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Physical features preserved in ice cores may provide unique records about past atmospheric variability. Linking the formation and preservation of these features and the atmospheric processes causing them is key to their interpretation as palaeoclimate proxies. We imaged ice cores from Law Dome, East Antarctica, using an intermediate layer core scanner (ILCS) and found that thin bubble-free layers (BFLs) occur multiple times per year at this site. The origin of these features is unknown. We used a previously developed age–depth scale in conjunction with regional accumulation estimated from atmospheric reanalysis data (ERA5) to estimate the year and month that the BFLs occurred, and then we performed seasonal and annual analysis to reduce the overall dating errors. We then investigated measurements of snow surface height from a co-located automatic weather station to determine snow surface features co-occurring with BFLs, as well as their estimated occurrence date. We also used ERA5 to investigate potentially relevant local/regional atmospheric processes (temperature inversions, wind scour, accumulation hiatuses and extreme precipitation) associated with BFL occurrence. Finally, we used a synoptic typing dataset of the southern Indian and southwest Pacific oceans to investigate the relationship between large-scale atmospheric patterns and BFL occurrence. Our results show that BFLs occur (1) primarily in autumn and winter, (2) in conjunction with accumulation hiatuses > 4 d, and (3) during synoptic patterns characterised by meridional atmospheric flow related to the episodic blocking and channelling of maritime moisture to the ice core site. Thus, BFLs may act as a seasonal marker (autumn/winter) and may indicate episodic changes in accumulation (such as hiatuses) associated with large-scale circulation. This study provides a pathway to the development of a new proxy for past climate in the Law Dome ice cores, specifically past snowfall conditions relating to synoptic variability over the southern Indian Ocean. [ABSTRACT FROM AUTHOR]

Physical features preserved in ice cores may provide unique records about past atmospheric variability. Linking the formation and preservation of these features and the atmospheric processes causing them is key to their interpretation as paleoclimate proxies. We imaged ice cores from Law Dome, East Antarctica using an Intermediate Layer Ice Core Scanner (ILCS) which shows that thin bubble-free layers (BFLs) occur multiple times per year at this site. The origin of these features is unknown. We used a previously developed age-depth scale in conjunction with regional accumulation estimated from atmospheric reanalysis data (ERA5) to estimate the year and month that the BFLs occurred, and then performed seasonal and annual analysis to reduce the overall dating errors. We then investigated measurements of snow surface height from a co-located automatic weather station to determine snow surface features co-occurring with BFLs, as well as their estimated occurrence date. We also used ERA5 to investigate potentially relevant local/regional atmospheric processes (temperature inversions, wind scour, accumulation hiatuses and extreme precipitation) associated with BFL occurrence. Finally, we used a synoptic typing dataset of the southern Indian and southwest Pacific Oceans to investigate the relationship between large scale atmospheric patterns and BFL occurrence. Our results show that BFLs occur (1) primarily in autumn and winter, (2) in conjunction with accumulation hiatuses >4 days, and (3) during synoptic patterns characterised by meridional atmospheric flow related to the episodic blocking and channeling of maritime moisture to the ice core site. Thus, BFLs may act as a seasonal marker (autumn/winter), and may indicate episodic changes in accumulation (such as hiatuses) associated with large-scale circulation. This study provides a pathway to the development of a new proxy for past climate in the Law Dome ice cores; specifically past snowfall conditions relating to synoptic variability over the southern Indian Ocean. [ABSTRACT FROM AUTHOR]

