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DOI 10.5194/essd-15-2695-2023
Antarctic Bedmap data: Findable, Accessible, Interoperable, and Reusable (FAIR) sharing of 60 years of ice bed, surface, and thickness data
2023-7-17
Fremand, Alice C.
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Fretwell, Peter
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Bodart, Julien A.
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Pritchard, Hamish D.
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Aitken, Alan
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Bamber, Jonathan L.
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Bell, Robin
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Bianchi, Cesidio
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Bingham, Robert G.
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Blankenship, Donald D.
One of the key components of this research has been the mapping of Antarctic bed topography and ice thickness parameters that are crucial for modelling ice flow and hence for predicting future ice loss and the ensuing sea level rise. Supported by the Scientific Committee on Antarctic Research (SCAR), the Bedmap3 Action Group aims not only to produce new gridded maps of ice thickness and bed topography for the international scientific community, but also to standardize and make available all the geophysical survey data points used in producing the Bedmap gridded products. Here, we document the survey data used in the latest iteration, Bedmap3, incorporating and adding to all of the datasets previously used for Bedmap1 and Bedmap2, including ice bed, surface and thickness point data from all Antarctic geophysical campaigns since the 1950s. More specifically, we describe the processes used to standardize and make these and future surveys and gridded datasets accessible under the Findable, Accessible, Interoperable, and Reusable (FAIR) data principles. With the goals of making the gridding process reproducible and allowing scientists to re-use the data freely for their own analysis, we introduce the new SCAR Bedmap Data Portal (https://bedmap.scar.org, last access: 1 March 2023) created to provide unprecedented open access to these important datasets through a web-map interface. We believe that this data release will be a valuable asset to Antarctic research and will greatly extend the life cycle of the data held within it. Data are available from the UK Polar Data Centre: https://data.bas.ac.uk (last access: 5 May 2023 ). See the Data availability section for the complete list of datasets.
Scopus© Citations 45 4
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DOI 10.1017/jog.2022.91
Prefacing unexplored archives from Central Andean surface-to-bedrock ice cores through a multifaceted investigation of regional firn and ice core glaciochemistry
2023-8
Clifford, Heather M.
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Potocki, Mariusz
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Rodda, Charles
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Dixon, Daniel
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Birkel, Sean
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Handley, Michael
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Korotkikh, Elena
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Introne, Douglas
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Schwanck, Franciele
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Tavares, Flavia A.
Shallow firn cores, in addition to a near-basal ice core, were recovered in 2018 from the Quelccaya ice cap (5470 m a.s.l) in the Cordillera Vilcanota, Peru, and in 2017 from the Nevado Illimani glacier (6350 m a.s.l) in the Cordillera Real, Bolivia. The two sites are similar to 450 km apart. Despite meltwater percolation resulting from warming, particle-based trace element records (e.g. Fe, Mg, K) in the Quelccaya and Illimani shallow cores retain well-preserved signals. The firn core chronologies, established independently by annual layer counting, show a convincing overlap indicating the two records contain comparable signals and therefore capture similar regional scale climatology. Trace element records at a similar to 1-4 cm resolution provide past records of anthropogenic emissions, dust sources, volcanic emissions, evaporite salts and marine-sourced air masses. Using novel ultra-high-resolution (120 mu m) laser technology, we identify annual layer thicknesses ranging from 0.3 to 0.8 cm in a section of 2000-year-old radiocarbon-dated near-basal ice which compared to the previous annual layer estimates suggests that Quelccaya ice cores drilled to bedrock may be older than previously suggested by depth-age models. With the information collected from this study in combination with past studies, we emphasize the importance of collecting new surface-to-bedrock ice cores from at least the Quelccaya ice cap, in particular, due to its projected disappearance as soon as the 2050s.
