Wave hydrodynamics around a multi-functional artificial reef at Leirosa

This paper describes an application of the Boussinesq-type COULWAVE model to study the wave hydrodynamics in the vicinity of a multi-functional artificial reef (MFAR). This reef is under investigation and consists of a supplementary protection solution for the Leirosa sand dune system located at South of Figueira da Foz, on the Portuguese West coast. Such installation near the coastline is expected to contribute to enhance the surfing conditions in the area, protect the sand dune system in the surroundings of Leirosa beach, and increase its environmental value. Numerical calculations with the COULWAVE model were performed for four test cases, considering two reef geometries (differing in the reef angle) and two incident wave conditions (storm condition and a common wave condition). Comparisons between the results obtained, in terms of wave heights and breaking line positions allow us to assess the influence of the reef on the hydrodynamics near the beach and around the reef. Moreover, the reef performance was analysed in terms of surfability and coastal protection. The surfability parameters (breaker height, Iribarren number and peel angle) were calculated for each test case using the numerical wave heights, wave directions and wave breaking positions. Comparisons of parameters allow characterizing the most appropriate configuration of the reef to improve the surfing conditions in the study area. A methodology based on numerical free surface elevations and horizontal velocity components was developed to calculate wave directions, since this is not a direct output of the COULWAVE model. Concerning coastal protection, analyses of the mean currents around the reef were used together with observations of the velocity cells near the shoreline as an indication of the sediment transport.     

An equivalence factor between CO2 avoidedemissions and sequestration – description andapplications in forestry

Concern about the issue of permanence andreversibility of the effects of carbon sequestrationhas led to the need to devise accounting methods thatquantify the temporal value of storing carbon that hasbeen actively sequestered or removed from theatmosphere, as compared to carbon stored as a resultof activities taken to avoid emissions. This paperdescribes a method for accounting for the atmosphericeffects of sequestration-based land-use projects inrelation to the duration of carbon storage. Firstly,the time period over which sequestered carbon shouldbe stored in order to counteract the radiative forcingeffect of carbon emissions was calculated, based onthe residence time and decay pattern of atmosphericCO₂, its Absolute Global Warming Potential. Thistime period was called the equivalence time, andwas calculated to be approximately 55 years. From thisequivalence time, the effect of storage of 1 tCO₂ for 1 year was derived, and found to besimilar to preventing the effect of the emission of0.0182 tCO₂. Potential applications of thistonne.year figure, here called the equivalencefactor, are then discussed in relation to theestimation of atmospheric benefits over time ofsequestration-based land use projects.     

Recycling Expanded Polystyrene with a Biodegradable Solvent to Manufacture 3D Printed Prototypes and Finishing Materials for Construction

Journal of Polymers and the Environment - The amount of plastic waste generated is causing damage to the environment, such as sea and soil pollution, and one of the alternatives for disposing of...