ºC at 2 cm depth) in summer. Amplitudes of soil and air temperature were lower under the tree canopy than in the open. These microclimate conditions under the canopy may favour both the herbaceous biomass production and the earlier development of herbaceous at the end of winter

Influência da copa de Fraxinus angustifolia Vahl nas características do gotejo e do escorrimento ao longo do tronco.

O presente estudo teve como objectivo avaliar o efeito da copa de freixo nas características do gotejo e do escorrimento ao longo do tronco. A partir da análise química das soluções recolhidas quantificaram-se os nutrientes provenientes da atmosfera, bem como os transferidos da árvore para o solo através do gotejo e escorrimento ao longo do tronco. A passagem da precipitação através da copa conduziu, em geral, a um aumento dos valores de pH, dos teores de carbono (COD) e azoto (NOD) orgânicos dissolvidos e de nutrientes da solução de gotejo, em relação à precipitação bruta, devido à lavagem e/ou lixiviação dos tecidos vegetais. As concentrações de elementos na solução de escorrimento ao longo do tronco foram bastante superiores às do gotejo e precipitação bruta. Assim, os fluxos anuais em 2001 de COD, NOD, N-NH4+, N-NO3-, Cl, K, Na, Ca, Mg e P na precipitação bruta foram, respectivamente, 3.93, 0.92, 0.20, 0.06, 1.81, 2.40, 1.11, 1.16, 0.29 e 0.06g m-2; os valores referentes ao gotejo foram de 8.65, 1.12, 0.20, 0.03, 3,63, 4.22, 1.43, 1.70, 0.91 e 0.26g m-2. Em relação ao escorrimento ao longo do tronco, os fluxos variarão naturalmente com a área em torno do tronco da árvore, susceptível de ser influenciada por esta solução. As elevadas quantidades de nutrientes restituídas ao solo pelo gotejo e pelo escorrimento ao longo do tronco em relação à precipitação bruta, poderão contribuir para a diferenciação das características do solo sob a copa das árvores

As Rochas Metamórficas e Plutónicas do Rio Almansor: Um Património Geológico a Preservar

No Rio Almansor, que circunda a cidade de Montemor-o-Novo, encontram-se afloramentos de rochas metamórficas formadas há cerca de 340 milhões de anos, a pelo menos 11 km de profundidade e sob elevadas temperaturas (migmatitos e gnaisses) em associação com rochas magmáticas (rochas graníticas). A geodiversidade aqui observada tem um extraordinário interesse científico e educativo que deve ser preservado e estudado para benefício das gerações atuais e futuras. Este trabalho pretende, ao resumir a informação geológica disponível na literatura científica sobre estes sítios geológicos, alertar para a importância de implementar ações de valorização, conservação e divulgação do Património Natural na região do Alentejo