26 research outputs found
Evolution of a Canada Basin ice-ocean boundary layer and mixed layer across a developing thermodynamically forced marginal ice zone
A comprehensive set of autonomous, ice-ocean measurements were collected across the Canada Basin to study the summer evolution of the ice-ocean boundary layer (IOBL) and ocean mixed layer (OML). Evaluation of local heat and freshwater balances and associated turbulent forcing reveals that melt ponds (MPs) strongly influence the summer IOBL-OML evolution. Areal expansion of MPs in mid-June start the upper ocean evolution resulting in significant increases to ocean absorbed radiative flux (19 W m−2 in this study). Buoyancy provided by MP drainage shoals and freshens the IOBL resulting in a 39 MJ m−2 increase in heat storage in just 19 days (52% of the summer total). Following MP drainage, a near-surface fresh layer deepens through shear-forced mixing to form the summer mixed layer (sML). In late summer, basal melt increases due to stronger turbulent mixing in the thin sML and the expansion of open water areas due in part to wind-forced divergence of the sea ice. Thermal heterogeneities in the marginal ice zone (MIZ) upper ocean led to large ocean-to-ice heat fluxes (100–200 W m−2) and enhanced basal ice melt (3–6 cm d−1), well away from the ice edge. Calculation of the upper ocean heat budget shows that local radiative heat input accounted for at least 89% of the observed latent heat losses and heat storage (partitioned 0.77/0.23). These results suggest that the extensive area of deteriorating sea ice observed away from the ice edge during the 2014 season, termed the “thermodynamically forced MIZ,” was driven primarily by local shortwave radiative forcing
Ice and ocean velocity in the Arctic marginal ice zone: Ice roughness and momentum transfer
The interplay between sea ice concentration, sea ice roughness, ocean stratification, and momentum transfer to the ice and ocean is subject to seasonal and decadal variations that are crucial to understanding the present and future air-ice-ocean system in the Arctic. In this study, continuous observations in the Canada Basin from March through December 2014 were used to investigate spatial differences and temporal changes in under-ice roughness and momentum transfer as the ice cover evolved seasonally. Observations of wind, ice, and ocean properties from four clusters of drifting instrument systems were complemented by direct drill-hole measurements and instrumented overhead flights by NASA operation IceBridge in March, as well as satellite remote sensing imagery about the instrument clusters. Spatially, directly estimated ice-ocean drag coefficients varied by a factor of three with rougher ice associated with smaller multi-year ice floe sizes embedded within the first-year-ice/multi-year-ice conglomerate. Temporal differences in the ice-ocean drag coefficient of 20–30% were observed prior to the mixed layer shoaling in summer and were associated with ice concentrations falling below 100%. The ice-ocean drag coefficient parameterization was found to be invalid in September with low ice concentrations and small ice floe sizes. Maximum momentum transfer to the ice occurred for moderate ice concentrations, and transfer to the ocean for the lowest ice concentrations and shallowest stratification. Wind work and ocean work on the ice were the dominant terms in the kinetic energy budget of the ice throughout the melt season, consistent with free drift conditions. Overall, ice topography, ice concentration, and the shallow summer mixed layer all influenced mixed layer currents and the transfer of momentum within the air-ice-ocean system. The observed changes in momentum transfer show that care must be taken to determine appropriate parameterizations of momentum transfer, and imply that the future Arctic system could become increasingly seasonal
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Towards microbiome-informed dietary recommendations for promoting metabolic and mental health: opinion papers of the MyNewGut project
The gut microbiota coexists in partnership with the human host through adaptations to environmental and physiological changes that help maintain dynamic homeostatic healthy states. Break-down of this delicate balance under sustained exposure to stressors (e.g. unhealthy diets) can, however, contribute to the onset of disease. Diet is a key modifiable environmental factor that modulates the gut microbiota and its metabolic capacities that, in turn, could impact human physiology. On this basis, the diet and the gut microbiota could act as synergistic forces that provide resilience against disease or that speed the progress from health to disease states. Associations between unhealthy dietary patterns, non-communicable diseases and intestinal dysbiosis can be explained by this hypothesis. Translational studies showing that dietary-induced alterations in microbial communities recapitulate some of the pathological features of the original host further support this notion. In this introductory paper by the European project MyNewGut, we briefly summarize the investigations conducted to better understand the role of dietary patterns and food components in metabolic and mental health and the specificities of the microbiome-mediating mechanisms. We also discuss how advances in the understanding of the microbiome's role in dietary health effects can help to provide acceptable scientific grounds on which to base dietary advice for promoting healthy living
Evolution of a Canada Basin ice‐ocean boundary layer and mixed layer across a developing thermodynamically forced marginal ice zone
