Gonçalo Vieira

University of Lisbon | UL · Institute of Geography and Territorial Planning

Results obtained during the International Polar Year (IPY) on the thermal state of permafrost and the active layer in the Antarctic are presented, forming part of ANTPAS (‘Antarctic Permafrost and Soils’), which was one of the key projects developed by the International Permafrost Association and the Scientific Committee for Antarctic Research for...

The book brings together contributions from over 35 Portuguese geomorphologists, presenting a thorough overview of the main highlights of the landscape of Portugal's mainland, Azores and Madeira. The book, which is a tribute to Professor António de Brum Ferreira, first President of the Portuguese Association of Geomorphologists and former Professor...

Essay: https://arctic.noaa.gov/Report-Card/Report-Card-2020/ArtMID/7975/ArticleID/904/Coastal-Permafrost-Erosion

The 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 po...

As the Arctic warms, permafrost coasts are eroding faster, threatening coastal communities, habitats, and altering sediment and nutrient budgets. The western Canadian Arctic is eroding at a rapid pace, however little is known on changes occurring in the Amundsen Gulf area. This study was conducted in the eastern coast of Parry Peninsula, a neglecte...

Understanding the environmental response to the last glacial termination in regions located in transitional climate zones such as the Atlantic Iberian mountains is crucial to estimate potential changes in regions affected by current glacial melting. We present an 8.5‐m‐long, solid last deglaciation and Holocene chronostratigraphic record including...

Thermokarst lakes and ponds are a common landscape feature resulting from permafrost thaw, but their intense greenhouse gas emissions are still poorly constrained as a feedback mechanism for global warming because of their diversity, abundance, and remoteness. Thermokarst waterbodies may be small and optically diverse, posing specific challenges fo...

Few data are available on how soil erosion rates compare between surfaces of different ages because short-term processes often overprint the longer-term erosion signal. This study investigated the soil dynamics among two end-member sites, a formerly glaciated ('young', maximum glacial extent at 22–30 ka BP) and a non-glaciated ('old') area at the S...

Development of vegetation communities in areas of Antarctica without permanent ice cover emphasizes the need for effective remote sensing techniques for proper monitoring of local environmental changes. Detection and mapping of vegetation by image classification remains limited in the Antarctic environment due to the complexity of its surface cover...

Permafrost coasts are experiencing accelerated erosion in response to above average warming in the Arctic resulting in local, regional, and global consequences. However, Arctic coasts are expansive in scale, constituting 30–34% of Earth’s coastline, and represent a particular challenge for wide-scale, high temporal measurement and monitoring. This...

This paper focuses on the interpretation of the natural components presents at different geosites in the Estrela UNESCO Global Geopark and on the analysis of soil erosion dynamics associated with trampling events in recent years. Three areas were evaluated: Salgadeiras - Covão da Clareza, Lagoa Seca and Covão do Boi. On there, UAV photogrammetry su...

Thermokarst lakes and ponds are a common landscape feature resulting from permafrost thaw, but their intense greenhouse gas emissions are still poorly constrained as a feedback mechanism for global warming because of their diversity, abundance and remoteness. Thermokarst waterbodies may be small and optically diverse, posing specific challenges for...

Remote sensing is a very powerful tool that has been used to identify, map and monitor Antarctic features and processes for nearly one century. Satellite remote sensing plays the main role for about the last five decades, as it is the only way to provide multitemporal views at continental scale. But the emergence of small consumer-grade unoccupied...

Geomorphological mapping in mountain regions is key for a better understanding of past and present environmental dynamics. Here, we present a 1:25000 scale geomorphological map covering 553 km2 of the Aran Valley, Upper Garonne Basin (Central Pyrenees). The map identifies 44 different geomorphological units classified under glacial, periglacial, ni...

