Natural self-cleaning of oil-polluted beaches by waves

Changes in the magnitude of oil pollution on five prototype study beaches on Israel's northern Mediterranean coast had been monitored at 2- to 4-weekly intervals from 21 November 1980 to 19 March 1981. Statistical analyses of these changes were employed to rank the beaches in order of decreasing self-cleaning capacity. Records of storm-induced wave data records for the winter of 1980–1981 were correlated to incidence of change in the magnitude of subsurface tarball pollution and the rate of emplaced fuel sample dissipation on the study beaches. Specific wave breaking processes, overtopping of offshore obstacles and wave refraction were singled out as accelerating or retarding wave energy transfer to the polluted beaches. Attribution of the occurrence of specific local littoral processes to observed change in beach pollution magnitude made it possible to assess potential oil spill damage. Elucidation of the causative processes provided theoretical corroboration for beach sensitivity ranking established earlier by statistical analysis.     

Astrodynamical Space Test of Relativity using Optical Devices I (ASTROD I)—a class-M fundamental physics mission proposal for cosmic vision 2015–2025: 2010 Update

ASTROD I is a planned interplanetary space mission with multiple goals. The primary aims are: to test General Relativity with an improvement in sensitivity of over 3 orders of magnitude, improving our understanding of gravity and aiding the development of a new quantum gravity theory; to measure key solar system parameters with increased accuracy, advancing solar physics and our knowledge of the solar system; and to measure the time rate of change of the gravitational constant with an order of magnitude improvement and the anomalous Pioneer acceleration, thereby probing dark matter and dark energy gravitationally. It is envisaged as the first in a series of ASTROD missions. ASTROD I will consist of one spacecraft carrying a telescope, four lasers, two event timers and a clock. Two-way, two-wavelength laser pulse ranging will be used between the spacecraft in a solar orbit and deep space laser stations on Earth, to achieve the ASTROD I goals.For this mission, accurate pulse timing with an ultra-stable clock, and a drag-free spacecraft with reliable inertial sensor are required. T2L2 has demonstrated the required accurate pulse timing; rubidium clock on board Galileo has mostly demonstrated the required clock stability; the accelerometer on board GOCE has paved the way for achieving the reliable inertial sensor; the demonstration of LISA Pathfinder will provide an excellent platform for the implementation of the ASTROD I drag-free spacecraft. These European activities comprise the pillars for building up the mission and make the technologies needed ready. A second mission, ASTROD or ASTROD-GW (depending on the results of ASTROD I), is envisaged as a three-spacecraft mission which, in the case of ASTROD, would test General Relativity to one part per billion, enable detection of solar g-modes, measure the solar Lense-Thirring effect to 10 parts per million, and probe gravitational waves at frequencies below the LISA bandwidth, or in the case of ASTROD-GW, would be dedicated to probe gravitational waves at frequencies below the LISA bandwidth to 100?nHz and to detect solar g-mode oscillations. In the third phase (Super-ASTROD), larger orbits could be implemented to map the outer solar system and to probe primordial gravitational-waves at frequencies below the ASTROD bandwidth. This paper on ASTROD I is based on our 2010 proposal submitted for the ESA call for class-M mission proposals, and is a sequel and an update to our previous paper (Appouchaux et al., Exp Astron 23:491?C527, 2009; designated as Paper I) which was based on our last proposal submitted for the 2007 ESA call. In this paper, we present our orbit selection with one Venus swing-by together with orbit simulation. In Paper I, our orbit choice is with two Venus swing-bys. The present choice takes shorter time (about 250?days) to reach the opposite side of the Sun. We also present a preliminary design of the optical bench, and elaborate on the solar physics goals with the radiation monitor payload. We discuss telescope size, trade-offs of drag-free sensitivities, thermal issues and present an outlook.     

Urban settlement program and land dispute resolution: The State of Israel versus the Negev Bedouin

Geo-political changes and the drive to higher standards of living induce growing numbers of nomad populations to give-up their special way of life. The Bedouin of the Israeli Negev are no exception. Gradually, they settled down in scattered, unauthorized clusters of tents and shacks in the open lands of the northern Negev. Governments of Israel were unsatisfied with the emerging unplanned spontaneous settlements. Consequently, governmental planning agencies came up with a program to house the Bedouin population in seven new towns. The government's initiative in establishing the towns had two main objectives. First, urban settlements were viewed as conduits for the provision of modern utilities and social services that were very hard to supply and distribute among the many small and scattered spontaneous settlements. Second, Bedouin put forward claims over much of the lands they arguably were using in their former way of life as nomads. Although the claims were not – and could not be – supported by legal documents, the government offered the Bedouin subsidized developed urban land in exchange of their claims over the undeveloped dry desert lands. Currently, more than 60 per cent of the Negev Bedouin population reside in the seven planned urban settlements. Nevertheless, only a small proportion of the land claims has been settled. This paper argues that the attempt to achieve both goals via the urban settlement program was too ambitious. While the goal of providing better services in urban areas has been partially accomplished, the goal of removing the claims over the lands is far from being resolved. The paper argues that the link between the two goals should be reconsidered. This revised version was published online in July 2006 with corrections to the Cover Date.     

The effect of magnetite particle size on paleointensity determinations of the geomagnetic field

The Thellier method for paleointensity determinations has been applied to prepared samples containing magnetites whose mean particle sizes range from single domain, SD, to multidomain, MD. Linear (ideal) PNRM-PTRM curves are obtained for samples containing SD and submicron magnetite particles. However, for MD particles non-linear (concave-up) PNRM-PTRM curves are observed such that a linear approximation to the lower blocking-temperature data leads to apparent paleointensities that are higher than the actual paleofield; however, the ratio of the end-points, NRM/TRM, yields the correct (laboratory) intensity. The non-linear (concave-up) PNRM-PTRM curves for the MD particles are explained in terms of the lack of symmetry of the domain-wall movements during the two heatings of the Thellier experiment. Low stabilities with respect to alternating fields and with respect to temperature cycles below magnetite's isotropic temperature are diagnostic in detecting samples most likely to exhibit non-linearities due to the MD effect.