Scopus© Citations 6 1
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DOI 10.3389/feart.2020.00091
Editorial: Climate Impacts on Glaciers and Biosphere in Fuego-Patagonia
2020-04-09
Schneider, Christoph
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Braun, Matthias Holger
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Schaefer, Marius
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Griessinger, Jussi
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Casassa, Gino
EDITORIAL article Front. Earth Sci., 09 April 2020Sec. Cryospheric Sciences Volume 8 - 2020 | https://doi.org/10.3389/feart.2020.00091
Scopus© Citations 2 2
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DOI 10.1080/15230430.2022.2071793
Glacier inventory and recent variations of Santa Ines Icefield, Southern Patagonia
2022-12-31
Gurdiel, Isaac
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Rada Giacaman, Camilo Andres
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Malz, Philipp
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Braun, Matthias
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Casassa, Gino
The study of glaciers in remote regions improves our understanding of global glacier change. With an area of 149.31 +/- 1.84 km(2), the Santa Ines Icefield constitutes one of the largest and least studied and explored glaciated areas of Southern Patagonia. We study the extent and glacier variations of the Santa Ines Icefield over the last 75 years, and we generate the most detailed glacier inventory to date of its 24 constituting glaciers. We estimate surface elevation changes between 2000 and 2014 using Shuttle Radar Topography Mission (SRTM) and TanDEM-X digital elevation models. Our results show a generalized trend of retreat, with a glacier area loss of -9.78 +/- 1.52 km(2) between 1998 and 2020, with annual rate increase from -0.15 +/- 0.01 km(2) a(-1) (1998-2005) to -0.58 +/- 0.10 km(2) a(-1) (2005-2020), and an average thinning of 0.60 +/- 0.26 m a(-1) (2 sigma) between 2000 and 2014. No clear correlation was found between retreat or thinning rates and Accumulation Area Ratio (AAR), terminus slope, aspect, or glacier type. While ERA5 reanalysis data shows no significant climatic trends in temperature or precipitation, a small warming trend below our detection record is the most likely cause of the observed retreat and thinning of the Santa Ines Icefield.
Scopus© Citations 4 2
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DOI 10.1016/j.atmosenv.2022.119002
Trace metal emission history captured in a Chilean ice core
2022-5-1
Potocki, Mariusz
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Dixon, Daniel A.
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V. Kurbatov, Andrei
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Casassa, Gino
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Zamora, Rodrigo
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Handley, Michael J.
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Introne, Douglas
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Grigholm, Bjorn
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V. Korotkikh, Elena
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Birkel, Sean D.
Ice core records provide a robust tool for reconstructing past climate variability and for improving our under-standing of the relative contributions of natural and anthropogenic emissions into the atmosphere. In particular, heavy metal pollution from anthropogenic emissions poses a significant health and environmental risk. We present a sub-annually dated, continuously sampled Tupungatito ice core (TPG-12) data set that documents change in atmospheric pollution in Central Chile. Results from our well-preserved environmental record display a significant change in atmospheric pollutant concentrations coincident with anthropogenic activities in this re-gion, notably from Chile. TPG-12 Enrichment factors (EFs) for Cd, As, Pb, Cu, and Ag exhibit values in excess of natural inputs over the last one hundred years, with increases beginning around 1930. Terrestrial source dust elements such as Ce, La, Pr, and Ti do not exhibit similarly increased EF values, demonstrating an anthropogenic source for Cd, As, Pb, Cu, and Ag. Our results also capture a decrease in As and Pb starting in the early 2000s, in concert with new environmental regulations in Chile (Caldentey and Mondschein, 2003).
Scopus© Citations 15 2
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DOI 10.3390/rs11030260
Geodetic Mass Balances and Area Changes of Echaurren Norte Glacier (Central Andes, Chile) between 1955 and 2015
2019-02-01
Farias-Barahona, David
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Vivero, Sebastian
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Casassa, Gino
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Schaefer, Marius
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Burger, Flavia
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Seehaus, Thorsten
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Iribarren-Anacona, Pablo
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Escobar, Fernando
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Braun, Matthias H.
