Optimization of over-summer snow storage at midlatitudes and low elevation

Climate change, including warmer winter temperatures, a shortened snowfall season, and more rain-on-snow events, threatens nordic skiing as a sport. In response, oversummer snow storage, attempted primarily using woodchips as a cover material, has been successfully employed as a climate change adaptation strategy by high-elevation and/or high-latitude ski centers in Europe and Canada. Such storage has never been attempted at a site that is both low elevation and midlatitude, and few studies have quantified storage losses repeatedly through the summer. Such data, along with tests of different cover strategies, are prerequisites to optimizing snow storage strategies. Here, we assess the rate at which the volume of two woodchip-covered snow piles (each ∼ 200 m3), emplaced during spring 2018 in Craftsbury, Vermont (45° N and 360 m a.s.l.), changed. We used these data to develop an optimized snow storage strategy. In 2019, we tested that strategy on a much larger, 9300 m3 pile. In 2018, we continually logged air-to-snow temperature gradients under different cover layers including rigid foam, open-cell foam, and woodchips both with and without an underlying insulating blanket and an overlying reflective cover. We also measured ground temperatures to a meter depth adjacent to the snow piles and used a snow tube to measure snow density. During both years, we monitored volume change over the melt season using terrestrial laser scanning every 10- 14 d from spring to fall. In 2018, snow volume loss ranged from 0.29 to 2.81 m3 d-1, with the highest rates in midsummer and lowest rates in the fall; mean rates of volumetric change were 1.24 and 1.50 m3 d-1, 0.55 % to 0.72 % of initial pile volume per day. Snow density did increase over time, but most volume loss was the result of melting. Wet woodchips underlain by an insulating blanket and covered with a reflective sheet were the most effective cover combination for minimizing melt, likely because the aluminized surface reflected incoming short-wave radiation while the wet woodchips provided significant thermal mass, allowing much of the energy absorbed during the day to be lost by long-wave emission at night. The importance of the pile surface-area-tovolume ratio is demonstrated by 4-fold lower rates of volumetric change for the 9300 m3 pile emplaced in 2019; it lost \u3c 0:16 % of its initial volume per day between April and October, retaining ∼ 60 % of the initial snow volume over summer. Together, these data demonstrate the feasibility of oversummer snow storage at midlatitudes and low elevations and suggest efficient cover strategies

Framing the debate and taking positions on food allergen legislation:The 100 chefs incident on social media

Those suffering with food allergies and intolerances need to consider risk every day, and professional organisations are increasingly enrolled in this risk management venture (e.g. offering support, developing legislation, and enforcing laws). Following the release of new food allergen rules in the UK, the Daily Telegraph, a national broadsheet newspaper, published a letter and an article in March 2015 endorsed by 100 chefs criticising the legislation. The chefs felt that innovation and creativity were being harmed by the requirement to state the presence of 14 allergens in the dishes they cooked. Following the release, many food allergen-concerned consumers utilised social media to share their views. In this article we use qualitative research data, comments posted online and collected between 9 and 16 March 2015, to explore how claimants positioned themselves and others in the ensuing online debate, and how the debate itself was framed. The data included traditional news articles, online forum comments, individual Twitter posts, and Twitter discussions. We identified frames across the debate discourse that emphasised medical concerns around managing risks associated with food allergy/intolerance, the assignment of responsibility, fairness of access, the political nature of the debate, and the financial implications involved. We draw on Positioning Theory to illustrate how user-positions can be defined, redefined, and challenged in the light of new or varying information. Our findings have implications for understanding communication around managing food risks from both a consumer and business perspective, and understanding the progression of debates through both traditional and new media platforms

Impact of an Extreme Storm Event on River Corridor Bank Erosion and Phosphorus Mobilization in a Mountainous Watershed in the Northeastern United States

Movement of sediment, and associated phosphorus, from stream banks to freshwater lakes is predicted to increase with greater frequency of extreme precipitation events. This higher phosphorus load may accelerate harmful algal blooms in affected water bodies, such as Lake Champlain in Vermont, New York, and Québec. In the Mad River, a subwatershed in central Vermont\u27s Lake Champlain Basin, extreme flooding from Tropical Storm Irene in 2011 caused extensive erosion. We measured stream channel change along the main stem between 2008 and 2011 by digitizing available prestorm and poststorm aerial imagery. Soils were sampled post Irene at six active stream erosion sites, using an experimental design to measure differences in soil texture and phosphorus both with depth (90 cm) and distance from the stream. In addition to total phosphorus (TP), we determined bioavailable (soil test) phosphorus (STP) and the degree of phosphorus saturation (DPS). The six sites represented a 0.87-km length of stream bank that contributed an estimated 17.6 × 10 3 Mg of sediment and 15.8 Mg of TP, roughly the same as average annual watershed export estimates. At four sites, the STP and DPS were low and suggested little potential for short-term phosphorus release. At two agricultural sites where the lateral extent of erosion was high, imagery showed a clear loss of well-established riparian buffer. Present-day near-stream soils were elevated in STP and DPS. An increase in these extreme events will clearly increase sediment loads. There will also be increasing concentration of sediment phosphorus if stream banks continue to erode into actively managed agricultural fields

