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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2005.09.004 Byline: Toshihiro Sakamoto (a), Isao Umetsu (a)(b) Abstract: We investigate how the bottom slope affects the time-dependent global energy balance of a two-layer subtropical gyre driven by seasonal winds in order to reformulate the concept joint effect of baroclinicity and bottom relief (JEBAR) based on energetics rather than vorticity dynamics. It is shown that the role of JEBAR in this situation is to transfer energy between the barotropic and baroclinic fields. Since a deep current tends to flow in meridional directions along a meridional ridge, the geostrophically balanced pressure-gradient forces can perform work on the zonal barotropic flow over the ridge. The direction of the deep motion, and hence the sign of the work is reversed seasonally because the pressure field in the lower layer exhibits an anticyclonic tendency in winter and a cyclonic tendency in summer. The topographic beta effect strengthens the work on the northwest and southeast sides of the ridge, so that the net contribution from the ridge region is negative in winter and positive in summer. On the other hand, this work must be canceled by enhancing the energy conversion to satisfy the energy equation. As a result, the ridge not only accelerates but also seasonally reverses the sign of the rate of energy conversion. With some modification, a meridional trench and a western continental slope turn out to have qualitatively the same effect on the seasonal transport variation. Therefore, the annual range in the barotropic transport of the gyre is, to varying degrees, reduced irrespective of the details of the large-scale bottom topography. Author Affiliation: (a) Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan (b) Naval Systems Department, Radio Application Division, Aerospace and Defense Operations Unit, NEC Corporation, Fuchu, Tokyo 183-8501, Japan Article History: Received 17 February 2005; Revised 12 September 2005; Accepted 24 September 2005

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.techfore.2009.06.010 Byline: Greg Tegart Keywords: Nanotechnologies; Energy futures; Energy conversion; Energy storage; Energy use Abstract: This paper explores the possibilities offered by the use of nanotechnologies to contribute to new and improved approaches to energy conversion, storage and distribution in Australia in the short term (less than 5 years), medium term (5-15 years) and long term (greater than 15 years). In 2007 the Australian Academy of Technological Sciences and Engineering (ATSE) examined the potential for the application of nanotechnologies to future energy systems in Australia. Four workshops were held in major cities around Australia bringing ATSE Fellows and experts together for brainstorming sessions and a questionnaire was circulated more widely. These provided inputs on future energy needs in Australia and the critical areas to be considered in research and commercialisation of nanotechnologies in energy systems. Using a matrix approach a number of opportunities were identified as short term -- energy conservation, environmental management, catalysts for combustion, photovoltaic cells; medium term -- catalysts for conversion of biomass, gas and coal, fuel cells, advanced photovoltaics, capture and storage of carbon dioxide; and long term -- hydrogen production, storage and use. These applications are discussed in the Australian context. The implications for government policy on support of the findings are discussed. Author Affiliation: Centre for Strategic Economic Studies, Victoria University, City Flinders Campus, PO Box 14428, Melbourne, 8001, Australia Article History: Received 24 November 2008; Revised 4 June 2009; Accepted 10 June 2009