Integrated Project Teams: The MoD's New Hot Potato?

Since the announcement of Smart Procurement, much has been written on the potential benefits that IPTs will hopefully bring. It is supposed that they will improve the interface with industry, create a better understanding of requirements and establish an environment where industry is motivated to perform and so reduce cost, risk and time into service while improving product quality. The formation of a team should provide continuity, consistency, flexibility and ~ increased performance due to the integration of a wide-range of functional activities and decision-making, as well as increased motivation. These may well be gallant objectives, but how achievable are they? What obstacles does the MoD face in the implementation of the IPTs? Have they grasped a 'hot potato'

Stability of supraglacial debris

Rock debris on the surface of ablating glaciers is not static, and is often transported across the ice surface as relief evolves during melt. This supraglacial debris transport has a strong influence on the spatial distribution of melt, and is implicated in the formation of hummocky glacial topography in deglaciated terrain. Furthermore, as icedammed lakes and ice-cored slopes become increasingly common in deglaciating watersheds, there is rising concern about hazards to humans and infrastructure posed by mass-wasting of ice-cored debris. The existing quantitative framework for describing these debris transport processes is limited, making it difficult to account for transport in mass balance, hazard assessment, and landscape development models. This paper develops a theoretical framework for assessing slope stability and gravitational mass transport in a debris-covered ice setting. Excess water pressure at the interface between ablating ice and lowering debris is computed by combining Darcy’s law with a meltwater balance. A limit-equilibrium slope stability analysis is then applied to hypothetical debris layers with end-member moisture conditions derived from a downslope meltwater balance that includes production and seepage. The resulting model system constrains maximum stable slope angles and lengths that vary with debris texture, thickness, and the rate of meltwater production. Model predictions are compared with field observations and with DEM-derived terrain metrics from two modern debris-covered glaciers on Mount Rainier, USA

Deformation of Debris-Ice Mixtures

Mixtures of rock debris and ice are common in high-latitude and high-altitude environments and are thought to be widespread elsewhere in our solar system. In the form of permafrost soils, glaciers, and rock glaciers, these debris-ice mixtures are often not static but slide and creep, generating many of the landforms and landscapes associated with the cryosphere. In this review, a broad range of field observations, theory, and experimental work relevant to the mechanical interactions between ice and rock debris are evaluated, with emphasis on the temperature and stress regimes common in terrestrial surface and near-surface environments. The first-order variables governing the deformation of debris-ice mixtures in these environments are debris concentration, particle size, temperature, solute concentration (salinity), and stress. A key observation from prior studies, consistent with expectations, is that debris-ice mixtures are usually more resistant to deformation at low temperatures than their pure end-member components. However, at temperatures closer to melting, the growth of unfrozen water films at ice-particle interfaces begins to reduce the strengthening effect and can even lead to profound weakening. Using existing quantitative relationships from theoretical and experimental work in permafrost engineering, ice mechanics, and glaciology combined with theory adapted from metallurgy and materials science, a simple constitutive framework is assembled that is capable of capturing most of the observed dynamics. This framework highlights the competition between the role of debris in impeding ice creep and the mitigating effects of unfrozen water at debris-ice interfaces

Quantitative Problem Solving in Natural Resources

This text is intended to support courses that bridge the divide between mathematics typically encountered in U.S. high school curricula and the practical problems that natural resource students might engage with in their disciplinary coursework and professional internships.https://lib.dr.iastate.edu/opentextbooks/1000/thumbnail.jp

Eelgrass Habitat Creation in Nantucket Harbor, Massachusetts

In response to eelgrass habitat losses associated with development and marine activities in and around Nantucket Harbor, a plan to restore a meadow by transplanting eelgrass to previously vegetated areas was developed in conjunction with the Nantucket Land Council. Over 6,000 eelgrass shoots were sustainably harvested from an extensive bed within the Harbor that was located just west of First Point and near the inlet to Nantucket Sound. Four weeks following collection, impacts from our collection were shown by a 24% decline in shoot density, but live eelgrass cover did not decline significantly. After 12 weeks, no effects of collecting could be measured at the donor site for shoot density or cover. Plants had difficulty establishing within the restoration area due in part to extensive phytoplankton and macroalgal blooms that dramatically shaded the transplants for the initial three months following transplanting. After the first growing season, few of the 6,000 plants had survived, but those plants that survived became well established and grew through the second growing season in 2011. The significance of the macroalgae was documented through estimates of percentage cover, whereas light measurements showed the decline in water clarity from phytoplankton blooms to less than 10% ambient. Combined with our planting and monitoring results, our observations suggest that reestablishment of eelgrass beds in Nantucket Harbor is not limited by the distribution of seedlings, but by shading from phytoplankton and macroalgal blooms that resulted in levels of light too low to support eelgrass establishment during the summer months in 2010

Wetlands Evaluation for Philbrick\u27s Pond Marsh Drainage Evaluation North Hampton, NH

Philbrick’s Pond is a lagoon type estuary that formed landward of barrier beach spits in North Hampton, NH. Its inlet was stabilized and restricted by the road that is now Route 1A or Ocean Boulevard. Water flow from the Gulf of Maine passes through a culvert running under Route 1A and into a small waterway and is further restricted as it runs through a clay pipe under an old trolley berm. The lagoon is characterized as a 29 acre tidal marsh. The goal of the overall project is to evaluate the condition and hydrology of the two restrictions recognizing the conflicting needs for improved drainage from upstream flooding and limiting tidal flooding associated with extreme (i.e., storm surge) and normal flooding events due to sea level rise. The tidal marsh itself is a resource held in the public trust and therefore should be protected from any negative impacts associated with current conditions or predicted impacts due to future alternatives that may be chosen by the Town and its residents. Ditching of the marsh in the mid twentieth century rerouted drainage paths (e.g., Chapel Brook) and has resulted in large areas of vegetation loss between ditches in the past 60 years, as first reported by Short in 1984. The objectives of this report on the tidal marsh are threefold: 1) to evaluate the health of the tidal marsh by comparing existing and new data in Philbrick’s Pond with conditions found in the Little River tidal marsh just to the south; 2) characterize the relative benefits to the tidal marsh for the hydraulic alternatives evaluated by the hydrologic modeling; and 3) recommend management actions to restore marsh health using small scale drainage improvements (also known as runneling)