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Images, Alexander Turnbull Library

The cartoon is headed 'Whitebait - How to spot the difference.' Below are two frames; the one on the left shows a brown fish wearing goggles and breathing apparatus, it is from the East Coast and is described as 'drab brown' and 'tastes like dung'; the one on the right is pink and wears a sun hat and sunglasses, it is from the West Coast and is described as 'lightly tanned' and 'tastes like coconut'. Context: The whitebait from the east coast has been contaminated by the Canterbury earthquakes. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

A man representing the South Island stands under an umbrella representing 'hope' to shelter from a bucketload of water representing 'misfortune'. Context - in the last year apart from the usual droughts and floods the South Island has suffered the Pike River Mine disaster on 19 November 2010 in which 29 coal miners were killed, the 7.1 earthquake on 4 September 2010 in which there was a lot of damage but no deaths and now on 22 February 2011 a 6.3 magnitude earthquake which has probably killed more than 200 people (at this point the number is still not known) and caused more severe damage. The reason the apparently lesser magnitude quake caused more destruction is because it was very shallow, was in the middle of the day and struck very close to the centre of the city. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

The New Zealand public contemplate a dead drought stricken landscape. As well as lack of water, there is a lack of moderate pay scales for CEOs, satisfaction with EQC, quality TV, generous insurance companies, brilliant Solid Energy management, the integrity of John Banks (and by implication that of other MPs), quality education ministers, worthwhile overseas trips by the Prime Minister, 'clever' NZ First MPs and a boost for the West Coast among others. Considered from a Canterbury perspective, the drought of early 2013 becomes a symbol for many of the recent political and social ailments afflicting the land. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

The cartoon shows the hands of two people joined in mutual despair and kindness. One represents 'Christchurch' and the other the 'Pike River Mine'. Context - the 7.1 earthquake on 4 September 2010 in Christchurch in which there was a lot of damage but no deaths, the Pike River Mine disaster which occurred on the West Coast on 19 November 2010 and caused the deaths of 29 coal miners and now on 22 February 2011 a 6.3 magnitude earthquake in Christchurch which has probably killed more than 200 people (at this point the number is still not known) and caused much more severe damage. The reason the apparently lesser magnitude quake caused more destruction is because it was very shallow, was in the middle of the day and struck very close to the centre of the city. Colour and black and white versions of this cartoon are available Quantity: 2 digital cartoon(s).

Research Papers, Lincoln University

This report reviews the literature on regeneration requirements of main canopy tree species in Westland. Forests managed for production purposes have to be harvested in an ecologically sustainable way; to maintain their natural character, harvesting should facilitate regeneration of target species and ensure that their recruitment is in proportion to the extent of extraction. The reasons for species establishing at any point in time are unclear; however, they are probably related to the availability of suitable microsites for establishment, the size of the canopy openings formed by disturbance, and whether or not seeds are available at or around the time of the disturbance. Age structures from throughout Westland show that extensive, similar-aged, post-earthquake cohorts of trees are a feature of the region. This suggests that infrequent, massive earthquakes are the dominant coarse-scale disturbance agent, triggering episodes of major erosion and sedimentation and leaving a strong imprint in the forest structure. In other forests, flooding and catastrophic windthrow are major forms of disturbance. The findings suggest that, in general, large disturbances are required for conifer regeneration. This has implications for any sustained yield management of these forests if conifers are to remain an important component. Any harvesting should recognise the importance for tree establishment of: forest floor microsites, such as fallen logs and tree tip-up mounds; and the variable way in which canopy gaps are formed. Harvesting should maintain the 'patchy' nature of the natural forest—large patches of dense conifers interspersed with more heterogeneous patches of mixed species.This is a client report commissioned by West Coast Conservancy and funded from the Unprogrammed Science Advice fund.

