[{"awards": "2149518 Fudge, Tyler; 2019719 Brook, Edward", "bounds_geometry": ["POINT(159.356 -76.73)"], "date_created": "Fri, 19 Dec 2025 00:00:00 GMT", "description": "These data cover four depth regimes from the ALHIC1901 core from the Allan Hills Blue Ice Area, Antarctica. We derived crystal properties such as grain size and preferred orientation of the c-axis (fabric) via an Automated Fabric Analyser (G50 by Russelhead Instruments). These data are useful for understanding the current deformation at the ALHIC1901 site impacting the preserved climate record.", "east": 159.356, "geometry": ["POINT(159.356 -76.73)"], "keywords": "Air Bubbles; Allan Hills; Antarctica; Bubble Number Density; Cryosphere; Ice Deformation; Microstructure; Porosity", "locations": "Antarctica; Allan Hills", "north": -76.73, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Stoll, Nicolas", "project_titles": "Center for Oldest Ice Exploration; Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections", "projects": [{"proj_uid": "p0010321", "repository": "USAP-DC", "title": "Center for Oldest Ice Exploration"}, {"proj_uid": "p0010365", "repository": "USAP-DC", "title": "Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "COLDEX", "south": -76.73, "title": "Allan Hills ALHIC1901 ice core fabric data", "uid": "602011", "west": 159.356}, {"awards": "2019719 Brook, Edward; 2149518 Fudge, Tyler", "bounds_geometry": ["POINT(159.356 -76.73)"], "date_created": "Fri, 19 Dec 2025 00:00:00 GMT", "description": "These data cover four depth regimes from the ALHIC1901 core from the Allan Hills Blue Ice Area, Antarctica. We derived several 2D bubble characteristics from analysing stinted images of ice sample thin sections, such as bubble size and elongation (aspect ratio) These data are useful for understanding the current deformation at the ALHIC1901 site impacting the preserved climate record.", "east": 159.356, "geometry": ["POINT(159.356 -76.73)"], "keywords": "Air Bubbles; Allan Hills; Antarctica; Bubble Number Density; Cryosphere; Ice Deformation; Microstructure; Porosity", "locations": "Allan Hills; Antarctica", "north": -76.73, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Stoll, Nicolas; Fudge, T. J.", "project_titles": "Center for Oldest Ice Exploration; Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections", "projects": [{"proj_uid": "p0010321", "repository": "USAP-DC", "title": "Center for Oldest Ice Exploration"}, {"proj_uid": "p0010365", "repository": "USAP-DC", "title": "Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "COLDEX", "south": -76.73, "title": "Allan Hills ALHIC1901 ice core 2D bubble parameters", "uid": "602010", "west": 159.356}, {"awards": "2019719 Brook, Edward; 2149518 Fudge, Tyler", "bounds_geometry": ["POINT(159.356 -76.73)"], "date_created": "Fri, 19 Dec 2025 00:00:00 GMT", "description": "These data cover several depth regimes from the ALHIC1901 core from the Allan Hills Blue Ice Area, Antarctica. We derived several bubble characteristics from 3D Computer Tomography analysis, such as bubble size, elongation (aspect ratio), number density and porosity. These data are useful for understanding the current deformation at the ALHIC1901 site impacting the preserved climate record.", "east": 159.356, "geometry": ["POINT(159.356 -76.73)"], "keywords": "Air Bubbles; Allan Hills; Antarctica; Bubble Number Density; Cryosphere; Ice Deformation; Microstructure; Porosity", "locations": "Antarctica; Allan Hills", "north": -76.73, "nsf_funding_programs": "Antarctic Glaciology; Antarctic Glaciology", "persons": "Stoll, Nicolas; Freitag, Johannes", "project_titles": "Center for Oldest Ice Exploration; Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections", "projects": [{"proj_uid": "p0010321", "repository": "USAP-DC", "title": "Center for Oldest Ice