The Echaurren Norte Glacier is a reference glacier for the World Glacier Monitoring Service (WGMS) network and has the longest time series of glacier mass balance data in the Southern Hemisphere. The data has been obtained by the direct glaciological method since 1975. In this study, we calculated glacier area changes using satellite images and historical aerial photographs, as well as geodetic mass balances for different periods between 1955 and 2015 for the Echaurren Norte Glacier in the Central Andes of Chile. Over this period, this glacier lost 65% of its original area and disaggregated into two ice bodies in the late 1990s. The geodetic mass balances were calculated by differencing digital elevation models derived from several sources. The results indicated a mean cumulative glacier wide mass loss of -40.64 +/- 5.19 m w.e. (-0.68 +/- 0.09 m w.e. a(-1)). Within this overall downwasting trend, a positive mass balance of 0.54 +/- 0.40 m w.e. a(-1) was detected for the period 2000-2009. These estimates agree with the results obtained with the glaciological method during the same time span. Highly negative mass change rates were found from 2010 onwards, with -1.20 +/- 0.09 m w.e. a(-1) during an unprecedented drought in Central Andes of Chile. The observed area and the elevation changes indicate that the Echaurren Norte Glacier may disappear in the coming years if negative mass balance rates prevail.
Scopus© Citations 45 3
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DOI 10.1088/1748-9326/ac5df0
Black carbon in the Southern Andean snowpack
2022-4-1
Cordero, Raul R.
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Sepulveda, Edgardo
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Feron, Sarah
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Wang, Chenghao
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Damiani, Alessandro
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Fernandoy, Francisco
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Neshyba, Steven
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Rowe, Penny M.
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Asencio, Valentina
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Carrasco Cerda, Jorge Fernando
The Andean snowpack is an important source of water for many communities. As other snow-covered regions around the world, the Andes are sensitive to black carbon (BC) deposition from fossil fuel and biomass combustion. BC darkens the snow surface, reduces the albedo, and accelerates melting. Here, we report on measurements of the BC content conducted by using the meltwater filtration (MF) technique in snow samples collected across a transect of more than 2500 km from the mid-latitude Andes to the southern tip of South America. Addressing some of the key knowledge gaps regarding the effects of the BC deposition on the Andean snow, we identified BC-impacted areas, assessed the BC-related albedo reduction, and estimated the resulting snow losses. We found that BC concentrations in our samples generally ranged from 2 to 15 ng g(-1), except for the nearly BC-free Patagonian Icefields and for the BC-impacted sites nearby Santiago (a metropolis of 6 million inhabitants). We estimate that the seasonal snowpack shrinking attributable to the BC deposition ranges from 4 mm water equivalent (w.e.) at relatively clean sites in Patagonia to 241 mm w.e. at heavily impacted sites close to Santiago.
1Scopus© Citations 17
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DOI 10.1038/s41467-022-28560-w
Black carbon footprint of human presence in Antarctica
2022-2-22
Cordero, Raul R.
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Sepulveda, Edgardo
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Feron, Sarah
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Damiani, Alessandro
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Fernandoy, Francisco
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Neshyba, Steven
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Rowe, Penny M.
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Asencio, Valentina
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Carrasco Cerda, Jorge Fernando
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Alfonso, Juan A.
The snow surrounding research facilities and shore tourist-landing sites in Antarctica was found to be darker than elsewhere in the continent, which suggests that local emissions of black carbon are accelerating seasonal snowmelt in impacted regions. Black carbon (BC) from fossil fuel and biomass combustion darkens the snow and makes it melt sooner. The BC footprint of research activities and tourism in Antarctica has likely increased as human presence in the continent has surged in recent decades. Here, we report on measurements of the BC concentration in snow samples from 28 sites across a transect of about 2,000 km from the northern tip of Antarctica (62 degrees S) to the southern Ellsworth Mountains (79 degrees S). Our surveys show that BC content in snow surrounding research facilities and popular shore tourist-landing sites is considerably above background levels measured elsewhere in the continent. The resulting radiative forcing is accelerating snow melting and shrinking the snowpack on BC-impacted areas on the Antarctic Peninsula and associated archipelagos by up to 23 mm water equivalent (w.e.) every summer.
