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We performed stochastic and deterministic calculations to study simple bimolecular chemical kinetics with a neighborhood, necessary for solid‐state and viscous medium reactions. Regarding the standard deterministic method using ordinary differential equations (ODEs) to describe a bimolecular reaction with the neighborhood, we established a comparison that indicates, in this method, an implicit diffusion process. For example, the reaction is processed in a homogeneous medium, differently from the stochastic method without diffusion. The two methods coincide at the thermodynamic limit (containing little relative fluctuation) when added with the explicit diffusion process on the stochastic model. The irreversible reaction without diffusion was emulated using the ODEs of a reversible reaction, and the inherent residual concentration of the reactions with low or no diffusion occurring in solids or strong viscous media was obtained from pseudochemical equilibrium. [ABSTRACT FROM AUTHOR]

This paper addresses the estimation of the sea-air CO2 flux based on a commonly used bulk formula in terms of the mean wind speed at the 10-meter (10-m) elevation above the sea surface. Results are exemplified by using data on long-term mean wind speed statistics from the North Sea, the North Atlantic, and the North West Shelf of Australia. The present method can be used to estimate and assess the sea-air CO2 flux based on e.g. global wave statistics. [ABSTRACT FROM AUTHOR]

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During the prereservoir years, when limited data (neighboring basin flow and simulated flow) are available for ungauged basins, simple methods are relevant to reconstruct natural flow (NF). On the other hand, for the postreservoir years, when hydrometric data (water level in the reservoir, turbine flow, and discharged flow) are available for ungauged basins, the classic water balance equation (WBE) method is usually employed to determine NF. However, applying classic methods still produce noisy and unreliable flow data series. In an attempt to produce more reliable NF data, new methods are proposed and described in Part 1 of this paper: the state fusion Kalman filter method (prereservoir construction period) and the deterministic WBE method and the stochastic WBE method (postreservoir construction period). This paper that is presented as Part 2 deals with the execution of these new methods for three subbasins of different sizes in Quebec, Canada. Obtained results are then compared against those produced by the use of the current methods of NF reconstruction: area ratio method, maintenance of variance (Move) type III method, and multivariable regression method (prereservoir construction period), and the classic WBE model (postreservoir construction period). This comparative analysis shows the capability of proposed methods for improving the constructed data series with improved results that do not contain any negative flow. They are less noisy, perfectly matched with regional flows, and are reliable enough for frequency analyses. Because these NF values include evaporation, infiltration, and other losing terms of a closed hydraulic system, with more studies needed in order to define the contribution of each of them. [ABSTRACT FROM AUTHOR]

Because natural flow (NF) values are either not directly measured or have the potential to contain considerable error, when deemed necessary, the reconstruction of a reliable NF series is ostensibly important. Selecting the appropriate method depends on available data. For a time period before reservoir construction (pre-reservoir construction period), the only available data for ungauged basins came from the neighboring basins and simulated flow used in a rainfall-runoff model. A new Kalman-based method developed in this paper looks to reconstruct the NF series using the state fusion technique, which is then compared with the area ratio method, the maintenance of variance (Move) type III method, and the multivariable regression method using different quality indexes (QIs). In the perspective of the post-reservoir construction period, when hydrometric data (i.e., turbine flow, water level in the reservoir, and discharged flow) is collected in an ungauged basin (with no flow measurements), a new water balance equation (WBE)-based method is recommended for reconstructing and filtering the NF data using an optimization technique that would then be compared with the classic WBE that implements different QIs. [ABSTRACT FROM AUTHOR]