Till macrofabric and grain-size analysis of glacial diamictons and landforms present in several valleys of the Serra da Estrela Mountains in central Portugal were used to interpret till types and to reconstruct the glacial paleoprocess history of this mountainous region. Supraglacial melt-out and flow tills are dominant in this range. Supraglacial...

The Serra da Estrela is the highest mountain in mainland Portugal and the western-most glaciated range in the Iberian Central System. The rich features of the glacial geomorphology of the Estrela associated to a climatically sensitive plateau ice-field located between c. 1500 and 2000 m that drained into a set of radial valley glaciers are key asse...

The Upper Garonne Basin included the longest glacier in the Pyrenees during the Late Pleistocene. During major glacial advances, the Garonne palaeoglacier flowed northwards along ~ 80 km from peaks of the axial Pyrenees exceeding 2800–3000 m until the foreland of this mountain range at the Loures–Barousse–Barbazan basin (LBBb), at 420–440 m. Here,...

The Upper Garonne Basin included the largest glacial system in the Pyrenees during the last glacial cycle. Within the long‐term glacial retreat during Termination‐1 (T‐1), glacier fluctuations left geomorphic evidence in the area. However, the chronology of T‐1 glacial oscillations on the northern slopes of the Central Pyrenees is still poorly cons...

The Upper Garonne Basin included the longest glacier in the Pyrenees during the Late Pleistocene. During major glacial advances, the Garonne palaeoglacier flowed northwards along ~ 90 km from peaks of the axial Pyrenees exceeding 2,800-3,000 m until the foreland of this mountain range at the Loures-Barouse-Barbazan basin, at only 420–440 m. Here, t...

Fogo in the Cabo Verde archipelago off western Africa is one of the most prominent and active ocean island volcanoes on Earth, posing an important hazard both to local populations and at a regional level. The last eruption took place between 23 November 2014 and 8 February 2015 in the Chã das Caldeiras area at an elevation close to 1800 ma.s.l. The...

The last overview of the thermal state in the Western Antarctic Peninsula shows that permafrost is close to 0oC in the region. This fact reinforces the importance to study the evolution of permafrost and active layer in the region. However, monitoring of the active layer and permafrost dynamics in Antarctica is generally conducted using only 1-dime...

Warming of the circumpolar north is accelerating permafrost thaw, with implications for landscapes, hydrology, ecosystems and the global carbon cycle. In subarctic Canada, abrupt permafrost thaw is creating widespread thermokarst lakes. Little attention has been given to small waterbodies with area less than 10,000 m 2 , yet these are biogeochemica...

In Europe, a high soil erosion risk is modelled for the Mediterranean area such as the Iberian Peninsula (e.g., EEA, 2009), while actual field data often lacks behind. Here we present the first 239+240Pu soil erosion results (last ~60 years) in the UNESCO Geopark Estrela, Portugal. We investigated soils in a former vastly glaciated and a non-glacia...

Few data are available on how soil erosion rates compare between surfaces of different ages because short-term processes often overprint the longer-term erosion signal. This study investigated the soil dynamics among two end-member sites, a formerly glaciated ('young', maximum glacial extent at 22–30 ka BP) and a non-glaciated ('old') area at the S...

The Antarctic Peninsula (AP) region has been one of the regions on Earth with strongest warming since 1950. However, the northwest of the AP showed a cooling from 2000 to 2015, which had local consequences with an increase in snow accumulation and a deceleration in the loss of mass from glaciers. In this paper, we studied the effects of increased s...

Expansion of Antarctic vegetation in ice-free areas underlines the need for effective remote sensing techniques to properly monitor the changes. Detection and mapping of vegetation remains limited in the Antarctic environment given the complexity of its surface coverage. Some cryptogamic species exhibit low reflectance in the near-infrared region a...

Fogo in the Cape Verde archipelago off Western Africa is one of the most prominent and active ocean island volcanoes on Earth, posing an important hazard to both local populations and at a regional level. The last eruption took place between 23 November 2014 and 8 February 2015 in the Chã das Caldeiras area at an elevation close to 1,800 m above se...