Physical features preserved in ice cores may provide unique records about past atmospheric variability. Linking the formation and preservation of these features and the atmospheric processes causing them is key to their interpretation as paleoclimate proxies. We imaged ice cores from Law Dome, East Antarctica using an Intermediate Layer Ice Core Scanner (ILCS) which shows that thin bubble-free layers (BFLs) occur multiple times per year at this site. The origin of these features is unknown. We used a previously developed age-depth scale in conjunction with regional accumulation estimated from atmospheric reanalysis data (ERA5) to estimate the year and month that the BFLs occurred, and then performed seasonal and annual analysis to reduce the overall dating errors. We then investigated measurements of snow surface height from a co-located automatic weather station to determine snow surface features co-occurring with BFLs, as well as their estimated occurrence date. We also used ERA5 to investigate potentially relevant local/regional atmospheric processes (temperature inversions, wind scour, accumulation hiatuses and extreme precipitation) associated with BFL occurrence. Finally, we used a synoptic typing dataset of the southern Indian and southwest Pacific Oceans to investigate the relationship between large scale atmospheric patterns and BFL occurrence. Our results show that BFLs occur (1) primarily in autumn and winter, (2) in conjunction with accumulation hiatuses >4 days, and (3) during synoptic patterns characterised by meridional atmospheric flow related to the episodic blocking and channeling of maritime moisture to the ice core site. Thus, BFLs may act as a seasonal marker (autumn/winter), and may indicate episodic changes in accumulation (such as hiatuses) associated with large-scale circulation. This study provides a pathway to the development of a new proxy for past climate in the Law Dome ice cores; specifically past snowfall conditions relating to synoptic variability over the southern Indian Ocean. [ABSTRACT FROM AUTHOR]

The discovery of Antarctica's deepest subglacial trough beneath the Denman Glacier, combined with high rates of basal melt at the grounding line, has caused significant concern over its vulnerability to retreat. Recent attention has therefore been focusing on understanding the controls driving Denman Glacier's dynamic evolution. Here we consider the Shackleton system, comprised of the Shackleton Ice Shelf, Denman Glacier, and the adjacent Scott, Northcliff, Roscoe and Apfel glaciers, about which almost nothing is known. We widen the context of previously observed dynamic changes in the Denman Glacier to the wider region of the Shackleton system, with a multi-decadal time frame and an improved biannual temporal frequency of observations in the last 7 years (2015–2022). We integrate new satellite observations of ice structure and airborne radar data with changes in ice front position and ice flow velocities to investigate changes in the system. Over the 60-year period of observation we find significant rift propagation on the Shackleton Ice Shelf and Scott Glacier and notable structural changes in the floating shear margins between the ice shelf and the outlet glaciers, as well as features indicative of ice with elevated salt concentration and brine infiltration in regions of the system. Over the period 2017–2022 we observe a significant increase in ice flow speed (up to 50 %) on the floating part of Scott Glacier, coincident with small-scale calving and rift propagation close to the ice front. We do not observe any seasonal variation or significant change in ice flow speed across the rest of the Shackleton system. Given the potential vulnerability of the system to accelerating retreat into the overdeepened, potentially sediment-filled bedrock trough, an improved understanding of the glaciological, oceanographic and geological conditions in the Shackleton system are required to improve the certainty of numerical model predictions, and we identify a number of priorities for future research. With access to these remote coastal regions a major challenge, coordinated internationally collaborative efforts are required to quantify how much the Shackleton region is likely to contribute to sea level rise in the coming centuries. [ABSTRACT FROM AUTHOR]

Ocean-driven melt of Antarctic ice shelves is an important control on mass loss from the ice sheet, but is complex to study due to significant variability in melt rates both spatially and temporally. Here we assess the strengths and weakness of satellite and field-based observations as tools for testing models of ice-shelf melt. We discuss how the complementary use of field, satellite and model data can be a powerful but underutilised tool for studying melt processes. Finally, we identify some community initiatives working to collate and publish coordinated melt rate datasets, which can be used in future for validating satellite-derived maps of melt and evaluating processes in numerical simulations. [ABSTRACT FROM AUTHOR]

Rock debris covers ~30% of glacier ablation areas in the Central Himalaya and modifies the impact of atmospheric conditions on mass balance. The thermal properties of supraglacial debris are diurnally variable but remain poorly constrained for monsoon-influenced glaciers over the timescale of the ablation season. We measured vertical debris profile temperatures at 12 sites on four glaciers in the Everest region with debris thickness ranging from 0.08 to 2.8 m. Typically, the length of the ice ablation season beneath supraglacial debris was 160 days (15 May to 22 October)—a month longer than the monsoon season. Debris temperature gradients were approximately linear (r2 > 0.83), measured as −40°C m–1 where debris was up to 0.1 m thick, −20°C m–1 for debris 0.1–0.5 m thick, and −4°C m–1 for debris greater than 0.5 m thick. Our results demonstrate that the influence of supraglacial debris on the temperature of the underlying ice surface, and therefore melt, is stable at a seasonal timescale and can be estimated from near-surface temperature. These results have the potential to greatly improve the representation of ablation in calculations of debris-covered glacier mass balance and projections of their response to climate change. [ABSTRACT FROM AUTHOR]

