Chronostratigraphy of the Larsen blue-ice area in northern Victoria Land, East Antarctica, and its implications for paleoclimate

In blue-ice areas (BIAs), deep ice is directly exposed at the surface, allowing for the cost-effective collection of large-sized old-ice samples. However, chronostratigraphic studies on blue-ice areas are challenging owing to fold and fault structures. Here, we report on a surface transect of ice with an undisturbed horizontal stratigraphy from the Larsen BIA, northern Victoria Land, East Antarctica. Ice layers defined by dust bands and ground-penetrating radar (GPR) surveys indicate a monotonic increase in age along the ice flow direction on the downstream side, while the upstream ice exhibits a potential repetition of ages on scales of tens of meters, which result from a complicated fold structure. Stable water isotopes (δ18Oice and δ2Hice) and components of the occluded air (i.e., CO2, N2O, CH4, δ15N–N2, δ18Oatm (=δ18O-O2), δO2/N2, δAr/N2​​​​​​​, 81Kr, and 85Kr) are analyzed for surface ice and shallow ice core samples. Correlating δ18Oice, δ18Oatm, and CH4 records from the Larsen BIA with ice from previously drilled ice cores indicates that the gas age at various shallow vertical coring sites ranges between 9.2–23.4 kyr BP, while the ice age sampled from the surface ranges from 5.6 to 24.7 kyr BP. Absolute radiometric 81Kr dating for the two vertical cores confirms ages within acceptable levels of analytical uncertainty. A tentative climate reconstruction suggests a large deglacial warming of 15 ± 5 ∘C (1σ) and an increase in snow accumulation by a factor of 1.7–4.6 (from 24.3 to 10.6 kyr BP). Our study demonstrates that BIAs in northern Victoria Land may help to obtain high-quality records for paleoclimate and atmospheric greenhouse gas compositions through the last deglaciation, although in general climatic interpretation is complicated by the need for upstream flow corrections, evidence for strong surface sublimation during the last glacial period, and potential errors in the estimated gas age–ice age difference.</p

Attenuation curves of neutrons from 400 to 550 Mev/u for Ca, Kr, Sn, and U ions in concrete on a graphite target for the design of shielding for the RAON in-flight fragment facility in Korea

Rare isotope beam facilities require shielding data in early stage of their design. There is much less shielding data on neutrons from the reactions between heavy ion beams and matter than the data on neutrons produced by protons. The purpose of the present work is to produce and thus increase the amount of shielding data on neutrons generated by high-energy heavy ion beams based on the RAON in-flight fragment facility. Calculations were performed with the computational Monte Carlo codes PHITS and MCNPX. The secondary neutron source terms were evaluated at 550 MeV/u for Ca, Kr, and Sn and at 400 MeV/u for U ions on a graphite target. Source terms and attenuation lengths were obtained by fitting the ambient dose equivalent inside an ordinary concrete shield. Keywords: Heavy ion accelerator, Shielding data, Neutron attenuation, Monte Carl

FPGA-Based Ordered Statistic Decoding Architecture for B5G/6G URLLC IIOT Networks

The ordered statistic decoding (OSD) approach for short-length BCH codes has been continuously considered as one of the promising error-correction codes by achieving a block error rate (BLER) of less than 10^{-6}, which is attractive to the ultra-reliable and low-latency communication (URLLC) for industrial IoT (IIOT) solutions [1], [2]. However, it is hard to directly realize the conventional OSD algorithm because of the compute-intensive Gaussian elimination and iterative reprocessing steps. Based on the recent segmentation discarding decoding (SDD) approach [3], in this work, we newly present an ultralow-latency OSD architecture reducing the decoding latency by 12 times, which is implemented at an FPGA-based verification platform.1

CO2 in ice cores at core depth 1.95 m from Larsen blue ice area, East Antarctica

Blue ice areas (BIAs) have several advantages for reconstructing past climate. However, the complicated ice flow in the areas hinders constraining the age. We apply state-of-the-art techniques and show that the ages cover the last deglaciation for Larsen BIA. Our study demonstrates that Larsen BIA in Northern Victoria Land helps in reconstructing the past climate during the last deglaciation. This data set presents gas composition (CO2, CH4, N2O, δ18Oatm, δ15N-N2, δO2/N2, δAr/N2), stable water isotopes (δ2Hice, δ18Oice), and the chronology of Larsen BIA. The ice cores were collected in January 2019 in Northern Victoria Land, East Antarctica. Gas composition analysis was conducted at Seoul National University and National Institute of Polar Research. Stable water isotopes were analyzed at Korea Polar Research Institute. Data sets were also published as a supplement of Lee et al. (2022) titled with “Chronostratigraphy of Larsen blue ice area in Northern Victoria Land, East Antarctica, and its implications for paleoclimate”, The Cryosphere

CO2 in ice core #23 from Larsen blue ice area, East Antarctica

Blue ice areas (BIAs) have several advantages for reconstructing past climate. However, the complicated ice flow in the areas hinders constraining the age. We apply state-of-the-art techniques and show that the ages cover the last deglaciation for Larsen BIA. Our study demonstrates that Larsen BIA in Northern Victoria Land helps in reconstructing the past climate during the last deglaciation. This data set presents gas composition (CO2, CH4, N2O, δ18Oatm, δ15N-N2, δO2/N2, δAr/N2), stable water isotopes (δ2Hice, δ18Oice), and the chronology of Larsen BIA. The ice cores were collected in January 2019 in Northern Victoria Land, East Antarctica. Gas composition analysis was conducted at Seoul National University and National Institute of Polar Research. Stable water isotopes were analyzed at Korea Polar Research Institute. Data sets were also published as a supplement of Lee et al. (2022) titled with “Chronostratigraphy of Larsen blue ice area in Northern Victoria Land, East Antarctica, and its implications for paleoclimate”, The Cryosphere