Thermokarst lakes result from the thawing of ice-rich permafrost and are widespread across northern landscapes. These waters are strong emitters of methane, especially in permafrost peatland regions, where they are stained black by high concentrations of dissolved organic matter (DOM). In the present study, we aimed to structurally characterize the...

The applicability of optical satellite data to quantify coastal erosion across the Arctic is limited due to frequent cloud cover. Synthetic Aperture Radar (SAR) may provide an alternative. The interpretation of SAR data for coastal erosion monitoring in Arctic regions is, however, challenging due to issues of viewing geometry, ambiguities in scatte...

Slope failures are widespread phenomena in mid-latitude mountain environments that were glaciated during the Last Glacial Cycle. This is the case of the Aran valley, in the Upper Garonne catchment, Central Pyrenees, that included glaciers several hundred meters thick. Following postglacial warming and ice thinning, the recently deglaciated slopes w...

The Estrela Geopark rises to 1993 m asl and occupies an area over 2000 km² in the western sector of the Iberian Central System, the mountain range that extends from Guadarrama in Spain to Montejunto in the north-west of Lisbon. The Estrela is located in the Central Iberian Zone showing various types of granites and the turbiditic metasediments of t...

Portugal shows a Mediterranean climate with, predominantly, a wet cool season and a dry summer. Despite the concentration of the precipitation in winter, there is a high inter-annual variability, resulting from the latitudinal position in the south-western façade of Europe. The prevailing weather conditions are anticyclonic, with Portugal’s seasona...

The Serra da Estrela is a granite-dominated plateau mountain located in Central Portugal, reaching an elevation of 1993 m. Its position in the western part of the Iberian Central System, elongated morphology in an SW–NE direction, generates an important barrier to the moist Atlantic air masses when they move into Iberia’s interior. This orographic...

The paper focuses on analysis of macro‐ and micromorphological characteristics of relict slope deposits in Serra da Estrela (Portugal) to understand the significance of different slope processes and paleoenvironmental settings. Micromorphology is a useful sedimentology technique allowing significant advances compared to macroscopic techniques. Resu...

Climate-induced warming of permafrost soils is a global phenomenon, with regional and site-specific variations which are not fully understood. In this context, a 2-D automated electrical resistivity tomography (A-ERT) system was installed for the first time in Antarctica at Deception Island, associated to the existing Crater Lake site of the Circum...

Mapping accurately vegetation surfaces in space and time in the ice-free areas of Antarctica can provide important information to quantitatively describe the evolution of their ecosystems. Spaceborne remote sensing is the adequate way to map and evaluate multitemporal changes on the Antarctic vegetation at large but its nature of occurrence, in rel...

Permafrost is present within almost all of the Antarctic's ice-free areas, but little is known about spatial variations in permafrost temperatures except for a few areas with established ground temperature measurements. We modelled a temperature at the top of the permafrost (TTOP) for all the ice-free areas of the Antarctic mainland and Antarctic i...

Since 2006, our research team has been establishing in the islands of Livingston and Deception, (South Shetland archipelago, Antarctica) several monitoring stations of the active layer thickness within the international network Circumpolar Active Layer Monitoring (CALM), and the ground thermal regime for the Ground Terrestrial Network-Permafrost (G...

Barton Peninsula is an ice-free area located in the southwest corner of King George Island (South Shetland Islands, Antarctica). Following the Last Glacial Maximum, several geomorphological features developed in newly exposed ice-free terrain and their distribution provide insights about past environmental evolution of the area. Three moraine syste...

Permafrost is present under almost all of the Antarctic’s ice-free areas but little is known about spatial variations of permafrost temperatures outside a few areas with established ground temperature measurements. We modelled a temperature at the top of the permafrost (TTOP) for all the ice-free areas of Antarctic mainland and Antarctic Islands at...