Exploration"}, {"proj_uid": "p0010365", "repository": "USAP-DC", "title": "Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "COLDEX", "south": -76.73, "title": "Allan Hills ALHIC1901 ice core 3D bubble parameters", "uid": "602009", "west": 159.356}, {"awards": null, "bounds_geometry": null, "date_created": "Fri, 12 Dec 2025 00:00:00 GMT", "description": "The spatial variability of firn properties, including microstructure, is critical for mass-balance estimates and ice- core interpretations. This includes local and regional variations in firn microstructure, which influence compaction and air movement in the firn. Some of the oldest ice cores are located in blue-ice areas and originated from low-accumulation areas. Surface processes, including small variations in surface conditions and topography, may cause significant alteration of the firn microstructure and bulk firn properties in low-accumulation areas, as firn may interact with surface processes for long periods of time (e.g., hundreds of years). Here, we examine the impact of very low-accumulation rates (A = O(10\u22123 \u2212 10\u22122 m/a)) on firn microstructure using micro-computed tomography data from a firn core (PICO2303) retrieved in the accumulation zone at Allan Hills Blue Ice Area (BIA), Antarctica during the 2023-2024 NSF-COLDEX field season. First, we analyze microstructural parameters such as total porosity, density, specific surface area, degree of anisotropy, and structure thickness, as well as 2D and 3D reconstructed digital datasets. Subsequently, we compare our observations with a firn core from Dadic et al. (2015) that we refer to here as AHMIF, and located \u223c9 km downslope. In the PICO2303 core, we find 1) faceted grains, 2) wind crusts, 3) vertically oriented networks, and 4) specific surface area of 1.5 m^2/kg greater and density of 205 kg/m^3 lower below the surface compared to those measured in the AHMIF core. We propose that these characteristics are a result of differences in both surface processes (e.g., formation and decay of sastrugi) and subsurface evolution (e.g., depth-hoar formation) that likely occur at varying degrees.", "east": null, "geometry": null, "keywords": "Antarctica; Cryosphere", "locations": "Antarctica", "north": null, "nsf_funding_programs": null, "persons": "Horlings, B. Ilyse", "project_titles": null, "projects": null, "repositories": null, "science_programs": null, "south": null, "title": "Firn microstructure from micro-computer tomography of PICO2303, Allan Hills Blue Ice Area, Antarctica", "uid": "602002", "west": null}, {"awards": "2013987 Zoet, Lucas", "bounds_geometry": null, "date_created": "Wed, 13 Dec 2023 00:00:00 GMT", "description": "This dataset contains AMS results and microstructure analysis from different depths within the sheared till.", "east": null, "geometry": null, "keywords": "Antarctica", "locations": "Antarctica", "north": null, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Zoet, Lucas", "project_titles": "Collaborative Research: Freeze-on of Subglacial Sediments in Experiments and Theory", "projects": [{"proj_uid": "p0010434", "repository": "USAP-DC", "title": "Collaborative Research: Freeze-on of Subglacial Sediments in Experiments and Theory"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": null, "title": "Ring shear bed deformation measurements", "uid": "601757", "west": null}, {"awards": "0944078 Albert, Mary", "bounds_geometry": ["POINT(124.48796 -80.77914)", "POINT(-112.12317 -79.463)"], "date_created": "Wed, 11 Mar 2015 00:00:00 GMT", "description": "This data set contains laboratory measurements of the density and permeability made from firn cores from the lock-in zone through pore close-off at the WAIS Divide and Megadunes sites.", "east": 124.48796, "geometry": ["POINT(124.48796 -80.77914)", "POINT(-112.12317 -79.463)"], "keywords": "Antarctica; Firn; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Ice Core Records; Physical Properties; WAIS