The article of record as published may be found at http://dx.doi.org/10.1002/2016JC011778A comprehensive set of autonomous, ice-ocean measurements were collected across the Canada Basin to study the summer evolution of the ice-ocean boundary layer (IOBL) and ocean mixed layer (OML). Evaluation of local heat and freshwater balances and associated turbulent forcing reveals that melt ponds (MPs) strongly influence the summer IOBL-OML evolution. Areal expansion of MPs in mid-June start the upper ocean evolution resulting in significant increases to ocean absorbed radiative flux (19 W m22 in this study). Buoyancy provided by MP drainage shoals and freshens the IOBL resulting in a 39 MJ m22 increase in heat storage in just 19 days (52% of the summer total). Following MP drainage, a near-surface fresh layer deepens through shear-forced mixing to form the summer mixed layer (sML). In late summer, basal melt increases due to stronger turbulent mixing in the thin sML and the expansion of open water areas due in part to wind-forced divergence of the sea ice. Thermal heterogeneities in the marginal ice zone (MIZ) upper ocean led to large ocean-to-ice heat fluxes (100�200 W m22) and enhanced basal ice melt (3� 6 cm d21), well away from the ice edge. Calculation of the upper ocean heat budget shows that local radiative heat input accounted for at least 89% of the observed latent heat losses and heat storage (partitioned 0.77/0.23). These results suggest that the extensive area of deteriorating sea ice observed away from the ice edge during the 2014 season, termed the ��thermodynamically forced MIZ,�� was driven primarily by local shortwave radiative forcin
Learning through digitally-augmented physical experiences: Reflections on the ambient wood project.
“Fast and bulbous ”- In memory of Mike Scaife who was the inspiration and the instigator of the project Information Technology (IT) has become an ubiquitous part of education, with a wide range of software being developed and used nowadays to support children in their learning. A dominant model has been to provide information and learning material, that is accessed via the web through the use of desktop computers, in the classroom, the library or home. While the use of technology in this way is generally considered to be successful, it is limited in the kinds of learning activities that it supports. How else might we combine technology and information to extend learning? We report here on a very different approach, where we used a diversity of pervasive, hi-tech and mobile technologies to design a set of integrated, novel learning experiences, to take place outdoors in a wood. Our aim was to augment the physical environment with various forms of ambient digital information, such that children’s interactions and perceptions of it were extended in surprising and unusual ways. In so doing, our goal was to get children to take part and learn more about scientific enquiry, through discovering, reflecting and experimenting in an ambient wood
Choosing healthy eating for infant health (CHErIsH) study: protocol for a feasibility study
Introduction Childhood obesity is a public health
challenge. There is evidence for associations between
parents’ feeding behaviours and childhood obesity
risk. Primary care provides a unique opportunity for
delivery of infant feeding interventions for childhood
obesity prevention. Implementation strategies are
needed to support infant feeding intervention delivery.
The Choosing Healthy Eating for Infant Health (CHErIsH)
intervention is a complex infant feeding intervention
delivered at infant vaccination visits, alongside a
healthcare professional (HCP)-level implementation
strategy to support delivery.
Methods and analysis This protocol provides a
description of a non-randomised feasibility study of an
infant feeding intervention and implementation strategy,
with an embedded process evaluation and economic
evaluation. Intervention participants will be parents
of infants aged ≤6 weeks at recruitment, attending
a participating HCP in a primary care practice. The
intervention will be delivered at the infant’s 2, 4, 6, 12
and 13month vaccination visits and involves brief verbal
infant feeding messages and additional resources,
including a leaflet, magnet, infant bib and sign-posting
to an information website. The implementation strategy
encompasses a local opinion leader, HCP training delivered
prior to intervention delivery, electronic delivery prompts
and additional resources, including a training manual,
poster and support from the research team. An embedded
mixed-methods process evaluation will examine the
acceptability and feasibility of the intervention, the
implementation strategy and study processes including
data collection. Qualitative interviews will explore parent
and HCP experiences and perspectives of delivery
and receipt of the intervention and implementation
strategy. Self-report surveys will examine fidelity of
delivery and receipt, and acceptability, suitability and
comprehensiveness of the intervention, implementation
strategy and study processes. Data from electronic
delivery prompts will also be collected to examine
implementation of the intervention. A cost–outcome
description will be conducted to measure costs of the
intervention and the implementation strategy.
Ethics and dissemination This study received approval
from the Clinical Research Ethics Committee of the Cork Teaching Hospitals. Study findings will be disseminated via
peer-reviewed publications and conference presentations