Impact of ocean stratification on submarine melting of a major Greenland outlet glacier

Submarine melting is an important balance term for tidewater glaciers1,2 and recent observations point to a change in the submarine melt rate as a potential trigger for the widespread acceleration of outlet glaciers in Greenland3-5. Our understanding of the dynamics involved, and hence our ability to interpret past and predict future variability of the Greenland Ice Sheet, however, is severely impeded by the lack of measurements at the ice/ocean interface. To fill this gap, attempts to quantify the submarine melt rate and its variability have relied on a paradigm developed for tidewater glaciers terminating in fjords with shallow sills. In this case, the fjords’ waters are mostly homogeneous and the heat transport to the terminus, and hence the melt rate, is controlled by a single overturning cell in which glacially modified water upwells at the ice edge, driving an inflow at depth and a fresh outflow at the surface1. Greenland’s fjords, however, have deep sills which allow both cold, fresh Arctic and warm, salty Atlantic waters, circulating around Greenland, to reach the ice sheet margin3,6,7. Thus, Greenland’s glaciers flow into strongly stratified fjords and the generic tidewater glacier paradigm is not applicable. Here, using new summer data collected at the margins of Helheim Glacier, East Greenland, we show that melting is driven by both Atlantic and Arctic waters and that the circulation at the ice edge is organized in multiple, overturning cells that arise from their different properties. Multiple cells with different characteristics are also observed in winter, when glacial run off is at a minimum and there is little surface outflow. These results indicate that stratification in the fjord waters has a profound impact on the melting dynamics and suggest that the shape and stability of Greenland’s glaciers are strongly influenced by layering and variability in the Arctic and Atlantic waters. 

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Time series measurements of transient tracers and tracer-derived transport in the Deep Western Boundary Current between the Labrador Sea and the subtropical Atlantic Ocean at Line W

Author Posting. © American Geophysical Union, 2016. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 121 (2016): 8115–8138, doi:10.1002/2016JC011759.Time series measurements of the nuclear fuel reprocessing tracer 129I and the gas ventilation tracer CFC-11 were undertaken on the AR7W section in the Labrador Sea (1997–2014) and on Line W (2004–2014), located over the US continental slope off Cape Cod, to determine advection and mixing time scales for the transport of Denmark Strait Overflow Water (DSOW) within the Deep Western Boundary Current (DWBC). Tracer measurements were also conducted in 2010 over the continental rise southeast of Bermuda to intercept the equatorward flow of DSOW by interior pathways. The Labrador Sea tracer and hydrographic time series data were used as input functions in a boundary current model that employs transit time distributions to simulate the effects of mixing and advection on downstream tracer distributions. Model simulations of tracer levels in the boundary current core and adjacent interior (shoulder) region with which mixing occurs were compared with the Line W time series measurements to determine boundary current model parameters. These results indicate that DSOW is transported from the Labrador Sea to Line W via the DWBC on a time scale of 5–6 years corresponding to a mean flow velocity of 2.7 cm/s while mixing between the core and interior regions occurs with a time constant of 2.6 years. A tracer section over the southern flank of the Bermuda rise indicates that the flow of DSOW that separated from the DWBC had undergone transport through interior pathways on a time scale of 9 years with a mixing time constant of 4 years.US NSF supported this work. Grant Numbers: OCE-0241354, OCE-0726720, OCE-0926848, OCE13-328342017-05-1

TP53-inducible Glycolysis and Apoptosis Regulator (TIGAR) Metabolically Reprograms Carcinoma and Stromal Cells in Breast Cancer.