Research papers, Victoria University of Wellington

<strong>Sea level rise is one consequence of Earth’s changing climate. Century-long tide gauge records show that global-mean sea-level rise reached 11-16 cm during the twentieth century at a mean rate of 1.2 mm/y. Today, the average rate of global-mean sea-level rise is higher at 3-4 mm/y and is expected to increase in the future. This represents a hazard to low elevation coastal zones worldwide. Yet, before global sea level projections can be used to characterise future coastal flood hazard at a local scale, the effects of tectonics (and other processes) that drive vertical land motion (VLM) must be considered. VLM is defined as the vertical velocity (uplift or subsidence) of the solid surface with respect to the centre of Earth. In this study, new VLM maps are generated over coastal strips in New Zealand, using Sentinel-1 InSAR and GNSS data.</strong>In New Zealand, measuring VLM using InSAR on naturally vegetated or agricultural land is difficult due to signal decorrelation. Along the rural Bay of Plenty coastal strip, I use a persistent-scatterer approach to generate a VLM map from both east-looking ascending and west-looking descending Sentinel-1 data between 2015-2021. Using time-series data over the same time period from a dense network of 20 GNSS sensors, I tie InSAR-derived line-of-sight velocity to the 2014 ITRF reference frame. I test two different methods for measuring VLM and compare the results against GNSS vertical velocity along the Bay of Plenty coast. Best results are achieved by first removing the interpolated horizontal GNSS velocity field from each of the InSAR datasets, before averaging the two VLM estimates. Measured VLM is between -3 and 3 mm/y, with negative values (subsidence) occurring within the low-lying Rangitāiki Plain and Ōpōtiki valley, and uplift across the elevated region west of Matatā.This thesis integrates geomorphological, geological, and historical levelling VLM records with modern satellite datasets to assess VLM across timescales ranging from 10 to 100,000 years at Matatā. Uplift rate has been variable through time, with average uplift over the last 300,000 years of 1 mm/y, 4.5 mm/y since 1720 years, 2 mm/y between 1950-1978, and 10 mm/y between 2004-2011. Previous modelling has shown that the best fit to the 2004-2011 rapid uplift rates is an inflating magmatic source at ~10 km depth beneath Matatā. To reconcile all data, I present a VLM model that consists of short-lived periods (7 years) of rapid uplift (10 mm/y), separated by longer periods (30 years) of lower background uplift (3 mm/y). The episodic nature of VLM at Matatā likely reflects short-lived periods of magmatic intrusion. Episodic VLM characterised by large rates of uplift (10 mm/y) has been seen at Taupō volcano, and other volcanic centers globally. It has been 12 years since the end of the last intrusion episode; this modelling suggest one may expect to observe increased uplift rates at Matatā in the coming decades. Densely populated urban coastal strips are most at risk from the effects of relative sea-level rise. At the same time, anthropogenic activities associated with urbanization, such as groundwater withdrawal, and land reclamation can lead to local land subsidence (LLS), further exacerbating the risk to urban infrastructure. LLS refers to subsidence relative to nearby land area assumed to be stable. In this thesis, I create the first high-resolution (10 m) maps of LLS at six urban coastal strips in New Zealand, with a combined length of 285 km, using Sentinel-1 InSAR data between 2018-2021. This analysis reveals 89% of urban coastal strips are subsiding at rates of -0.5 mm/y or greater, and 11% is subsiding at higher rates of -3.0 mm/y or greater. On average, subsidence is -0.6 to -2.9 mm/y higher at the coastal strip, compared to inland areas occupied by GNSS stations. This analysis also documents highly-localised hotspots of LLS, with subsidence rates of up to -15 mm/y. In Christchurch, rapid and localised subsidence (-8 mm/y) is observed within coastal suburbs New Brighton and Southshore. In most cities, the highest subsidence rates occur on land reclaimed in the early-late twentieth century, and in areas built on Holocene sediment. Time-series analysis of LLS at sites of reclaimed land shows both linear and non-linear rates of deformation over time periods of up to 6-8 years. This thesis highlights the variable exposure to relative sea-level rise of New Zealand coastal strips, and demonstrates that in many cases current rates of VLM should be expected to continue for the next few decades.