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The vanishing snow cover in Serra da Estrela:
Mora, Carla; Vieira, GonçaloThis study investigates the evolution of snow cover in Serra da Estrela, the highest mountain in mainland Portugal, by integrating observational data from the Penhas Douradas meteorological station, remote sensing imagery, and climate model outputs. Results reveal a marked decline in the number of snow cover days at Penhas Douradas, dropping from an average of 53 days in the 1950s to 28 days in the 2010s, corre...
Trace elements in soils of the Antarctic ice-free areas: Insights on natural ge...
Zilhão, Henrique; Cesário, Rute; Vieira, Gonçalo; Canário, JoãoClimate change is transforming the ice-free areas of Antarctica, leading to rapid changes in terrestrial ecosystems. These areas represent <0.5% of the continent and coincide with the most anthropogenically pressured sites, where the human footprint is a source of contamination. Simultaneously, these are the locations where permafrost can be found, not being clear what might be the consequences following its de...
Natural organic matter dynamics in permafrost peatlands: critical overview of r...
Folhas, Diogo; Couture, Raoul-Marie; Laurion, Isabelle; Vieira, Gonçalo; Canário, JoãoRising temperatures are destabilizing permafrost in northern latitudes, leading to the mobilization, transformation and cycling of natural organic matter (NOM), nutrients, and contaminants into newly formed aquatic systems. Analyzing the chemical composition of organic matter is crucial for understanding the biogeochemical processes at play. Furthermore, it is essential to investigate how seasonal variations an...
Recent advances in the study of mercury biogeochemistry in Arctic permafrost ec...
Malcata Martins, Beatriz; Hintelmann, Holger; Pilote, Martin; Vieira, Gonçalo; Canário, JoãoPermafrost predominates in polar and high mountain regions, encompassing nearly 15 % of the exposed land in the Northern Hemisphere. It denotes soil or rock that remains at or below 0 °C for the duration of at least two consecutive years. These frozen soils serve as a barrier to contaminants that are stored and accumulated in permafrost over extended periods of time. One of these chemical compounds is mercury (...
A multi-embankment Chalcolithic walled enclosure
Texugo, André; Basílio, Ana Catarina; Pina, Pedro; Goyanes, Gabriel; Vieira, Gonçalo- Ota, a key part of the Chalcolithic walled enclosure phenomenon in Portuguese Estremadura, represents a unique settlement strategy within the actual territory of Portugal. The architecture and social dynamics of this site remained largely unexplored until 2019. This study marks a significant shift in its study, utilizing a synergistic approach of archaeology and geotechnologies, embodied in the using an Unman...
Ground surface temperature regimes are controlled by the topography and snow co...
Baptista, Joana; Vieira, Gonçalo; Lee, HyoungseokGround Surface Temperature (GST) is especially relevant in permafrost regions, such as the ice-free areas of the Antarctic Peninsula, to the understanding of environmental changes, where a long-term warming trend has been detected since 1950. To better understand GST regimes and the topoclimatic controlling factors, 20 iButtons were installed at sites according to elevation, exposure, curvature, and proximity t...
Diversity of lakes and ponds in the forest-tundra ecozone: from limnicity to li...
Freitas, Pedro; Vieira, Gonçalo; Martins, Diana; Canário, João; Pina, Pedro; Heim, Birgit; Juhls, Bennet; Couture, Raoul-Marie; Vincent, Warwick F.Arctic and subarctic landscapes have unique hydrological and limnological features and are now experiencing rapid change due to climate warming and permafrost thaw. The highly abundant lakes, ponds, and rivers across these landscapes play an increasingly important role in global biogeochemical cycles and are sentinels of environmental changes. However, studying these remote waters poses challenges for both in s...
Microscale is key to model current and future Maritime Antarctic vegetation
Matos, Paula; Rocha, Bernardo; Pinho, Pedro; Miranda, Vasco; Pina, Pedro; Goyanes, Gabriel; Vieira, GonçaloDespite being one of the most pristine regions in the world, Antarctica is currently also one of the most vulnerable to climate change. Antarctic vegetation comprises mostly lichens and bryophytes, complemented in some milder regions of Maritime Antarctica by two vascular plant species. Shifts in the spatial patterns of these three main vegetation groups have already been observed in response to climate change,...
Multi-millennia surface dynamics: novel investigation approach unveils climate ...
Raab, Gerald; Vieira, Gonçalo; Migoń, Piotr; Tikhomirov, Dmitry; Christl, Marcus; Egli, Markus; Scarciglia, FabioMulti-millennia data logs on surface denudation variation in alpine landscapes are scarce, yet they are needed to understand the impacts of environmental changes on denudation. On the example of the Serra da Estrela plateau in Portugal, we explored a new archive, vertical bedrock outcrops (tors), and the capability of the Tor Exhumation/Exposure Approach (TEA) to capture surface denudation variations even in fo...
Employing automated electrical resistivity tomography for detecting short- and ...
Farzamian, Mohammad; Herring, Teddi; Vieira, Gonçalo; de Pablo, Miguel Angel; Yaghoobi Tabar, Borhan; Hauck, ChristianRepeated electrical resistivity tomography (ERT) surveys can substantially advance the understanding of spatial and temporal freeze–thaw dynamics in remote regions, such as Antarctica, where the evolution of permafrost has been poorly investigated. To enable time-lapse ERT surveys in Antarctica, an automated ERT (A-ERT) system is required, as regular site visits are not feasible. In this context, we developed a...