Salinity changes in the world ocean since 1950 in relation to changing surface freshwater fluxes

Global hydrographic and air–sea freshwater flux datasets are used to investigate ocean salinity changes over 1950–2010 in relation to surface freshwater flux. On multi-decadal timescales, surface salinity increases (decreases) in evaporation (precipitation) dominated regions, the Atlantic–Pacific salinity contrast increases, and the upper thermocline salinity maximum increases while the salinity minimum of intermediate waters decreases. Potential trends in E–P are examined for 1950–2010 (using two reanalyses) and 1979–2010 (using four reanalyses and two blended products). Large differences in the 1950–2010 E–P trend patterns are evident in several regions, particularly the North Atlantic. For 1979–2010 some coherency in the spatial change patterns is evident but there is still a large spread in trend magnitude and sign between the six E–P products. However, a robust pattern of increased E–P in the southern hemisphere subtropical gyres is seen in all products. There is also some evidence in the tropical Pacific for a link between the spatial change patterns of salinity and E–P associated with ENSO. The water cycle amplification rate over specific regions is subsequently inferred from the observed 3-D salinity change field using a salt conservation equation in variable isopycnal volumes, implicitly accounting for the migration of isopycnal surfaces. Inferred global changes of E–P over 1950–2010 amount to an increase of 1 ± 0.6 % in net evaporation across the subtropics and an increase of 4.2 ± 2 % in net precipitation across subpolar latitudes. Amplification rates are approximately doubled over 1979–2010, consistent with accelerated broad-scale warming but also coincident with much improved salinity sampling over the latter period.

World soybean trade : growth and sustainability

Soybeans can be consumed directly as food, and in China hey are the major ingredient in food products such as tofu and soy milk, but direct consumption is small relative to their wider use in animal feed, and it is the requirement for livestock feed that drives international trade. Rapid growth of economies and population, especially in Asia, has led to increased demand for animal protein and cooking oil. This paper analyses the recent growth in supply of soybeans from North and South America to China, and considers the factors that may affect this trade in future; a contrast is made with supply from North and South America to Europe, which has not been increasing. The constraints preventing an increase in supply of soybeans to Europe are reviewed. The paper concludes with brief discussion of the factors which will affect world markets for soybeans and soybean products in future.

Hollywood in the world market – evidence from Australia in the mid-1930s

By the mid-1930s the major Hollywood studios had developed extensive networks of distribution subsidiaries across five continents. This article focuses on the operation of American film distributors in Australia – one of Hollywood's largest foreign markets. Drawing on two unique primary datasets, the article compares and investigates film distribution in Sydney's first-run and suburban-run markets. It finds that the subsidiaries of US film companies faced a greater liability of foreignness in the city centre market than in the suburban one. Our data support the argument that film audiences in local or suburban cinema markets were more receptive to Hollywood entertainment than those in metropolitan centres.

iPad use in fieldwork: formal and informal use to enhance pedagogical practice in a bring your own technology world

We report on use of iPads (and other IOS devices) for student fieldwork use and as electronic field notebooks and to promote active. We have used questionnaires and interviews of tutors and students to elicit their views and technology and iPad use for fieldwork. There is some reluctance for academic staff to relinquish paper notebooks for iPad use, whether in the classroom or on fieldwork, as well as use them for observational and measurement purposes. Students too are largely unaware of the potential of iPads for enhancing fieldwork. Apps can be configured for a wide variety of specific uses that make iPads useful for educational as well as social uses. Such abilities should be used to enhance existing practice as well as make new functionality. For example, for disabled students who find it difficult to use conventional note taking. iPads can be used to develop student self-directed learning and for group contributions. The technology becomes part of the students’ personal learning environments as well as at the heart of their knowledge spaces – academic and social. This blurring of boundaries is due to iPads’ usability to cultivate field use, instruction, assessment and feedback processes. iPads can become field microscopes and entries to citizen science and we see the iPad as the main ‘computing’ device for students in the near future. As part of the Bring Your Own Technology/Device (BYOD) the iPad has much to offer although, both staff and students need to be guided in the most effective use for self-directed education via development of Personal Learning Environments. A more student-oriented pedagogy is suggested to correspond to the increasing use of tablet technologies by students