Scope for a small circumsolar annular gravitational contribution to the Pioneer anomaly without affecting planetary orbits

All proposed gravitational explanations of the Pioneer anomaly must crucially face the Equivalence Principle. Thus, if Pioneers 10 and 11 were influenced by anomalous gravitational effects in regions containing other Solar System bodies, then those bodies should likewise be influenced, irrespective of their shape, composition or mass. Although the lack of any observed influence upon planetary orbits severely constrains such explanations, here we aim to construct by computer modeling, hypothetical gravitating annuli having no gravitational impact on planetary orbits from Mercury to Neptune. One model has a central zone, free of radial gravitation in the annular plane, and an ‘onset’ beyond Saturn’s orbit, where sunward annular gravitation increases to match the Pioneer anomaly data. Sharp nulls are included so that Uranus and Neptune escape this influence. Such models can be proportionately reduced in mass: a 1 % contribution to the anomaly requires an annulus of approximately 1 Earth mass. It is thus possible to comply with the JPL assessment of newly recovered data attributing 80 %, or more, of the anomaly to spacecraft heat, which appears to allow small contributions from other causes. Following the possibility of an increasing Kuiper belt density at great ranges, another model makes an outward small anomalous gravitation in the TNO region, tallying with an observed slight indication of such an effect, suggesting that New Horizons may slightly accelerate in this region.     

Effective macroscopic transport parameters between parallel plates with constant concentration boundaries

A macroscopic transport model is developed, following the Taylor shear dispersion analysis procedure, for a 2D laminar shear flow between parallel plates possessing a constant specified concentration. This idealized geometry models flow with contaminant dissolution at pore-scale in a contaminant source zone and flow in a rock fracture with dissolving walls. We upscale a macroscopic transient transport model with effective transport coefficients of mean velocity, macroscopic dispersion, and first-order mass transfer rate. To validate the macroscopic model the mean concentration, covariance, and wall concentration gradient are compared to the results of numerical simulations of the advection–diffusion equation and the Graetz solution. Results indicate that in the presence of local-scale variations and constant concentration boundaries, the upscaled mean velocity and macrodispersion coefficient differ from those of the Taylor–Aris dispersion, and the mass transfer flux described by the first-order mass transfer model is larger than the diffusive mass flux from the constant wall. In addition, the upscaled first-order mass transfer coefficient in the macroscopic model depends only on the plate gap and diffusion coefficient. Therefore, the upscaled first-order mass transfer coefficient is independent of the mean velocity and travel distance, leading to a constant pore-scale Sherwood number of 12. By contrast, the effective Sherwood number determined by the diffusive mass flux is a function of the Peclet number for small Peclet number, and approaches a constant of 10.3 for large Peclet number.     

The Longdendale landslides

Throughout its geomorphological history the South Pennine valley of Longdendale has been especially prone to landsliding and some ten landslide areas have been identified. These prove on analysis to be bedding plane slides with a strong degree of translation but often exhibiting non-circular rotational elements as well. Instability in the lower slopes has often led to cambering and valley bulging so that the slopes become deformed and slump earth flows developed at some sites. Several different types of landslide are examined in detail and by means of pollen analysis the slides are dated from the early postglacial to at least as recently as two thousand years B.P. although it has not yet been possible to decide when these slides started. The causes of sliding are identified, and comments are made upon.

• (a) The location of slip surfaces–which are frequently at the base of the Grindslow Shales above a sandstone aquifer.
• (b) The geomorphic processes which built up high pore-water pressures and steep pressure gradients in the past.
• (c) The effects of sliding on the development of hillslopes in the post-glacial period.

     

Remote sensing for landscape parameters and scale effect

Journal of the Indian Society of Remote Sensing - Development activities must be compatible for possibilities and limitation of natural environment and resources. Predevelopmental analysis must...     

Developing a large‐scale water‐balance approach to seasonal forecasting: application to the 2012 drought in Britain

Seasonal hydrological forecasts, or outlooks, can potentially provide water managers with estimates of river flows and water resources for a lead time of several months ahead. An experimental modelling tool for national hydrological outlooks has been developed which combines a hydrological model estimate of sub‐surface water storage across Britain with a range of seasonal rainfall forecasts to provide estimates of area‐wide hydrological conditions up to a few months ahead. The link is made between a deficit in sub‐surface water storage and a requirement for additional rainfall over subsequent months to enable sub‐surface water storage and river flow to return to mean monthly values. The new scheme is assessed over a recent period which includes the termination of the drought that affected much of Britain in the first few months of 2012. An illustration is provided of its use to obtain return‐period estimates of the ‘rainfall required’ to ease drought conditions; these are well in excess of 200 years for several regions of the country, for termination within a month of 1 April 2012, and still exceed 40 years for termination within three months. National maps of sub‐surface water storage anomaly show for the first time the current spatial variability of drought severity. They can also be used to provide an indication of how a drought situation might develop in the next few months given a range of possible future rainfall scenarios. © 2013 CEH/Crown and John Wiley & Sons, Ltd.     

Discard mitigation - what we can learn from waste minimization practices in other natural resources?