Divide; WAIS Divide Ice Core", "locations": "Antarctica; WAIS Divide", "north": -79.463, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Albert, Mary R.", "project_titles": "Firn Metamorphism: Microstructure and Physical Properties", "projects": [{"proj_uid": "p0000049", "repository": "USAP-DC", "title": "Firn Metamorphism: Microstructure and Physical Properties"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "WAIS Divide Ice Core", "south": -80.77914, "title": "Firn Permeability and Density at WAIS Divide", "uid": "609602", "west": -112.12317}, {"awards": "0738975 Baker, Ian", "bounds_geometry": ["POINT(-148.82 -81.66)"], "date_created": "Mon, 26 Nov 2012 00:00:00 GMT", "description": "This data set characterizes the microstructure in ice cores, in particular the microstructural locations of impurities, grain orientations, and strain gradients. The fabric of polycrystalline ice is typically described using only the c-axis orientation, but this is insufficient for a full description of grain orientations in this hexagonal material. Thus, both the a-axis and c-axis are used in this data set showing pole figures for five depths of the Siple Dome (SDMA) core between 640 m and 790 m and misorientation angle distribution for the same grains.", "east": -148.82, "geometry": ["POINT(-148.82 -81.66)"], "keywords": "Antarctica; Glaciers/ice Sheet; Glaciers/Ice Sheet; Glaciology; Sample/collection Description; Sample/Collection Description; Siple Dome; Siple Dome Ice Core; South Pole; WAISCORES", "locations": "Antarctica; South Pole; Siple Dome", "north": -81.66, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Baker, Ian; Obbard, Rachel; Sieg, Katherine", "project_titles": "Advanced Microstructural Characterization of Polar Ice Cores", "projects": [{"proj_uid": "p0000178", "repository": "USAP-DC", "title": "Advanced Microstructural Characterization of Polar Ice Cores"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": "Siple Dome Ice Core", "south": -81.66, "title": "Siple Dome A (SDMA) Grain Orientation 640 - 790 Meters", "uid": "609526", "west": -148.82}, {"awards": "0125276 Albert, Mary", "bounds_geometry": ["POLYGON((124.0218 -80.5304,124.22264 -80.5304,124.42348 -80.5304,124.62432 -80.5304,124.82516 -80.5304,125.026 -80.5304,125.22684 -80.5304,125.42768 -80.5304,125.62852 -80.5304,125.82936 -80.5304,126.0302 -80.5304,126.0302 -80.55538,126.0302 -80.58036,126.0302 -80.60534,126.0302 -80.63032,126.0302 -80.6553,126.0302 -80.68028,126.0302 -80.70526,126.0302 -80.73024,126.0302 -80.75522,126.0302 -80.7802,125.82936 -80.7802,125.62852 -80.7802,125.42768 -80.7802,125.22684 -80.7802,125.026 -80.7802,124.82516 -80.7802,124.62432 -80.7802,124.42348 -80.7802,124.22264 -80.7802,124.0218 -80.7802,124.0218 -80.75522,124.0218 -80.73024,124.0218 -80.70526,124.0218 -80.68028,124.0218 -80.6553,124.0218 -80.63032,124.0218 -80.60534,124.0218 -80.58036,124.0218 -80.55538,124.0218 -80.5304))"], "date_created": "Thu, 01 Nov 2007 00:00:00 GMT", "description": "This data set contains firn physical properties measured in two meter snow pits and from deeper, 12- to 30-meter firn cores. The physical properties measured in the snow pits include density, permeability and microstructure (grain size and pore size). The physical properties measured on firn cores include density, permeability, diffusivity and microstructure. Data are available in Microsoft Excel format and ADOBE PDF and are available via FTP.", "east": 126.0302, "geometry": ["POINT(125.026 -80.6553)"], "keywords": "Antarctica; East Antarctic Plateau; Glaciology; Physical Properties; Snow/ice; Snow/Ice", "locations": "Antarctica; East Antarctic Plateau", "north": -80.5304, "nsf_funding_programs": "Antarctic Glaciology", "persons": "Albert, Mary R.; Courville, Zoe; Cathles, Mac", "project_titles": "Collaborative Research: Characteristics of Snow Megadunes and Their Potential Effect on Ice Core Interpretation", "projects": [{"proj_uid": "p0000587", "repository": "USAP-DC", "title": "Collaborative Research: Characteristics of Snow Megadunes and Their Potential Effect on Ice Core Interpretation"}], "repo": "USAP-DC", "repositories": "USAP-DC", "science_programs": null, "south": -80.7802, "title": "Snow and Firn Permeability: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation", "uid": "609299", "west": 124.0218}]