Scopus© Citations 73 1
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DOI 10.25268/bimc.invemar.2021.50.suplesp.949
Study of the Lange Glacier and its impact due to temperature increase in Admiralty Bay, King George Island, Antarctica
2021-12
Mojica-Moncada, Diego F.
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Cardenas Mansilla, Carlos Alberto
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Mojica-Moncada, Jhon F.
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Brondi, Fabian
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Barragán-Barrera, Dalia C.
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Marangunic, Cedomir
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Holland, David
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Franco Herrera, Andrés
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Casassa, Gino
ABSTRACT In the western Antarctic Peninsula one of the areas the highest warming in the southern hemisphere has been identified. To characterize this tendency, we selected the Lange Glacier (LG) on King George Island, to evaluate: 1) LG surface temperature and dynamics using stakes with temperature data loggers; 2) LG submerged thickness and sea parameters through bathymetry (BT) and 29 CTD stations in front of LG; 3) glacier front (GF) using BT and a Digital Elevation Model (DEM); 4) change in GF position using DEM and historical data of GF width; 5) Calving flux (QC). Our findings showed 85 % of temperatures were above the 0 °C melting point (mean = 5.0 ± 5.2 °C). The stakes had an average ice loss of 9.3 ± 1.3 cm. The LG mean dynamics was 8.8 ± 1.5 m (0.40 ± 0.70 m/day), corroborated by Sentinel-1 satellite images (Offset Tracking = 0.43 ± 0.01 m/day). An intrusion of external waters warmer in the LG bay was identified, which destabilizes the water column due to convection processes. Our findings together indicated a continuous glacial melt that increases its dynamics due to the increase in temperature, with a contribution of fresh water to the Admiralty Bay. Based on historical results and this study, the LG retracement was estimated in 2,492 m between 1956 and 2019.
Scopus© Citations 4 2
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DOI 10.22456/1807-9806.109984
Ionic content in a firn core from the antarctic plateau Conteúdo iônico em um testemunho de firn do platô antártico
2020
Gerhard, Nicoli P.
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Simões, Jefferson C.
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Thoen, Isaías U.
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Tavares, Flávia A.
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Casassa, Gino
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Bernardo, Ronaldo T.
This work investigates the ionic content of the upper 28.73 m of the BR-IC-2 core (88°01'21.3"S; 82°04'21.7"W) collected during the Chilean-Brazilian Antarctic traverser in the austral summer of 2004/05. The concentrations of the major ions Na+, K+, Mg2+, Ca2+, Cl-, NO3-and SO4 2-and organic acid H3 CSO3-(methanesulfonate-MS-) were determined by Ion chromatography. Dating, based on the correlation between Na+ and nssSO4 2-(non sea salt sulfate) concentrations, the δD isotopic ratio and the identification of volcanic eruption layers (Pinatubo / Cerro Hudson in 1993, Agung in 1965 and possibly Bristol Island in 1936) found an age of 85 years (1918–2003) for the core, with precision of ± 3 years. From this dating, it was possible to establish the mean annual precipitation at this site: 0.15 m eq H2 O. A low contribution of sea salts aerosols and a large crustal and biogenic contribution were found, indicated by the concentrations of nssCa2+ and nssSO4 2-, respectively. The high value of the Cl- / Na+ ratio (4.96) indicates that factors other than the contribution of sea salt contribute to the concentrations of these ions, such as the input or formation of HCl and the lower depletion of Cl-. The K+ and Mg2+ concentrations, although poorly correlated with other ions, are of marine origin. MS- shows low values for the region and NO3-has no correlation with other ions, due to complex sources since this ion appears as a secondary aerosol.
Scopus© Citations 1 11

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