A subgroup of breast cancers has several metabolic compartments. The mechanisms by which metabolic compartmentalization develop in tumors are poorly characterized. TP53 inducible glycolysis and apoptosis regulator (TIGAR) is a bisphosphatase that reduces glycolysis and is highly expressed in carcinoma cells in the majority of human breast cancers. Hence we set out to determine the effects of TIGAR expression on breast carcinoma and fibroblast glycolytic phenotype and tumor growth. The overexpression of this bisphosphatase in carcinoma cells induces expression of enzymes and transporters involved in the catabolism of lactate and glutamine. Carcinoma cells overexpressing TIGAR have higher oxygen consumption rates and ATP levels when exposed to glutamine, lactate, or the combination of glutamine and lactate. Coculture of TIGAR overexpressing carcinoma cells and fibroblasts compared with control cocultures induce more pronounced glycolytic differences between carcinoma and fibroblast cells. Carcinoma cells overexpressing TIGAR have reduced glucose uptake and lactate production. Conversely, fibroblasts in coculture with TIGAR overexpressing carcinoma cells induce HIF (hypoxia-inducible factor) activation with increased glucose uptake, increased 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3), and lactate dehydrogenase-A expression. We also studied the effect of this enzyme on tumor growth. TIGAR overexpression in carcinoma cells increases tumor growth in vivo with increased proliferation rates. However, a catalytically inactive variant of TIGAR did not induce tumor growth. Therefore, TIGAR expression in breast carcinoma cells promotes metabolic compartmentalization and tumor growth with a mitochondrial metabolic phenotype with lactate and glutamine catabolism. Targeting TIGAR warrants consideration as a potential therapy for breast cancer

HYDROBASE : a database of hydrographic stations and tools for climatological analysis

This report documents the organization, functionality, and algorithms of a software package which operates as a database manager and toolset for climatological analysis of hydrographic station data. It details the methods of quality control used in constrction of the small, but growing, database and discusses some of the improvements HydroBase methods offer over existing gridded databases, including a short comparison to Levitus's World Ocean Atlas 1994 package. A large porton of this technical reference is devoted to describing the software modules and providing examples for their use.Funding was provided by the National Science Foundation through Grant OCE91-03364 and the National Oceanic and Atmospheric Administration through Contract Nos. NA36GP0137 and NA46GP0303

Care and State Pension Reform - Interactions between state and pension long-term care reforms: a summary of findings

In April 2016 major reforms to state pensions were implemented in Great Britain. Reforms to the English long-term care financing system were also to be introduced in 2016 but have been postponed until 2020. The state pension reforms replace the existing two-tier state pension system with a single tier pension set just above the minimum income guaranteed through means-tested benefits. It affects only people reaching State Pension age from April 2016. The long-term care reforms introduce a cap on lifetime liability for care costs. To reach the cap, people will need to have eligible care needs for a considerable period, typically at least three years. The primary objective of the state pension reforms is to provide a clearer foundation for private pension saving and reduce reliance on means-tested benefits in retirement by setting the level of the new State Pension (nSP) above the level of the minimum income guaranteed by the means-tested benefit Pension Credit. The long-term care reforms introduce a lifetime limit on individual liability for care costs to provide protection against the risk that care costs could use up nearly all of an individual’s savings. The long-term effects of both sets of reforms will depend on how details of the systems are set in the intervening years, and in particular how components of the systems are adjusted each year – ‘uprated’ – for inflation. This report summarises the findings from a research project which aims to promote informed debate on how the reforms could evolve, highlighting the interactions between the two systems. Amongst other things, the study has analysed the impact of the reforms to 2030 under uprating assumptions consistent with current policy and under alternative uprating assumptions. A separate more detailed Technical Report of the analysis is available

‘It’s like equality now; it’s not as if it’s the old days’: an investigation into gender identity development and football participation of adolescent girls

This article explores the influence participating in football has on the development of adolescent girls’ gender identity, an area which currently lacks academic attention. Data were taken from an ethnographic study with a group of adolescent girls and boys and compared to Jeanes’ research. A social constructionist framework was deployed with links to both critical theory and feminist literature. Qualitative and participatory methods were used to fully engage with the complex issue of gender identity. The girls within this study were aware of the normative gender expectations linked to ‘being a female’ but did not find this restrictive. The girls moved between many changing identities and organised their ‘web of selves’ accordingly. The apparent need to measure success by the parameters of male standards created a barrier to girls’ identity development

Interactions between state pension and long-term care reforms: an overview

In April 2016 major reforms to state pensions and long-term care will be implemented in Great Britain and England respectively. Their combined effects have received little attention despite interactions between the two systems. The long-term effects of both sets of reforms will depend on how details of the systems are set in the intervening years, and on how policies in other parts of the welfare system evolve. We will investigate the long-term impacts of alternative ways in which current pensions and long-term care financing reforms may evolve over the next 40 years to ensure that that there is widespread appreciation of the implications of any changes which may have significant long-term effects