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Dataset Title/Abstract/Map	NSF Award(s)	Date Created	PIs / Scientists	Project Links	Abstract	Bounds Geometry	Geometry	Selected	Visible
Allan Hills ALHIC1901 ice core fabric data	2149518 2019719	2025-12-19	Stoll, Nicolas	Center for Oldest Ice Exploration Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections	These data cover four depth regimes from the ALHIC1901 core from the Allan Hills Blue Ice Area, Antarctica. We derived crystal properties such as grain size and preferred orientation of the c-axis (fabric) via an Automated Fabric Analyser (G50 by Russelhead Instruments). These data are useful for understanding the current deformation at the ALHIC1901 site impacting the preserved climate record.	["POINT(159.356 -76.73)"]	["POINT(159.356 -76.73)"]	false	false
Allan Hills ALHIC1901 ice core 2D bubble parameters	2019719 2149518	2025-12-19	Stoll, Nicolas; Fudge, T. J.	Center for Oldest Ice Exploration Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections	These data cover four depth regimes from the ALHIC1901 core from the Allan Hills Blue Ice Area, Antarctica. We derived several 2D bubble characteristics from analysing stinted images of ice sample thin sections, such as bubble size and elongation (aspect ratio) These data are useful for understanding the current deformation at the ALHIC1901 site impacting the preserved climate record.	["POINT(159.356 -76.73)"]	["POINT(159.356 -76.73)"]	false	false
Allan Hills ALHIC1901 ice core 3D bubble parameters	2019719 2149518	2025-12-19	Stoll, Nicolas; Freitag, Johannes	Center for Oldest Ice Exploration Collaborative Research: Testing Next Generation Measurement Techniques for Reconstruction of Paleoclimate Archives from Thin or Disturbed Ice Cores Sections	These data cover several depth regimes from the ALHIC1901 core from the Allan Hills Blue Ice Area, Antarctica. We derived several bubble characteristics from 3D Computer Tomography analysis, such as bubble size, elongation (aspect ratio), number density and porosity. These data are useful for understanding the current deformation at the ALHIC1901 site impacting the preserved climate record.	["POINT(159.356 -76.73)"]	["POINT(159.356 -76.73)"]	false	false
Firn microstructure from micro-computer tomography of PICO2303, Allan Hills Blue Ice Area, Antarctica	None	2025-12-12	Horlings, B. Ilyse	No project link provided	The spatial variability of firn properties, including microstructure, is critical for mass-balance estimates and ice- core interpretations. This includes local and regional variations in firn microstructure, which influence compaction and air movement in the firn. Some of the oldest ice cores are located in blue-ice areas and originated from low-accumulation areas. Surface processes, including small variations in surface conditions and topography, may cause significant alteration of the firn microstructure and bulk firn properties in low-accumulation areas, as firn may interact with surface processes for long periods of time (e.g., hundreds of years). Here, we examine the impact of very low-accumulation rates (A = O(10−3 − 10−2 m/a)) on firn microstructure using micro-computed tomography data from a firn core (PICO2303) retrieved in the accumulation zone at Allan Hills Blue Ice Area (BIA), Antarctica during the 2023-2024 NSF-COLDEX field season. First, we analyze microstructural parameters such as total porosity, density, specific surface