Modeling sediment mobilization using a distributed hydrological model coupled with a bank stability model

In addition to surface erosion, stream bank erosion and failure contributes significant sediment and sediment-bound nutrients to receiving waters during high flow events. However, distributed and mechanistic simulation of stream bank sediment contribution to sediment loads in a watershed has not been achieved. Here we present a full coupling of existing distributed watershed and bank stability models and apply the resulting model to the Mad River in central Vermont. We fully coupled the Bank Stability and Toe Erosion Model (BSTEM) with the Distributed Hydrology Soil Vegetation Model (DHSVM) to allow the simulation of stream bank erosion and potential failure in a spatially explicit environment. We demonstrate the model\u27s ability to simulate the impacts of unstable streams on sediment mobilization and transport within a watershed and discuss the model\u27s capability to simulate watershed sediment loading under climate change. The calibrated model simulates total suspended sediment loads and reproduces variability in suspended sediment concentrations at watershed and subbasin outlets. In addition, characteristics such as land use and road-to-stream ratio of subbasins are shown to impact the relative proportions of sediment mobilized by overland erosion, erosion of roads, and stream bank erosion and failure in the subbasins and watershed. This coupled model will advance mechanistic simulation of suspended sediment mobilization and transport from watersheds, which will be particularly valuable for investigating the potential impacts of climate and land use changes, as well as extreme events

Framing the debate and taking positions on food allergen legislation:The 100 chefs incident on social media

Those suffering with food allergies and intolerances need to consider risk every day, and professional organisations are increasingly enrolled in this risk management venture (e.g. offering support, developing legislation, and enforcing laws). Following the release of new food allergen rules in the UK, the Daily Telegraph, a national broadsheet newspaper, published a letter and an article in March 2015 endorsed by 100 chefs criticising the legislation. The chefs felt that innovation and creativity were being harmed by the requirement to state the presence of 14 allergens in the dishes they cooked. Following the release, many food allergen-concerned consumers utilised social media to share their views. In this article we use qualitative research data, comments posted online and collected between 9 and 16 March 2015, to explore how claimants positioned themselves and others in the ensuing online debate, and how the debate itself was framed. The data included traditional news articles, online forum comments, individual Twitter posts, and Twitter discussions. We identified frames across the debate discourse that emphasised medical concerns around managing risks associated with food allergy/intolerance, the assignment of responsibility, fairness of access, the political nature of the debate, and the financial implications involved. We draw on Positioning Theory to illustrate how user-positions can be defined, redefined, and challenged in the light of new or varying information. Our findings have implications for understanding communication around managing food risks from both a consumer and business perspective, and understanding the progression of debates through both traditional and new media platforms

Tweeting and Eating: The Effect of Links and Likes on Food-Hypersensitive Consumers’ Perceptions of Tweets

Moving on from literature that focuses on how consumers use social media and the benefits of organizations utilizing platforms for health and risk communication, this study explores how specific characteristics of tweets affect the way in which they are perceived. An online survey with 251 participants with self-reported food hypersensitivity (FH) took part in an online experiment to consider the impact of tweet characteristics on perceptions of source credibility, message credibility, persuasiveness, and intention to act upon the presented information. Positioning the research hypotheses within the framework of the Elaboration Likelihood Model and Uses and Gratifications Theory, the study explored motivations for using social media and tested the impact of the affordances of Twitter—(1) the inclusion of links and (2) the number of social validation indicators (likes and retweets). Having links accompanying tweets significantly increased ratings of the tweets’ message credibility, as well as persuasiveness of their content. Socially validated tweets had no effect on these same variables. Parents of FH children were found to utilize social media for social reasons more than hypersensitive adults; concern level surrounding a reaction did not appear to alter the level of use. Links were considered valuable in obtaining social media users to attend to useful or essential food health and risk information. Future research in this area can usefully consider the nature and the effects of social validation in relation to other social media platforms and with other groups

Public transport and town centre accessibility Full report

SIGLEAvailable from British Library Document Supply Centre-DSC:98/22133 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Public transport and town centre accessibility Summary report

SIGLEAvailable from British Library Document Supply Centre-DSC:98/22134 / BLDSC - British Library Document Supply CentreGBUnited Kingdo