Drake-Scotia Sea gateways: onset and evolution of the Drake Passage and Scotia Sea, implications for global ocean circulation and climate

Australasian IODP Regional Planing Workshop (2017. Sidney)Instituto Geológico y Minero de España, EspañaInstituto Andaluz de Ciencias de la Tierra, Consejo Superior de Investigaciones Científicas, EspañaIstituto Nazionale di Oceanografia e Geofisica Sperimentale, ItaliaSan Diego State University, Estados UnidosPeer reviewe

Onset and development of the Drake Passage and Scotia Sea gateways and its influence on global ocean circulation and climate (IODP proposal)

The DRAKE-SCOTIA SEA GATEWAYS is a new multidisciplinary International Ocean Discovery Program (IODP) drilling proposal aimed at determining the time of opening and pattern of development of gateways in the Drake Passage and the adjacent Scotia Sea, and their influence on global ocean circulation, biotic evolution and climate. The Drake Passage with the adjacent Scotia Sea represent one of Earth’s most important oceanic gateways, between the southern tip of South America and the Antarctic Peninsula, a crucial area for water mass exchange between the Pacific Ocean, the Atlantic Ocean and the Weddell Sea, the importance of which is evidence by in many multinational studies. Nevertheless, the region has not been yet drilled for scientific purposes. The objective of this work is to present the main scientific goals of this drilling proposal and its link with the IODP Science Plan for 2013-2023.Department of Earth Sciences, Royal Holloway University, Reino UnidoBritish Antarctic Survey, Reino UnidoDepartment og Geology and Geophysics, Yale University, Estados UnidosGeophysical Department, Geological Survey of Denmark and Greenland, DinamarcaAlfred Wegener Institute, Helmholtz for Polar and Marine Research, AlemaniaInstituto Geológico y Minero de España, EspañaOcean and Earth Science, University of Southampton, Reino UnidoUniversity Texas at Austin, Estados UnidosInstitute of Petroleum Engineering, Heriot-Watt University, Reino UnidoInstituto Andaluz de Ciencias de la Tierra, Consejo Superior de Investigaciones Científicas, EspañaInstituto Andaluz de Ciencias de la Tierra, Universidad de Granada, EspañaCollege of Earth, Ocean and the Environment, University of Delaware, Estados UnidosUniversity New South Wales, AustraliaUniversity Nebraska-Lincoln, Estados UnidosUniversidad de Buenos Aires, Argentin

Applications of electrified dust and dust devil electrodynamics to Martian atmospheric electricity

Atmospheric transport and suspension of dust frequently brings electrification, which may be substantial. Electric fields of 10 kVm-1 to 100 kVm-1 have been observed at the surface beneath suspended dust in the terrestrial atmosphere, and some electrification has been observed to persist in dust at levels to 5 km, as well as in volcanic plumes. The interaction between individual particles which causes the electrification is incompletely understood, and multiple processes are thought to be acting. A variation in particle charge with particle size, and the effect of gravitational separation explains to, some extent, the charge structures observed in terrestrial dust storms. More extensive flow-based modelling demonstrates that bulk electric fields in excess of 10 kV m-1 can be obtained rapidly (in less than 10 s) from rotating dust systems (dust devils) and that terrestrial breakdown fields can be obtained. Modelled profiles of electrical conductivity in the Martian atmosphere suggest the possibility of dust electrification, and dust devils have been suggested as a mechanism of charge separation able to maintain current flow between one region of the atmosphere and another, through a global circuit. Fundamental new understanding of Martian atmospheric electricity will result from the ExoMars mission, which carries the DREAMS (Dust characterization, Risk Assessment, and Environment Analyser on the Martian Surface)-MicroARES (Atmospheric Radiation and Electricity Sensor) instrumentation to Mars in 2016 for the first in situ measurements

Assessment of automated multitemporal image co-registration using repeat station imaging techniques

Repeat station imaging (RSI) is a method for specialized image collection and co-registration that facilitates rapid change detection with aerial imagery for time-critical analyses. Our previously reported research has defined methods for automated multitemporal image co-registration and demonstrated the utility of RSI for achieving precise co-registration, but without actually automating the technique. For this paper, we developed a custom software implementing specific procedures for automated RSI-based image co-registration, processed 252 image pairs containing diverse scenes and collection conditions, and evaluated the performance of RSI and the auto-registration tool. We found that the average root-mean-square error of image co-registration ranged between 1.3 and 1.9 pixels for aerial RSI images with 8–14 cm spatial resolution captured at the same time of day. The implications of these findings are that automated multitemporal co-registration and automated change detection could be performed in near real-time onboard an aircraft as it flies, opening up a range of new monitoring applications, particularly with unmanned aircraft systems. However, results with our custom software also indicate that images captured at different times of day with varying illumination and shadow conditions yield poor co-registration, and in some instances fail to register