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The space hurricane is a large‐scale three‐dimensional magnetic vortex structure that can cause massive local energy injections in the polar cap. By analyzing Defense Meteorological Satellite Program (DMSP) F16–F19 satellite observations from 2005 to 2016, we found that the Southern Hemisphere space hurricane mainly occurs in summer under negative By dominated northward interplanetary magnetic field (IMF) conditions. In particular, the space hurricanes are more likely to occur in the dayside polar cap at magnetic latitude greater than 80°. The characteristics for the Southern Hemisphere are basically consistent with the characteristics of space hurricanes in the Northern Hemisphere. The different dependences of By component in different hemispheres supports the high‐latitude lobe reconnection as the formation mechanism. Plasma data from DMSP satellites in both hemispheres show that the appearance of the space hurricane greatly enhances the convection in the polar cap and the electron density on its dawn side. Within the space hurricane, electron temperatures typically increase significantly, accompanied by strong upward field‐aligned currents and electron precipitation. These results give us a better understanding of the solar wind‐magnetosphere‐polar ionosphere coupling process under northward IMF conditions. Plain Language Summary: The space hurricane is defined as a large three‐dimensional magnetic vortex structure that spans the polar ionosphere and magnetosphere. Previous research has pointed out that it often appears as an aurora spot near the north magnetic pole, which can greatly enhance the convection patterns and current systems in the polar ionosphere. To clarify its occurrence rate and characteristics in the Southern Hemisphere, we identified the 259 space hurricane events from the long‐term DMSP satellite observations in the Southern Hemisphere. The statistical results indicated that the Southern Hemisphere space hurricanes mainly occur in summer and dayside polar cap under negative By dominated and northward IMF conditions. In addition, we found that the electron temperatures within the space hurricane increased significantly and accompanied by strong upward field‐aligned field currents and electron precipitation. The appearance of the space hurricane greatly enhances the plasma velocity and the electron density on its dawn side. The characteristics in the Southern Hemisphere are basically consistent with the characteristics of space hurricanes in the Northern Hemisphere, and support high‐latitude lobe reconnection as the formation mechanism. This work helps us understand the spatial and temporal characteristics of the space hurricane and their impact on plasma parameters. Key Points: Space hurricanes in the Southern Hemisphere mainly occur in summer and afternoon sector with negative By dominated northward IMFPlasma data from DMSP satellites indicate that the space hurricane has enhanced Te, horizontal convection and Ne on its dawn sideStatistical properties of space hurricanes in the Southern Hemisphere are consistent with high‐latitude lobe reconnection [ABSTRACT FROM AUTHOR]

Long-term change in the height of the ionospheric F2 layer, hmF 2, is predicted to result from increased levels of tropospheric greenhouse gases. Sufficiently long sequences of ionospheric data exist to investigate this long-term change, recorded by a global network of ionosondes. However, direct measurements of ionospheric layer height with these instruments is not possible. As a result, most estimates of hmF 2 rely on empirical formulae based on parameters routinely scaled from ionograms. Estimates of trends in hmF 2 using these formulae show no global consensus. We present an analysis in which data from the Japanese ionosonde station at Kokubunji were used to estimate monthly median values of hmF 2 using an empirical formula. These were then compared with direct measurements of the F2 layer height determined from Incoherent Scatter measurements made at the Shigaraki MU observatory, Japan. Our results reveal that the formula introduces diurnal, seasonal and long-term biases in the estimates of hmF 2 of ≈ ±10 % (±25 km an altitude of 250 km). These can be explained by the presence of underlying F 1 layer ionisation not accounted for in the formula. We demonstrate, that for Kokobunji, the ratio of F2/F1 peak electron concentrations is strongly controlled by changes in geomagnetic activity represented by the am index. Changes in thermospheric composition in response to geomagnetic activity have been shown to be highly localised. We conclude that localised changes in thermospheric composition modulate the F2/F1 peak ratio, leading to differences in hmF 2 trends. We further conclude that the influence of thermospheric composition on the underlying ionosphere needs to be accounted for in these empirical formulae if they are to be applied to studies of long-term ionospheric change. [ABSTRACT FROM AUTHOR]

This article looks at how four British-based poets born in the Caribbean exploit the rich language repertoire available to them in their work for children and young people. Following initial consideration of questions of definition and terminology, poetry collections by James Berry, John Agard, Grace Nichols and Valerie Bloom are discussed, with a focus on the interplay and creative tension between the different varieties of Caribbean creoles ("Bad Talk") and standard English evident in their work. Variation both between the four poets' usage and within each individual poet's work is considered, and a trend over time towards the inclusion of fewer creole-influenced poems is noted. These and other issues, such as the labelling of the four poets' work as "performance poetry" and the nature of the poets' contribution to British children's literature, are considered in the conclusion.

This paper reports the findings of a small-scale research project which investigated the levels of awareness and knowledge of written standard English of 10 and 11-year-old children in two English primary schools. The project involved repeating in 2010 a written questionnaire previously used with children in the same schools in three separate surveys in 1999, 2002 and 2005. Data from the latest survey are compared to those from the previous three. The analysis seeks to identify any changes over time in children's ability to recognise non-standard forms and supply standard English alternatives, as well as their ability to use technical terms related to language variation. Differences between the performance of boys and girls and that of the two schools are also analysed. The paper concludes that the socio-economic context of the schools may be a more important factor than gender in variations over time identified in the data.

This article looks at how Ted Hughes' poetry for children developed over more than 30 years of publication. It traces the movement from his earlier, more conventional rhyming poems, such as "Meet My Folks!" (1961) and "Nessie the Mannerless Monster" (1964), to the mature, free verse "animal poems" for older readers of "Season Songs" (1976c), "Under the North Star" (1981) and the "farmyard fable" "What Is the Truth?" (1984). The article argues that the later lyrical poems for younger readers where Hughes returned to rhyme, "The Cat and the Cuckoo" (1987) and "The Mermaid's Purse" (1993), represent an undervalued final phase of Hughes' work for children which is rarely discussed by critics. The discussion considers Hughes' changing attitude to the concept of the "children's poet" at different periods of his career. Reference is made throughout to Hughes' own writing about children and poetry, such as "Poetry in the Making" (1967), and to parallel developments in his poetry for adults.