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Creators/Authors contains: "Guthrie, John"

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  1. Understanding and predicting Arctic change and its impacts on global climate requires broad, sustained observations of the atmosphere-ice-ocean system, yet technological and logistical challenges severely restrict the temporal and spatial scope of observing efforts. Satellite remote sensing provides unprecedented, pan-Arctic measurements of the surface, but complementary in situ observations are required to complete the picture. Over the past few decades, a diverse range of autonomous platforms have been developed to make broad, sustained observations of the ice-free ocean, often with near-real-time data delivery. Though these technologies are well suited to the difficult environmental conditions and remote logistics that complicate Arctic observing, they face a suite of additional challenges, such as limited access to satellite services that make geolocation and communication possible. This paper reviews new platform and sensor developments, adaptations of mature technologies, and approaches for their use, placed within the framework of Arctic Ocean observing needs. 
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  2. null (Ed.)
    Abstract Arctic Ocean surface circulation change should not be viewed as the strength of the anticyclonic Beaufort Gyre. While the Beaufort Gyre is a dominant feature of average Arctic Ocean surface circulation, empirical orthogonal function analysis of dynamic height (1950–89) and satellite altimetry–derived dynamic ocean topography (2004–19) show the primary pattern of variability in its cyclonic mode is dominated by a depression of the sea surface and cyclonic surface circulation on the Russian side of the Arctic Ocean. Changes in surface circulation after Arctic Oscillation (AO) maxima in 1989 and 2007–08 and after an AO minimum in 2010 indicate the cyclonic mode is forced by the AO with a lag of about 1 year. Associated with a one standard deviation increase in the average AO starting in the early 1990s, Arctic Ocean surface circulation underwent a cyclonic shift evidenced by increased spatial-average vorticity. Under increased AO, the cyclonic mode complex also includes increased export of sea ice and near-surface freshwater, a changed path of Eurasian runoff, a freshened Beaufort Sea, and weakened cold halocline layer that insulates sea ice from Atlantic water heat, an impact compounded by increased Atlantic Water inflow and cyclonic circulation at depth. The cyclonic mode’s connection with the AO is important because the AO is a major global scale climate index predicted to increase with global warming. Given the present bias in concentration of in situ measurements in the Beaufort Gyre and Transpolar Drift, a coordinated effort should be made to better observe the cyclonic mode. 
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  3. Interventions can enhance students' motivation for reading, but few researchers have assessed the effects of the specific motivation‐enhancing practices that comprise these interventions. Even fewer have evaluated how students' perceptions of different intervention practices impact their later motivation and academic outcomes. In this study, we utilised data from a study of Concept‐Oriented Reading Instruction, a programme designed to enhance seventh‐grade students' reading comprehension and motivation. We examined the effects of students perceiving one practice from this intervention, emphasising the importance of reading, which was designed to enhance their task values for reading (Eccles‐Parsons et al.,). Unexpectedly, structural equation modelling analyses showed that students' perceptions of importance support predicted their later competence‐related beliefs, but not their task values. Students' competence‐related beliefs predicted their reading comprehension and behavioural engagement, whereas students' task values predicted reading engagement. However, there were no significant indirect effects of perceiving importance support on students' reading outcomes. 
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