Climate induced warming of permafrost soils is a global phenomenon, with regional and site-specific variations, which are not fully understood. In this context, a 2D automated electrical resistivity tomography (A-ERT) system was installed for the first time in Antarctica at Deception Island, associated to the existing Crater Lake site of the Circum...

Apresentam-se os resultados da análise de dados de temperatura da rocha medida a 2, 5, 10 e 17 cm de profundidade, nas vertentes norte e sul do Cântaro Gordo, entre dezembro de 1999 e março de 2001. As temperaturas observadas refletem principalmente a influência da insolação e da radiação solar direta. As temperaturas médias são quase sempre mais b...

Thermokarst waterbodies caused by permafrost thawing and degradation are ubiquitous in many subarctic and Arctic regions. They are globally important components of the biogeochemical carbon cycle and have potential feedback effects on climate. These northern waters are mostly small lakes and ponds, and although they may be mapped using very high-re...

ISBN 978-972-636-277-7

The dataset includes rock temperature data from the south and north slopes of the Cântaro Gordo, a granitic ridge rising to 1,875 m asl at the Serra da Estrela, Central-North Portugal ( 40°20'9"N, 7°35'52.75"W). The temperatures were measured at 1, 5, 10 and 17 cm depth at 2-hour intervals, from december 1999 to april 2001. The loggers were install...

The dataset includes rock temperature data from the south and north slopes of the Cântaro Gordo, a granitic ridge rising to 1,875 m asl at the Serra da Estrela, Central-North Portugal ( 40°20'9"N, 7°35'52.75"W). The temperatures were measured at 1, 5, 10 and 17 cm depth at 2-hour intervals, from december 1999 to april 2001. The loggers were install...

Permafrost warming has the potential to amplify global climate change, because when frozen sediments thaw it unlocks soil organic carbon. Yet to date, no globally consistent assessment of permafrost temperature change has been compiled. Here we use a global data set of permafrost temperature time series from the Global Terrestrial Network for Perma...

The dataset includes hourly air temperature and relative humidity data from from Sidi Chamharouch (31.09763ºN, 7.91291º W) at 2370 m a.s.l. and Neltner hut (31.063 ºN, 7.93814 W) at 3210 m a.s.l. in the Oued Ihghyghaye valley (High Atlas, Morocco) from 16 June 2015 to 16 July 2016. The data was collected using a Hobo ProV2 datalogger installed insi...

The Western Antarctic Peninsula (WAP) has shown complex reactions to climate change in the last decades. To evaluate the changes occurring in these environments, permafrost and active layer monitoring and modelling are essential. In this dissertation, the characteristics of the ground temperature regime are analysed and the spatial distribution of...

O Geopark Estrela, com um território de 2216km 2 e dividido administrativamente em 9 municípios, apresenta enormes desafios associados à sua gestão. O facto de quase 50% da área estar classificada como protegida, constitui uma oportunidade, mas também coloca questões, relacionadas com a ocupação do espaço e com a sua conservação, distintas do resta...

Low-land permafrost areas are subject to intense freeze-thaw cycles and characterized by remarkable surface displacement. We used Sentinel-1 SAR interferometry (InSAR) in order to analyse the summer surface displacement over four spots in the Arctic and Antarctica since 2015. Choosing floodplain or outcrop areas as the reference for the InSAR relat...

The personal, commercial, and scientific use of unmanned aerial systems (UAS) in Antarctica has increased dramatically in recent years. Due to the potential benefits for, and negative impacts to, sensitive Antarctic wildlife, the use of UAS (also called unmanned aerial vehicles (UAV), remotely piloted aircraft systems (RPAS) or drones) is a widely...

We installed an automatic Electrical Resistivity Tomography (ERT) and temperature monitoring system under the Circumpolar Active Layer Monitoring (CALM) program in order to study the active layer in the Crater Lake site at Deception Island during 2010. The Western Antarctic Peninsula region is one of the hot spots of climate change and one of the m...