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- Penultimate Glacial Cycle glacier extent in the Iberian Peninsula: new evidence from the Serra da Estrela (Central System, Portugal)Publication . Vieira, Gonçalo; Palacios, David; Andrés, Nuria; Mora, Carla; Vázquez Selem, Lorenzo; Woronko, Barbara; Soncco, Carmen; Úbeda, Jose; Goyanes, GabrielThe objective of this work is to present a first assessment on the age of the glacial features of the Serra da Estrela, in the central Portugal, Iberian Peninsula (40°19′ N, 7°37′ W, 1993 m), using Cosmic-Ray Exposure dating (in situ cosmogenic 36Cl). A total of 6 samples were dated, 4 extracted from exposed moraine boulders and 2 from glacially polished bedrock surfaces. Despite the low number of samples, the results are consistent, reinforcing previous dating obtained by other methods and geomorphological and paleoclimatic information. The maximum extension of the glaciers occurred at the end of the Penultimate Glacial Cycle (Marine Isotope Stage 6), during Heinrich Stadial 11, around 140 ka. At the end of the Last Glacial Cycle, slightly before the Last Glacial Maximum, at around 30 ka, the Estrela glaciers reached again a similar extent. Finally, the glaciers disappeared fromthe Serra da Estrela at the beginning of the Bølling-Allerød Interstadial, at around 14.2 ka. These data confirm a certain synchronicity in the major glacial phases in most the Mediterranean and also European mountains, although there are notable differences in the maximum extent in the two cycles.
- Evaluation of water resources in a high-mountain basin in Serra da Estrela, central Portugal, using a semi-distributed hydrological modelPublication . Espinha Marques, J.; Samper, J.; Pisani, B.; Alvares, D.; Carvalho, J. M.; Chaminé, H. I.; Marques, J. M.; Vieira, Goncalo; Mora, Carla; Sodré Borges, F.High-mountain basins provide a source of valuable water resources. This paper presents hydrological models for the evaluation of water resources in the highmountain Zeˆzere river basin in Serra da Estrela, Central Portugal. Models are solved with VISUAL BALAN v2.0, a code which performs daily water balances in the root zone, the unsaturated zone and the aquifer and requires a small number of parameters. A lumped hydrological model fails to fit measured stream flows. Its limitations are overcome by considering the dependence of the temperature and precipitation data with elevation and the spatial variability in hydrogeomorphological variables with nine sub-basins of uniform parameters. Model parameters are calibrated by fitting stream flow measurements in the Zeˆzere river. Computed stream flows are highly sensitive to soil thickness, whereas computed groundwater recharge is most sensitive to the interflow and percolation recession coefficients. Interflow is the main component of total runoff, ranging from 41 to 55% of annual precipitation. High interflows are favored by the steep relief of the basin, by the presence of a high permeability soil overlying the fractured low permeability granitic bedrock and by the extensive subhorizontal fracturing at shallow depths. Mean annual groundwater recharge ranges from 11 to 15% of annual precipitation. It has a significant uncertainty due to uncertainties in soil parameters. This methodology proves to be useful to handle the research difficulties regarding a complex mountain basin in a context of data scarcity.
- Landscapes and Landforms of PortugalPublication . Vieira, Gonçalo; Zêzere, José; Mora, CarlaLandscapes and Landforms of Portugal volume presents, for the first time, a series of synthesis chapters on landscape highlights of mainland Portugal, covering a wide diversity of geomorphological settings. These are presented with language and graphic styles that try to bridge-the-gap from professional scientists to undergraduate students, while being also accessible to all those interested in the earth sciences, to help for a better understanding of landscape evolution and specific features of the Portuguese landforms. The authors are physical geographers and geologists, mostly from Portuguese research institutions, all of them having had conducted research in the regions which they present. The main objective of the book is to provide a good overview of the geomorphology of Portugal, but also of its links with human occupation of the territory, geohazards and geoheritage management. This book is a tribute to Prof. António de Brum Ferreira, who has been an inspiration for generations of geomorphologists and students. Landforms and Landscapes of Portugal volume is organized in five thematic parts, i.e. 1. geomorphological setting, dynamics and hazards, 2. coasts, 3. mountains and valleys, 4. urban areas, 5. geoconservation and geoparks. In each part, chapters are ordered geographically from north to south, covering most of mainland Portugal (Fig. 1) [...]
- Aspectos do clima local da ArrábidaPublication . Mora, Carla; Alcoforado, Maria João[…] O trabalho que apresento é um estudo de climatologia local, devendo para isso, teoricamente, a área em análise ter uma extensão entre 100m e 50 km (OKE, 1995). A área em que desenvolvo o presente estudo localiza-se no sul da Península de Setúbal, propriamente na Arrábida e o seu comprimento máximo é de cerca de 27km, enquadrando-se na dimensão referida por OKE. Devido à falta de tempo e de meios para desenvolver trabalho de campo em toda a área, escolhi três áreas de pormenor: a primeira situa-se no Cabo Espichel e tem um comprimento máximo de 4 km; a segunda área situa-se na Bacia de Sesimbra, tendo aproximadamente 3 km de distância; por último, a da Serra da Arrábida, é a mais extensa, com 6 km. […]
- A synthetic map of the climatopes of the Serra da Estrela (Portugal)Publication . Mora, CarlaThe Serra da Estrela is part of the Iberian Central Cordillera and is the highest mountain in mainland Portugal (40◦ 20’N, 7◦ 35’W, 1993 m a.s.l.). The topoclimates are controlled by the NNE-SSW direction of the mountain range, asymmetric exposure to the prevailing westerly air masses, high relief and irregular morphology. Supported by a network of air temperature data loggers, the influence of the topography on the temperature patterns has been examined. A thorough analysis of climate data from meteorological stations, bibliographical references and the study of the terrain characteristics, including field work, remote sensing and GIS-based digital elevation model analyses, allowed the information to be synthesised in a map of the climatopes at the scale 1:75,000. The climatopes are based on the variation of climatic factors as a result of topography and land cover. Each climatope unit responds similarly to the forcing induced by the atmosphere boundary layer and represents a local climate. The map includes 18 types of climatope and contains a simple, easy-to-understand legend for the non-specialist in climatology, with the possibility for application in land planning.