Establishing the trajectory of thinning of the West Antarctic ice sheet (WAIS) since the last glacial maximum (LGM) is important for addressing questions concerning ice sheet (in)stability and changes in global sea level. Here we present detailed geomorphological and cosmogenic nuclide data from the southern Ellsworth Mountains in the heart of the Weddell Sea embayment that suggest the ice sheet, nourished by increased snowfall until the early Holocene, was close to its LGM thickness at 10 ka. A pulse of rapid thinning caused the ice elevation to fall ∼400 m to the present level at 6.5-3.5 ka, and could have contributed 1.4-2 m to global sea-level rise. These results imply that the Weddell Sea sector of the WAIS contributed little to late-glacial pulses in sea-level rise but was involved in mid-Holocene rises. The stepped decline is argued to reflect marine downdraw triggered by grounding line retreat into Hercules Inlet.
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http://dx.doi.org/10.1038/ncomms12511 | DOI Listing |
Discharge of calved ice, runoff and mixing driven by subglacial discharge plumes likely have consequences for marine biogeochemistry in Disko Bay, which hosts the largest glacier in the northern hemisphere, Sermeq Kujalleq. Glacier retreat and increasing runoff may impact the marine silica cycle because glaciers deliver elevated concentrations of dissolved silica (dSi) compared to other macronutrients. However, the annual flux of dSi delivered to the ocean from the Greenland Ice Sheet is poorly constrained because of difficulties distinguishing the overlapping influence of different dSi sources.
View Article and Find Full Text PDFHeliyon
December 2024
Groupe de Recherche en Écologie de la MRC Abitibi (GREMA), Institut de Recherche sur les Forêts, Université du Québec en Abitibi-Témiscamingue, 341 Rue Principale N, Amos, QC, J9T 2L8, Canada.
Lake cyanobacteria can overgrow and form blooms, often releasing life-threatening toxins. Harmful algal blooms (HABs) are typically caused by excess nutrients and high temperatures, but recent observations of cyanobacteria beneath the ice in boreal lakes suggest that the dynamics are more complex. This study investigates the seasonal dynamics of HABs in boreal lakes and identifies their driving factors.
View Article and Find Full Text PDFCryobiology
January 2025
Specialized Surgical Hospital "Doctor Malinov", 46, Gotse Delchev blvd., 1860 Sofia, Bulgaria.
The cryopreservation of human spermatozoa is an integral part of cryobiology, aiming to support the in-vitro fertilization. The latter relies on the availability of as much as possible reproductively active spermatozoa, whose number after thawing decreases due to the accompanied freezing injury and the cytotoxicity of cryoprotectants. An innovative option to circumvent these obstacles is to make the freezing interface non-wettable, by coating it with rapeseed oil soot possessing intrinsic cryoprotective properties, delaying the ice formation and possibly providing identical rates of intracellular dehydration and extracellular crystallization.
View Article and Find Full Text PDFEnviron Monit Assess
January 2025
College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing, China.
Exploring the response relationship between civil war, population and land cover change is of great practical significance for social stability in Myanmar. However, the ongoing civil war in Myanmar hinders direct understanding of the situation on the ground, which in turn limits detailed study of the intricate relationship between the dynamics of the civil war and its impact on population and land. Therefore, this paper explores the response relationship between civil war conflict and population and land cover change in Myanmar from 2010 to 2020 from the perspective of remote sensing using the land cover data we produced, the open spatial demographics data, and the armed conflict location and event data project.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Geography, Centre for Northern Studies (CEN), & Takuvik International Research Laboratory, Université Laval, Québec, QC, Canada.
The Arctic is among the most rapidly warming regions on Earth, and climate change has triggered widespread alterations to its cryosphere and ecosystems. Among these, high Arctic lakes are highly sensitive to rising temperatures due to the influence of ice cover on multiple limnological processes. Here, we studied the sediments of three lakes on northern Ellesmere Island (82.
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