Temperature and accumulation rate in ice cores from Larsen blue ice area, East Antarctica

Blue ice areas (BIAs) have several advantages for reconstructing past climate. However, the complicated ice flow in the areas hinders constraining the age. We apply state-of-the-art techniques and show that the ages cover the last deglaciation for Larsen BIA. Our study demonstrates that Larsen BIA in Northern Victoria Land helps in reconstructing the past climate during the last deglaciation. This data set presents gas composition (CO2, CH4, N2O, δ18Oatm, δ15N-N2, δO2/N2, δAr/N2), stable water isotopes (δ2Hice, δ18Oice), and the chronology of Larsen BIA. The ice cores were collected in January 2019 in Northern Victoria Land, East Antarctica. Gas composition analysis was conducted at Seoul National University and National Institute of Polar Research. Stable water isotopes were analyzed at Korea Polar Research Institute. Data sets were also published as a supplement of Lee et al. (2022) titled with “Chronostratigraphy of Larsen blue ice area in Northern Victoria Land, East Antarctica, and its implications for paleoclimate”, The Cryosphere

Ice age uncertainty in ice cores from Larsen blue ice area, East Antarctica

Blue ice areas (BIAs) have several advantages for reconstructing past climate. However, the complicated ice flow in the areas hinders constraining the age. We apply state-of-the-art techniques and show that the ages cover the last deglaciation for Larsen BIA. Our study demonstrates that Larsen BIA in Northern Victoria Land helps in reconstructing the past climate during the last deglaciation. This data set presents gas composition (CO2, CH4, N2O, δ18Oatm, δ15N-N2, δO2/N2, δAr/N2), stable water isotopes (δ2Hice, δ18Oice), and the chronology of Larsen BIA. The ice cores were collected in January 2019 in Northern Victoria Land, East Antarctica. Gas composition analysis was conducted at Seoul National University and National Institute of Polar Research. Stable water isotopes were analyzed at Korea Polar Research Institute. Data sets were also published as a supplement of Lee et al. (2022) titled with “Chronostratigraphy of Larsen blue ice area in Northern Victoria Land, East Antarctica, and its implications for paleoclimate”, The Cryosphere

Ice surface measurements from Larsen blue ice area, East Antarctica

Blue ice areas (BIAs) have several advantages for reconstructing past climate. However, the complicated ice flow in the areas hinders constraining the age. We apply state-of-the-art techniques and show that the ages cover the last deglaciation for Larsen BIA. Our study demonstrates that Larsen BIA in Northern Victoria Land helps in reconstructing the past climate during the last deglaciation. This data set presents gas composition (CO2, CH4, N2O, δ18Oatm, δ15N-N2, δO2/N2, δAr/N2), stable water isotopes (δ2Hice, δ18Oice), and the chronology of Larsen BIA. The ice cores were collected in January 2019 in Northern Victoria Land, East Antarctica. Gas composition analysis was conducted at Seoul National University and National Institute of Polar Research. Stable water isotopes were analyzed at Korea Polar Research Institute. Data sets were also published as a supplement of Lee et al. (2022) titled with “Chronostratigraphy of Larsen blue ice area in Northern Victoria Land, East Antarctica, and its implications for paleoclimate”, The Cryosphere

Chronology, gas composition (CO2, CH4, N2O, δ18Oatm, δ15N-N2, δO2/N2, δAr/N2), and stable water isotopes (δ2Hice, δ18Oice) in ice cores from Larsen blue ice area, East Antarctica

Blue ice areas (BIAs) have several advantages for reconstructing past climate. However, the complicated ice flow in the areas hinders constraining the age. We apply state-of-the-art techniques and show that the ages cover the last deglaciation for Larsen BIA. Our study demonstrates that Larsen BIA in Northern Victoria Land helps in reconstructing the past climate during the last deglaciation. This data set presents gas composition (CO2, CH4, N2O, δ18Oatm, δ15N-N2, δO2/N2, δAr/N2), stable water isotopes (δ2Hice, δ18Oice), and the chronology of Larsen BIA. The ice cores were collected in January 2019 in Northern Victoria Land, East Antarctica. Gas composition analysis was conducted at Seoul National University and National Institute of Polar Research. Stable water isotopes were analyzed at Korea Polar Research Institute. Data sets were also published as a supplement of Lee et al. (2022) titled with “Chronostratigraphy of Larsen blue ice area in Northern Victoria Land, East Antarctica, and its implications for paleoclimate”, The Cryosphere

Properties of ice core #23 from Larsen blue ice area, East Antarctica

Blue ice areas (BIAs) have several advantages for reconstructing past climate. However, the complicated ice flow in the areas hinders constraining the age. We apply state-of-the-art techniques and show that the ages cover the last deglaciation for Larsen BIA. Our study demonstrates that Larsen BIA in Northern Victoria Land helps in reconstructing the past climate during the last deglaciation. This data set presents gas composition (CO2, CH4, N2O, δ18Oatm, δ15N-N2, δO2/N2, δAr/N2), stable water isotopes (δ2Hice, δ18Oice), and the chronology of Larsen BIA. The ice cores were collected in January 2019 in Northern Victoria Land, East Antarctica. Gas composition analysis was conducted at Seoul National University and National Institute of Polar Research. Stable water isotopes were analyzed at Korea Polar Research Institute. Data sets were also published as a supplement of Lee et al. (2022) titled with “Chronostratigraphy of Larsen blue ice area in Northern Victoria Land, East Antarctica, and its implications for paleoclimate”, The Cryosphere