title: The Amplification of Tsunamis by Mercury Bay, New Zealand

authors: Ramli, Andi Yulianti

subjects: Tsunami

abstract: The east coast of New Zealand is exposed to tsunami hazards, which are generated by both distant and near tsunamigenic sources. The impact of tsunami varies along the coast depending on the source region and the amount of local attenuation or amplification. Some regions have consistently amplified historic tsunami, including Mercury Bay on the east coast of the Coromandel Peninsula. Whitianga, located in the Mercury Bay, is now the fastest growing population centre in the Coromandel Region; hence, tsunami hazard is of particular concern. The natural resonance periods (eigen periods) of Mercury Bay are determined by its geometry and depth, and tsunami waves that enter the Bay will be amplified when their frequencies match the resonant frequencies of the Bay. The combination of tide levels with the amplified tsunami waves may lead to a destruction of the moored vessels and many coastal facilities. To date, amplification within the bay has mostly increased the trough depth, while having little effect on the crest height.

This study assesses the tsunami hazard in Mercury Bay in response to a tsunami generated along the Kermadec subduction margin (Kermadec Trench). Even though historically, the Kermadec Trench has never produced a hazardous tsunami affecting the eastern coast of New Zealand, it is still important to develop an assessment of the worst scenarios of earthquake generated tsunamis from this source. In particular, the Sumatra 2004 and Tohuku 2011 tsunami events have suggested that a magnitude Mw 9 to 9.5 subduction megathrust earthquake is a plausible scenario.
Merian’s formula was used to obtain the natural resonant period of Mercury Bay and 17 scenarios of tsunamigenic earthquakes were simulated using the tsunami model COMCOT version 1.7. Those scenarios included the recent various combination of the Kermadec earthquake, and hypothetical earthquakes that rupture the northern, middle, southern parts of Kermadec Trench. The results demonstrate that most of the initial tsunami waves generated by Kermadec Trench earthquakes are negative waves that arrive in the Bay within 56 to 158 minutes of the earthquake. This may explain the observed historical pattern of enhanced amplification of the troughs. However, significant amplification of the crests, producing waves that would threaten Whitianga Township, are generated by Kermadec earthquakes with magnitudes greater than Mw 8.5.
From the spectral analysis of each tsunami model, Mercury Bay showed a consistent response of about 52 minutes dominant period. This period is also shown as the period of the Mercury Bay when tsunami is absent. In response to distant tsunamis, it seems that the geometry of the Mercury Bay control their periods as they enter the bay. Both the 2011 Tohoku and 2010 Chilean Events have the dominant periods close to the Mercury Bay period at 47 and 51 minutes respectively.

text: The Amplification of Tsunamis by Mercury Bay, New Zealand The east coast of New Zealand is exposed to tsunami hazards, which are generated by both distant and near tsunamigenic sources. The impact of tsunami varies along the coast depending on the source region and the amount of local attenuation or amplification. Some regions have consistently amplified historic tsunami, including Mercury Bay on the east coast of the Coromandel Peninsula. Whitianga, located in the Mercury Bay, is now the fastest growing population centre in the Coromandel Region; hence, tsunami hazard is of particular concern. The natural resonance periods (eigen periods) of Mercury Bay are determined by its geometry and depth, and tsunami waves that enter the Bay will be amplified when their frequencies match the resonant frequencies of the Bay. The combination of tide levels with the amplified tsunami waves may lead to a destruction of the moored vessels and many coastal facilities. To date, amplification within the bay has mostly increased the trough depth, while having little effect on the crest height.

This study assesses the tsunami hazard in Mercury Bay in response to a tsunami generated along the Kermadec subduction margin (Kermadec Trench). Even though historically, the Kermadec Trench has never produced a hazardous tsunami affecting the eastern coast of New Zealand, it is still important to develop an assessment of the worst scenarios of earthquake generated tsunamis from this source. In particular, the Sumatra 2004 and Tohuku 2011 tsunami events have suggested that a magnitude Mw 9 to 9.5 subduction megathrust earthquake is a plausible scenario.
Merian’s formula was used to obtain the natural resonant period of Mercury Bay and 17 scenarios of tsunamigenic earthquakes were simulated using the tsunami model COMCOT version 1.7. Those scenarios included the recent various combination of the Kermadec earthquake, and hypothetical earthquakes that rupture the northern, middle, southern parts of Kermadec Trench. The results demonstrate that most of the initial tsunami waves generated by Kermadec Trench earthquakes are negative waves that arrive in the Bay within 56 to 158 minutes of the earthquake. This may explain the observed historical pattern of enhanced amplification of the troughs. However, significant amplification of the crests, producing waves that would threaten Whitianga Township, are generated by Kermadec earthquakes with magnitudes greater than Mw 8.5.
From the spectral analysis of each tsunami model, Mercury Bay showed a consistent response of about 52 minutes dominant period. This period is also shown as the period of the Mercury Bay when tsunami is absent. In response to distant tsunamis, it seems that the geometry of the Mercury Bay control their periods as they enter the bay. Both the 2011 Tohoku and 2010 Chilean Events have the dominant periods close to the Mercury Bay period at 47 and 51 minutes respectively.

