title: Interhemispheric gradient of atmospheric radiocarbon reveals natural variability of Southern Ocean winds

authors: Rodgers, K.B.

subjects: Δ¹⁴C

abstract: Tree ring Δ¹⁴C data (Reimer et al., 2004; McCormac et al., 2004) indicate that atmospheric Δ¹⁴C varied on multi-decadal to centennial timescales, in both hemispheres, over the pre-industrial period AD 950–1830. Although the Northern and Southern Hemispheric Δ¹⁴C records display similar variability, it is difficult from these data alone to distinguish between variations driven by ¹⁴CO₂ production in the upper atmosphere (Stuiver, 1980) and exchanges between carbon reservoirs (Siegenthaler, 1980). Here we consider rather the Interhemispheric Gradient in atmospheric Δ¹⁴C as revealing of the background pre-bomb air-sea Disequilbrium Flux between 14CO₂ and CO₂. As the global maximum of the Disequilibrium Flux is squarely centered in the open ocean regions of the Southern Ocean, relatively modest perturbations to the winds over this region drive significant perturbations to the Interhemispheric Gradient. The analysis presented here implies that changes to Southern Ocean windspeeds are likely a main driver of the observed variability in the Interhemispheric Gradient over 950–1830, and further, that this variability may be larger than the Southern Ocean wind trends that have been reported for recent decades (notably 1980–2004). This interpretation also implies a significant weakening of the winds over the Southern Ocean within a few decades of AD 1375, associated with the transition between the Medieval Climate Anomaly and the Little Ice Age. The driving forces that could have produced such a shift in the winds remain unkown.

text: Interhemispheric gradient of atmospheric radiocarbon reveals natural variability of Southern Ocean winds Tree ring Δ¹⁴C data (Reimer et al., 2004; McCormac et al., 2004) indicate that atmospheric Δ¹⁴C varied on multi-decadal to centennial timescales, in both hemispheres, over the pre-industrial period AD 950–1830. Although the Northern and Southern Hemispheric Δ¹⁴C records display similar variability, it is difficult from these data alone to distinguish between variations driven by ¹⁴CO₂ production in the upper atmosphere (Stuiver, 1980) and exchanges between carbon reservoirs (Siegenthaler, 1980). Here we consider rather the Interhemispheric Gradient in atmospheric Δ¹⁴C as revealing of the background pre-bomb air-sea Disequilbrium Flux between 14CO₂ and CO₂. As the global maximum of the Disequilibrium Flux is squarely centered in the open ocean regions of the Southern Ocean, relatively modest perturbations to the winds over this region drive significant perturbations to the Interhemispheric Gradient. The analysis presented here implies that changes to Southern Ocean windspeeds are likely a main driver of the observed variability in the Interhemispheric Gradient over 950–1830, and further, that this variability may be larger than the Southern Ocean wind trends that have been reported for recent decades (notably 1980–2004). This interpretation also implies a significant weakening of the winds over the Southern Ocean within a few decades of AD 1375, associated with the transition between the Medieval Climate Anomaly and the Little Ice Age. The driving forces that could have produced such a shift in the winds remain unkown.

year: 2011

title: Sustaining effective literacy practices over time in secondary schools: School organisational and change issues

authors: May, Stephen

subjects: literacy

abstract: The effective, sustained implementation of literacy across the curriculum in secondary schools is still a relatively rare phenomenon. This is because such an approach to literacy requires secondary schools to undergo extensive and complex processes of school change, involving altering teachers’ thinking, attitudes and behaviour in relation to literacy and pedagogy, and establishing andmaintaining organisational processes that support teachers’ change processes and their impact on student learning. Such changes take time, not least because they often run counter to traditional organisational and pedagogical approaches in secondary schools. Drawing on our research evaluation of the Secondary  Schools’ Literacy Initiative (SSLI) in New Zealand, this paper examines the medium to long term implications of school change processes for secondary schools undertaking a cross-curricular literacy focus. In so doing, it identifies three key phases that secondary schools may undergo in order to achieve and sustain effective literacy practices over time and suggests that these phases, and their characteristics, may well have wider applicability.

text: Sustaining effective literacy practices over time in secondary schools: School organisational and change issues The effective, sustained implementation of literacy across the curriculum in secondary schools is still a relatively rare phenomenon. This is because such an approach to literacy requires secondary schools to undergo extensive and complex processes of school change, involving altering teachers’ thinking, attitudes and behaviour in relation to literacy and pedagogy, and establishing andmaintaining organisational processes that support teachers’ change processes and their impact on student learning. Such changes take time, not least because they often run counter to traditional organisational and pedagogical approaches in secondary schools. Drawing on our research evaluation of the Secondary  Schools’ Literacy Initiative (SSLI) in New Zealand, this paper examines the medium to long term implications of school change processes for secondary schools undertaking a cross-curricular literacy focus. In so doing, it identifies three key phases that secondary schools may undergo in order to achieve and sustain effective literacy practices over time and suggests that these phases, and their characteristics, may well have wider applicability.

year: 2007

title: Photography within te ao Māori: Decolonising the photographic lens

authors: Hill, Rodrigo

abstract: Ūkaipō: Wānanga, places of origin and photographic representation. 
Ūkaipō recognises the cultural, emotional, and spiritual along with the physical ties a Māori has with their place of origin, even if it is not their place of birth, emphasising grounded forms of connection between people and place and subsequent understandings of places and spaces.  Hence the importance today of people asserting their pēpeha, tohu whenua landmarks with which they most strongly identify, consolidating their ‘birth of place’ or ‘place of birth’.

text: Photography within te ao Māori: Decolonising the photographic lens Ūkaipō: Wānanga, places of origin and photographic representation. 
Ūkaipō recognises the cultural, emotional, and spiritual along with the physical ties a Māori has with their place of origin, even if it is not their place of birth, emphasising grounded forms of connection between people and place and subsequent understandings of places and spaces.  Hence the importance today of people asserting their pēpeha, tohu whenua landmarks with which they most strongly identify, consolidating their ‘birth of place’ or ‘place of birth’.

year: 2024