area, degree of anisotropy, and structure thickness, as well as 2D and 3D reconstructed digital datasets. Subsequently, we compare our observations with a firn core from Dadic et al. (2015) that we refer to here as AHMIF, and located ∼9 km downslope. In the PICO2303 core, we find 1) faceted grains, 2) wind crusts, 3) vertically oriented networks, and 4) specific surface area of 1.5 m^2/kg greater and density of 205 kg/m^3 lower below the surface compared to those measured in the AHMIF core. We propose that these characteristics are a result of differences in both surface processes (e.g., formation and decay of sastrugi) and subsurface evolution (e.g., depth-hoar formation) that likely occur at varying degrees.	[]	[]	false	false
Ring shear bed deformation measurements	2013987	2023-12-13	Zoet, Lucas	Collaborative Research: Freeze-on of Subglacial Sediments in Experiments and Theory	This dataset contains AMS results and microstructure analysis from different depths within the sheared till.	[]	[]	false	false
Firn Permeability and Density at WAIS Divide	0944078	2015-03-11	Albert, Mary R.	Firn Metamorphism: Microstructure and Physical Properties	This data set contains laboratory measurements of the density and permeability made from firn cores from the lock-in zone through pore close-off at the WAIS Divide and Megadunes sites.	["POINT(124.48796 -80.77914)", "POINT(-112.12317 -79.463)"]	["POINT(124.48796 -80.77914)", "POINT(-112.12317 -79.463)"]	false	false
Siple Dome A (SDMA) Grain Orientation 640 - 790 Meters	0738975	2012-11-26	Baker, Ian; Obbard, Rachel; Sieg, Katherine	Advanced Microstructural Characterization of Polar Ice Cores	This data set characterizes the microstructure in ice cores, in particular the microstructural locations of impurities, grain orientations, and strain gradients. The fabric of polycrystalline ice is typically described using only the c-axis orientation, but this is insufficient for a full description of grain orientations in this hexagonal material. Thus, both the a-axis and c-axis are used in this data set showing pole figures for five depths of the Siple Dome (SDMA) core between 640 m and 790 m and misorientation angle distribution for the same grains.	["POINT(-148.82 -81.66)"]	["POINT(-148.82 -81.66)"]	false	false
Snow and Firn Permeability: Characteristics of Snow Megadunes and their Potential Effects on Ice Core Interpretation	0125276	2007-11-01	Albert, Mary R.; Courville, Zoe; Cathles, Mac	Collaborative Research: Characteristics of Snow Megadunes and Their Potential Effect on Ice Core Interpretation	This data set contains firn physical properties measured in two meter snow pits and from deeper, 12- to 30-meter firn cores. The physical properties measured in the snow pits include density, permeability and microstructure (grain size and pore size). The physical properties measured on firn cores include density, permeability, diffusivity and microstructure. Data are available in Microsoft Excel format and ADOBE PDF and are available via FTP.	["POLYGON((124.0218 -80.5304,124.22264 -80.5304,124.42348 -80.5304,124.62432 -80.5304,124.82516 -80.5304,125.026 -80.5304,125.22684 -80.5304,125.42768 -80.5304,125.62852 -80.5304,125.82936 -80.5304,126.0302 -80.5304,126.0302 -80.55538,126.0302 -80.58036,126.0302 -80.60534,126.0302 -80.63032,126.0302 -80.6553,126.0302 -80.68028,126.0302 -80.70526,126.0302 -80.73024,126.0302 -80.75522,126.0302 -80.7802,125.82936 -80.7802,125.62852 -80.7802,125.42768 -80.7802,125.22684 -80.7802,125.026 -80.7802,124.82516 -80.7802,124.62432 -80.7802,124.42348 -80.7802,124.22264 -80.7802,124.0218 -80.7802,124.0218 -80.75522,124.0218 -80.73024,124.0218 -80.70526,124.0218 -80.68028,124.0218 -80.6553,124.0218 -80.63032,124.0218 -80.60534,124.0218 -80.58036,124.0218 -80.55538,124.0218 -80.5304))"]	["POINT(125.026 -80.6553)"]	false	false

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