The design of efficient air pollution control strategies

This statement addresses gains in economic efficiency which could be obtained by removing barriers to advances in the technology and procedures commonly used for designing air pollution abatement strategies

Compatible finite element methods for numerical weather prediction

This article takes the form of a tutorial on the use of a particular class of mixed finite element methods, which can be thought of as the finite element extension of the C-grid staggered finite difference method. The class is often referred to as compatible finite elements, mimetic finite elements, discrete differential forms or finite element exterior calculus. We provide an elementary introduction in the case of the one-dimensional wave equation, before summarising recent results in applications to the rotating shallow water equations on the sphere, before taking an outlook towards applications in three-dimensional compressible dynamical cores.Comment: To appear in ECMWF Seminar proceedings 201

Auxin-induced growth inhibition a natural consequence of two-point attachment

It is characteristic of a great number of biologically active substances that the responses which they elicit are twofold, low concentrations of the material promoting a particular activity, and higher concentrations inhibiting it. This is the case with the auxin-induced growth responses of plants. An active auxin such as indole acetic acid (IAA) brings about and is essential to growth in length of stems, hypocotyls and other plant organs including the Avena coleoptile

An Objective Analysis Technique for Constructing Three-Dimensional Urban-Scale Wind Fields

An objective analysis procedure for generating mass-consistent, urban-scale three-dimensional wind fields is presented together with a comparison against existing techniques. The algorithm employs terrain following coordinates and variable vertical grid spacing. Initial estimates of the velocity field are developed by interpolating surface and upper level wind measurements. A local terrain adjustment technique, involving solution of the Poisson equation, is used to establish the horizontal components of the surface field. Vertical velocities are developed from successive solutions of the continuity equation followed by an iterative procedure which reduces anomalous divergence in the complete field. Major advantages of the procedure are that it is computationally efficient and allows boundary values to adjust in response to changes in the interior flow. The method has been successfully tested using field measurements and problems with known analytic solutions

Mathematical modeling of photochemical air pollution

This paper summarizes the key elements of a project directed at developing a comprehensive mathematical model capable of describing the formation and transport of chemically reacting species in the turbulent planetary boundary layer. The model is intended for routine application in the design and evaluation of urban-scale air pollution control strategies. Some examples illustrating the use of the model in the South Coast Air Basin of Southern California are presented

La stabilité des prix des ressources non renouvelables

One particular problem with the competitive solution to resource pricing is the potential for resource price instability. Using monthly data on prices for five different minerals the author examines, with the help of statistical techniques, the behaviour of prices over the years 1922-1974. He finds that fears of potential resource price instability have been overstated. Due either to the capitalization reactions of resource owners, or to the fact that resource markets are characterized by a monopolized industrial structure, real resource prices appear to show remarkable stability

Remembering Rebellion, Remembering Resistance: Collective Memory, Identity, and the Veterans of 1869-70 and 1885

This dissertation analyses two of the Canadian state’s earliest military operations through the lens of personal and collective memory: The Red River conflict of 1869-70 and the Northwest Campaign of 1885. Both campaigns were directed by the Canadian state against primarily Métis and First Nations opponents. In each case, resistance to Canadian hegemony was centered on, though not exclusively led by, Métis leader Louis Riel. This project focuses on the various veteran communities that were created in the aftermath of these two events. On one side, there were the Canadian government soldiers who had served in the campaigns and were initially celebrated by English-Canadian society. On the other side, there were Métis and First Nations warriors who had resisted the state. They were largely forgotten by the English-Canadian public, but still respected and commemorated within their own communities. This dynamic changed in the latter part of the twentieth century. After the last Canadian militia veterans passed away in the 1950s, they quickly faded from English-Canadian collective memory. At the same time, calls from Métis and First Nations peoples for greater recognition of their veterans began to receive more attention. By the end of the twentieth century, the narrative of the Canadian militia veterans had all but disappeared, but was not replaced in English Canada with a narrative of Indigenous veterans. The efforts of these veteran communities to promote particular visions of the past speaks to questions of national identity that still persist today