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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]

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]

When Dr. Adam Rotunda '96 visited his clinical professor's dermatology practice, he was fascinated by a set of photographs. As a young UCLA dermatology resident focusing on skin cancer surgery, [...]

Last fall, Professor Sean Nicholson, director of the Sloan Program in Health Administration, and Arnaub Chatterjee, MHA/MPA '07, pictured above, launched a new course: a health care information technology (HIT) [...]

Mike Pisco '06, policy analysis and management, and his wife Kathryn, CALS '05, resigned from their corporate jobs on the same day. A month later, in February 2013, they used [...]

As the youngest of three, Tiffany Goh '07 didn't spend too long on her college search. After all, she'd already visited Cornell, and seen the breadth of experiences her sisters [...]

Edgar Akuffo-Addo '16 is dreaming big in order to bring health equity to his native Ghana and other developing countries. Last year, his vision came closer to reality when Projects [...]

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]

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.