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Slug tests offer an efficient method for estimating the hydraulic parameters of an aquifer without water pumping. Two inverse methods are typically used to assess the slug test data and derive parameter estimates of a confined aquifer. The first method provides estimates of both hydraulic conductivity and specific storage, is visual (hence difficult to automate), and is based on the transient-flow analytical solution of Cooperet al.The second method, proposed by Hvorslev, is very straightforward, but provides only hydraulic conductivity estimates. In this study, we are testing the recently proposed quasi-steady method of Koussis and Akylas, which enables the estimation of both hydraulic parameters and, furthermore, can be easily implemented in computer code or an electronic spreadsheet. This quasi-steady method was coupled with the shuffled complex evolution optimization method to fully automate parameter estimation. This coupling is tested using data from field observations, synthetic data produced from the transient-flow analytical solution, and synthetic data with noise. The results show the usefulness and the limitations of the proposed method.Editor Z.W. Kundzewicz [ABSTRACT FROM AUTHOR]

The authors discuss the complete form of the extended Boussinesq equation. They mention the mathematical foundations of subsurface flow on a sloping base based on the Dupuit-Forchheimer theory of unconfined flow. They also mention the analytical steady-state solution of the nonlinear extended Boussinesq equation of Henderson and Wooding in 1964 and its linearisation solutions.

In this work, the two-point probability density function (PDF) for the velocity field of isotropic turbulence is modeled using the kappa distribution and the concept of superstatistics. The PDF consists of a symmetric and an anti-symmetric part, whose symmetry properties follow from the reflection symmetry of isotropic turbulence, and the associated non-trivial conditions are established. The symmetric part is modeled by the kappa distribution. The anti-symmetric part, constructed in the context of superstatistics, is a novel function whose simplest form (called "the minimal model") is solely dictated by the symmetry conditions. We obtain that the ensemble of eddies of size up to a given length r has a temperature parameter given by the second order structure function and a kappa-index related to the second and the third order structure functions. The latter relationship depends on the inverse temperature parameter (gamma) distribution of the superstatistics and it is not specific to the minimal model. Comparison with data from direct numerical simulations (DNS) of turbulence shows that our model is applicable within the dissipation subrange of scales. Also, the derived PDF of the velocity gradient shows excellent agreement with the DNS in six orders of magnitude. Future developments, in the context of superstatistics, are also discussed. [ABSTRACT FROM AUTHOR]

Seaborne movement underpins frontier research in prehistoric archaeology, including water-crossings in the context of human dispersals, and island colonisation. Yet, it also controls the degree of interaction between locations, which in turn is essential for investigating the properties of maritime networks. The onset of the Holocene (circa 12,000 years ago) is a critical period for understanding the origins of early visitors/inhabitants to the island of Cyprus in the Eastern Mediterranean in connection with the spread of Neolithic cultures in the region. The research undertaken in this work exemplifies the synergies between archaeology, physical sciences and geomatics, towards providing novel insights on the feasibility of drift-induced seaborne movement and the corresponding trip duration between Cyprus and coastal regions on the surrounding mainland. The overarching objective is to support archaeological inquiry regarding the possible origins of these visitors/inhabitants—Anatolia and/or the Levant being two suggested origins. [ABSTRACT FROM AUTHOR]

ROMS-AGRIF (Regional Ocean Model System, Adaptative Mesh Refinement In Fortran) is a free surface numerical ocean model that solves the primitive equation with the Boussinesq approximation with respect to hydrostatic vertical momentum balance. The model uses terrain-following vertical coordinates that allow differential stretching, within orthogonal, curvilinear, spherical horizontal coordinates. Equations are solved with short time steps for barotropic dynamic (ssh and 2D momentum) and a much larger time steps for baroclinic dynamic (T,S, 3D momentum) in a split explicit scheme. It uses rotated tensors to reduce diapycnal mixing and improved calculation of horizontal pressure gradient, following surface and bottom KPP turbulent closure model, thus obtaining high advection scheme. It uses adaptive mixed radiations/nudging open boundary conditions and it uses parallelization by two-dimensional subdomain partitioning, providing shared (OpenMP, as in our case) and distributed (MPI) parallelization. Also, it provides dynamic nesting capability with the AGRIF (Adaptive Grid Refinement in Fortran) library. It is an open source Fortran code coupled to several models including biogeochemistry, waves, sediments, bio-optical and sea ice. It offers great flexibility for configuration and is widely used by the scientific community for a diverse range of applications.ROMS-AGRIF version 3.1.1,(2014), has been applied on Eastern Mediterranean and, specifically, for first time over the Levantine and Cyprus Seas, covering the area that is defined by the geographical coordinates, 30.05º E to 36.25º E longitude and 30.99º N to 36.96º N latitude. The model's horizontal resolution is approximately 5.5km x 4.6km (122 XI x 142 ETA cell points) with an internal nested grid of 1.8km over the area defined by longitude 33.03 E to 34.06 E and latitude 33.68 N to 34.44 N (62 XI x 56 ETA cell points), at 30 vertical, terrain following, s-levels The model is using initial and boundary conditions from Marine Copernicus Portal data and surface fluxes from NOAA Global Forecast System. The grid has been created based on EMODNET Bathymetry portal data (tile 241). All data used are free open source.The model is running in operational prognostic mode, producing results every six hours, for a period of ten days, with daily averages included. Comparisons of the results with the CYCOFOS system (Cyprus Coastal Ocean Forecasting and Observing System) and with ARGOS float profiles shown compliance and very high accuracy. [ABSTRACT FROM AUTHOR]