year: 2012

title: The pedagogical architecture of modern learning environments in four New Zealand secondary schools

authors: Hest, Julie Badeena

subjects: Learning environments

abstract: The New Zealand Ministry of Education has committed significant resources to develop state-owned school buildings that are purposefully built with quality materials, embrace internet capable technology and contain large, flexible learning spaces. Schools and classrooms built in this manner have been referred to as modern learning environments (MLEs). The development of MLEs was to improve the quality of school property infrastructure and increase student achievement with learning environments that support 21ˢᵗ-century teaching and learning. Initially, there was quite specific guidance on building and design standards for MLEs, but there was limited guidance on how to change teaching and learning practices to match with the physical changes of learning environments.  
	This thesis reports on qualitative multi-site research that explored teaching and learning in four New Zealand secondary schools that followed the requirement to adopt MLEs. Data was collected at each school via document review, a semi-structured interview with the principal, semi-structured interviews with teachers who taught in the MLEs and a focus group discussion with students who were timetabled to the MLEs. Across data sources, the main foci were (1) to investigate how the concepts of learners, educators, content and resources were interpreted and organised in the MLEs and (2) to explore what those in MLEs considered 21ˢᵗ-century skills and competencies to be and how these were being developed in learners.
The employed methodology offered primacy to the participants' understandings and experiences to help make visible the operation of MLEs from the varying perspectives of those involved in daily teaching and learning in these environments. Viewing the MLES in the four schools this way identified an observable gap between the potential that literature presumes MLEs may contain to develop 21ˢᵗ-century skills and competencies in learners and the realities of the daily operations of these learning environments. This gap is visible when considering how underpinning concepts related to the operation of MLEs are employed and when exploring individual reflections on how aspects of the physical space of MLEs may enable or constrain teaching and learning practices. Viewing MLEs this way also demonstrated how influential participants' individual perspectives were when limited guidance on how to change teaching and learning practices was offered, and therefore how essential purposeful time to reflect with colleagues is when collaboration is a valued or required aspect of a learning environment. Additionally, viewing MLEs this way suggests teaching and learning in an MLE deprivatises both teacher and student practice by making teacher and student actions visible to colleagues and peers in a way they were not visible in pre-MLE learning environments. 
The approach taken in this thesis to explore the phenomena of MLEs in the New Zealand secondary school context contributes to the emerging discourse around the development and understanding of MLEs from the perspectives of those involved in the reality of teaching and learning in such spaces. By making visible the reality of the use of MLEs, this research can be used to develop support for those who carry out teaching and learning in these environments.

text: The pedagogical architecture of modern learning environments in four New Zealand secondary schools The New Zealand Ministry of Education has committed significant resources to develop state-owned school buildings that are purposefully built with quality materials, embrace internet capable technology and contain large, flexible learning spaces. Schools and classrooms built in this manner have been referred to as modern learning environments (MLEs). The development of MLEs was to improve the quality of school property infrastructure and increase student achievement with learning environments that support 21ˢᵗ-century teaching and learning. Initially, there was quite specific guidance on building and design standards for MLEs, but there was limited guidance on how to change teaching and learning practices to match with the physical changes of learning environments.  
	This thesis reports on qualitative multi-site research that explored teaching and learning in four New Zealand secondary schools that followed the requirement to adopt MLEs. Data was collected at each school via document review, a semi-structured interview with the principal, semi-structured interviews with teachers who taught in the MLEs and a focus group discussion with students who were timetabled to the MLEs. Across data sources, the main foci were (1) to investigate how the concepts of learners, educators, content and resources were interpreted and organised in the MLEs and (2) to explore what those in MLEs considered 21ˢᵗ-century skills and competencies to be and how these were being developed in learners.
The employed methodology offered primacy to the participants' understandings and experiences to help make visible the operation of MLEs from the varying perspectives of those involved in daily teaching and learning in these environments. Viewing the MLES in the four schools this way identified an observable gap between the potential that literature presumes MLEs may contain to develop 21ˢᵗ-century skills and competencies in learners and the realities of the daily operations of these learning environments. This gap is visible when considering how underpinning concepts related to the operation of MLEs are employed and when exploring individual reflections on how aspects of the physical space of MLEs may enable or constrain teaching and learning practices. Viewing MLEs this way also demonstrated how influential participants' individual perspectives were when limited guidance on how to change teaching and learning practices was offered, and therefore how essential purposeful time to reflect with colleagues is when collaboration is a valued or required aspect of a learning environment. Additionally, viewing MLEs this way suggests teaching and learning in an MLE deprivatises both teacher and student practice by making teacher and student actions visible to colleagues and peers in a way they were not visible in pre-MLE learning environments. 
The approach taken in this thesis to explore the phenomena of MLEs in the New Zealand secondary school context contributes to the emerging discourse around the development and understanding of MLEs from the perspectives of those involved in the reality of teaching and learning in such spaces. By making visible the reality of the use of MLEs, this research can be used to develop support for those who carry out teaching and learning in these environments.

year: 2022

title: Lake Rotokakahi water quality update 1990-2011

authors: Butterworth, Joseph

subjects: Lake Rotokakahi

abstract: Lake Rotokakahi is an Iwi-owned lake administered by the Lake Rotokakahi Board of Control on Behalf of lake owners who are descendants from the Ngāti Tumatawera and Tūhourangi hapū of Te Arawa. It is mesotrophic (moderate water quality) lake with an area of 4.4 km² comprised of exotic forestry (57.1%), pasture (26.3%) and regenerating indigenous forest/scrub (16.6%).

text: Lake Rotokakahi water quality update 1990-2011 Lake Rotokakahi is an Iwi-owned lake administered by the Lake Rotokakahi Board of Control on Behalf of lake owners who are descendants from the Ngāti Tumatawera and Tūhourangi hapū of Te Arawa. It is mesotrophic (moderate water quality) lake with an area of 4.4 km² comprised of exotic forestry (57.1%), pasture (26.3%) and regenerating indigenous forest/scrub (16.6%).

year: 2012