Supra-glacial lakes and ponds can create hotspots of mass loss on debris-covered glaciers. While much research has been directed at understanding lateral lake expansion, little is known about the rates or processes governing lake deepening. To a large degree, this knowledge gap persists due to sparse observations of lake beds. Here we report on the novel use of ground penetrating radar (GPR) surveys to simultaneously collect supra-glacial lake bathymetry and bottom composition data from Spillway Lake (surface area of 2.4 × 105 m2; volume of 9.5 × 104 m3), which is located in the terminus region of the Ngozumpa Glacier in the Khumbu region of the Nepal Himalaya. We identified two GPR bottom signals corresponding to two sedimentary facies of (1) sub-horizontal layered fine sediment drape and (2) coarse blocky diamict. We provide an understanding of the changes in subaqueous debris distribution that occur through stages of lake expansion by combining the GPR results with in situ observations of shoreline deposits matching the interpreted facies. From this, we present an updated conceptual model of supra-glacial lake evolution, with the addition of data on the evolving debris environment, showing how dominant depositional processes can change as lakes evolve from perched lakes to multi-basin base-level lakes and finally onto large moraine-dammed lakes. Throughout lake evolution, processes such as shoreline steepening, lakebed collapse into voids and conduit interception, subaerial and subaqueous calving and rapid areal expansion alter the spatial distribution and makeup of lakebed debris and sediments forcing a number of positive and negative feedbacks on lake expansion. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Moraine-dammed lakes at debris-covered glaciers are becoming increasingly common and pose significant outburst flood hazards if the dam is breached. While moraine subsurface structure and internal processes are likely to influence dam stability, only few sites have so far been investigated. We conducted electrical resistivity tomography (ERT) surveys at two sites on the terminal moraine complex of the Ngozumpa Glacier, Nepal, to aid assessment of future terminus stability. The resistivity signature of glacier ice at the site (100-15 kΩ m) is more consistent with values measured from cold glacier ice and while this may be feasible, uncertainties in the data inversion introduce ambiguity to this thermal interpretation. However, the ERT data does provide a significant improvement to our knowledge of the subsurface characteristics at these sites, clearly showing the presence (or absence) of glacier ice. Our interpretation is that of a highly complex latero-terminal moraine, resulting from interaction between previous glacier advance, recession and outburst flooding. If the base-level Spillway Lake continues to expand to a fully formed moraine-dammed glacial lake, the degradation of the ice core could have implications for glacial lake outburst risk. [ABSTRACT FROM AUTHOR]

The article offers profile of dermatologist Adam Rotunda at University of California, Los Angeles, California, (UCLA) and his research work. It mentions his research on Kybella, the first injectable medication approved by the U.S. Food and Drug Administration that reduce fat under the chin. It also offer views of Rotunda who credits effort of Virginia Utermohlen, former associate professor in nutritional sciences, for encouraging him in his career.

The article focuses on a course launched by health care information technology (HIT) "boot camp" launched by Sean Nicholson, director of the Sloan Program in Health Administration at Cornell University, New York and Master of Health Administration (MHA) student at the college, Arnaub Chatterjee. It informs that the course has been designed for second-year MHA students to know them the way information technology transform health care.

This article features Mike Pisco, an alumni of the New York State College of Human Ecology, and his wife Kathryn and their volunteer travel venture, called Unearth the World. It discusses the impact of their nine-month trip around the world on their perception of global issues and the involvement of travelers and international nonprofits in their venture.

This article features sisters Alice, Nancy and Tiffany Goh and their success in career after graduating from the New York State College of Human Ecology. It discusses the career of Alice in financial services, Alice's leadership role with nonprofit educational organization Teach For All, the shift in career from medicine to global health by Nancy and the bond between the sisters despite their separate lives and careers.

The article focuses on the grassroots program, Enhancing Child Nutrition Through Animal Source Food Management (ENAM), created by undergraduate Edgar Akuffo-Addo and funded by Projects for Peace to establish a poultry farm in Gushegu, Ghana to provide families with affordable meat and eggs and raise funds for community education. It discusses the prevalence of protein deficiencies among children in Gushegu and the obstacles faced by Akuffo-Addo and his team in launching the project.