Solutions to the problem of discarding in fisheries have been debated for decades. Despite this attention, measures to ameliorate discarding have had limited success. Regulators, researchers, and industry continue to struggle with fisheries management and foregone yield in the face of the continued wastage of valuable resources due to discarding.Waste minimization and by-product utilization are powerful imperatives in other sectors that are also reliant on the harvest of natural resources. This paper considers the performance of these sectors in waste minimization and by-product utilization, with the aim of identifying practices and processes that may be applied to ameliorate discarding in fisheries.This paper describes the handling, utilization, and mitigation of discards and waste in the livestock farming, agriculture, mining, and waste management industries, and in particular, in forestry. In terms of biological impact, economic objectives, and management approaches the harvesting of trees has substantial similarities to industrialized fishing. However, the forestry sector has found ways to utilize almost 100% of the natural product harvest by establishing markets and new products. Analogous developments within the fishing industry could substantially improve sustainability through reduced levels of discarding and wastage. Based on the experiences of these sectors it is suggested that evaluations of potential Management Strategies are developed to specifically examine discard mitigation approaches on a broader scale than previously conducted.     

Der Tagesgang von Temperatur und Luftfeuchtigkeit in San Salvador

Zusammenfassung Der Tagesgang von Temperatur und Luftfeuchtigkeit in San Salvador zeigt deutliche jahreszeitliche Verschiedenheiten, die wesentlich durch Strahlungsgenuss, Sonnenauf- und Untergangszeiten und ein tageszeitliches mittelräumiges Windsystem bestimmt ist.

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Summary The daily variation of air temperature and humidity shows clear seasonal differences, which are essentially determined by incoming radiation, sunrise and sunset and a diurnal meso-scale wind system.

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Resumen El transcurso diurno de la temperatura y de la humedad del ambiente en San Salvador demuestra netamente diferencias segun la estación del año, las cuales se deben a las condiciones de radiación, salida y puesta del sol y un sistema diurno de viento.

     

Using impacts of deep-level mining to research karst hydrology—a Darcy-based approach to predict the future of dried-up dolomitic springs in the Far West Rand goldfield (South Africa). Part 2: predicting inter-compartmental flow and final groundwater tables

Some of the world’s deepest goldmines operate below dolomitic karst aquifers in the Far West Rand (FWR) goldfield, South Africa. Associated impacts include the continuous dewatering of karst aquifers for over six decades and irreversible changes of the hydrogeological setting. Affecting an area of approximately 400 km² by drawing down the water table up to 700 m, these impacts, and the large amounts of data generated in the process, are used as unique research opportunities to better understand the complex karst hydrology. The focus of this study is on predicting final water table elevations in rewatered aquifers after mining ceases taking the fact that mines hydraulically linked previously disconnected aquifers into account. While part 1 of this series develops the conceptual model, this second part utilises large sets of pertinent data to calculate actual flow rates for predicting the fate of dried up springs after mine closure. Following a Darcy-based approach first applied by Swart et al. (Environ Geol 44:751–770, 2003a) it is not only predicted that the springs will flow again but also shown that linear relationships exist between flow rates through a combined system of karst-fractured aquifers overlying the mine void and the associated hydraulic head driving them. This suggests that—at this scale—porous media-based equations can be meaningfully used to predict flow in non-porous media.     

Ionospheric Scintillation and Dynamics of Fresnel-Scale Irregularities in the Inner Region of the Equatorial Ionization Anomaly

This paper reports differences in the occurrence statistics of global positioning system (GPS) L-band scintillations at observational sites located in the inner regions of the northern and southern crests of the equatorial ionization anomaly. Ground-based GPS data acquired at the closed magnetically aligned stations of Manaus (3.1°S; 59.9°W; dip lat. 6.2°N) and Cuiabá (15.5°S; 56.1°W; dip. lat. 6.2°S), Brazil, from December 2001 to February 2007 are used in the analysis. The drift dynamics of Fresnel-scale ionospheric irregularities at the southern station of Cuiabá are also investigated. Only geomagnetically quiet days with the sum of daily Kp < 24 were used in the analysis statistics and in the irregularity drift studies. The results reveal a clear dependence of the scintillation occurrence with the solar activity, but there exists an asymmetry in the percentage of scintillation occurrence between the two stations throughout the period analyzed. The nocturnal occurrence of the scintillations over Cuiabá is predominantly larger than over Manaus, but this scenario seems to change with the decline in the solar activity (mainly during local post-midnight hours). A broad minimum and maximum in the scintillation occurrence appears to occur over both the stations, respectively, during the June solstice (winter) and December solstice (summer) months. The dynamics of the Fresnel-scale irregularities, as investigated from the estimations of the mean zonal drift velocities, reveals that the amplitude of the eastward drifts tends to reduce with the decline in the solar activity. The magnitude of the zonal drift velocities during the December solstice months is larger than during the equinoxes, with the differences being more pronounced at solar maximum years. Other relevant aspects of the observations, with complementary data from a low-latitude ionospheric model, are highlighted and discussed.