title: Radial evolution of cross helicity in high-latitude solar wind

authors: Breech, Ben

subjects: solar wind

abstract: We employ a turbulence transport theory to explain the high-latitude radial evolution of cross helicity, or Alfvénicity, observed by the Ulysses spacecraft. Evolution is slower than at low latitudes due to weakened shear driving.

text: Radial evolution of cross helicity in high-latitude solar wind We employ a turbulence transport theory to explain the high-latitude radial evolution of cross helicity, or Alfvénicity, observed by the Ulysses spacecraft. Evolution is slower than at low latitudes due to weakened shear driving.

year: 2005

title: Testing for bubbles in time series data using long historical series

authors: Hu, Yang

subjects: thesis with publication

abstract: The concept of asset price bubble has drawn a large amount of academic attention. A bubble is commonly defined as where the asset price is not justified by expectations of the fundamentals. The empirical characteristics of a bubble are widely regarded as a dramatic rise in asset prices in the early periods along with a sudden collapse, which have been observed in a wide range of financial markets including commodity, real estate and stock.
This thesis attempts to examine several well-noticed bubble episodes in history, for example, the Mississippi Bubble in 1719, the South Sea Bubble in 1719-20, Japan’s asset price bubble during the 1980s and the more recent US real estate bubble in the early 2000s. One of the greatest contribution of this thesis is that it has provided econometric-based evidence to support the existence of these famous episodes for the first time using recently developed econometric tests. The origination and collapse dates for these identified episodes are coincided with the traditional view of famous bubbles.
This thesis not only tests for the existence of bubbles but also seeks to provide some empirical evidence to support the existence of bubble spillovers/contagion using the most-documented bubble episodes. The first example considered in this thesis is whether financial bubbles/crises spill-over to housing markets in Amsterdam, Norway and France. The second example is considered for a number of British financial organisations during the South Sea episode in 1719-20 (e.g., the South Sea Company, the Bank of England, East India Company, London Assurance, Million Bank, the Royal African Company and the Royal Exchange Assurance). The South Sea Bubble seems to migrate to other organisations as the British share market was speculative for that period. The timings of some identified episodes can be viewed as possible evidence of spillovers or contagion for this important period in England. The third example looks at the Japan’s real estate and stock markets during the 1980-90s. Based on econometric tools, the findings indicate signs of bubble migration from Japan’s stock market to its real estate market for the first time. Even if this phenomenon has been observed in the literature, none of existing studies provide any solid evidences to support this claim.
This thesis investigates the long-run equilibrium relationship between house prices and economic fundamentals in the US based on quantile cointegration approaches for the first time. The presence of cointegration between house prices and fundamentals would imply convergence to a stable equilibrium relationship, suggesting a temporary run-up or drop in house prices would eventually come back to the equilibrium. By making use of quantile autoregressive distributed lag model (QARDL), this research explores the cointegration relationship across the whole
conditional distribution.

text: Testing for bubbles in time series data using long historical series The concept of asset price bubble has drawn a large amount of academic attention. A bubble is commonly defined as where the asset price is not justified by expectations of the fundamentals. The empirical characteristics of a bubble are widely regarded as a dramatic rise in asset prices in the early periods along with a sudden collapse, which have been observed in a wide range of financial markets including commodity, real estate and stock.
This thesis attempts to examine several well-noticed bubble episodes in history, for example, the Mississippi Bubble in 1719, the South Sea Bubble in 1719-20, Japan’s asset price bubble during the 1980s and the more recent US real estate bubble in the early 2000s. One of the greatest contribution of this thesis is that it has provided econometric-based evidence to support the existence of these famous episodes for the first time using recently developed econometric tests. The origination and collapse dates for these identified episodes are coincided with the traditional view of famous bubbles.
This thesis not only tests for the existence of bubbles but also seeks to provide some empirical evidence to support the existence of bubble spillovers/contagion using the most-documented bubble episodes. The first example considered in this thesis is whether financial bubbles/crises spill-over to housing markets in Amsterdam, Norway and France. The second example is considered for a number of British financial organisations during the South Sea episode in 1719-20 (e.g., the South Sea Company, the Bank of England, East India Company, London Assurance, Million Bank, the Royal African Company and the Royal Exchange Assurance). The South Sea Bubble seems to migrate to other organisations as the British share market was speculative for that period. The timings of some identified episodes can be viewed as possible evidence of spillovers or contagion for this important period in England. The third example looks at the Japan’s real estate and stock markets during the 1980-90s. Based on econometric tools, the findings indicate signs of bubble migration from Japan’s stock market to its real estate market for the first time. Even if this phenomenon has been observed in the literature, none of existing studies provide any solid evidences to support this claim.
This thesis investigates the long-run equilibrium relationship between house prices and economic fundamentals in the US based on quantile cointegration approaches for the first time. The presence of cointegration between house prices and fundamentals would imply convergence to a stable equilibrium relationship, suggesting a temporary run-up or drop in house prices would eventually come back to the equilibrium. By making use of quantile autoregressive distributed lag model (QARDL), this research explores the cointegration relationship across the whole
conditional distribution.

year: 2019

title: Evaluation of land in Wairoa District for potential horticultural development

authors: Rau, Johnathon Taukiri

subjects: land suitability

abstract: The Wairoa District, on the East Coast of the North Island of New Zealand has less horticultural development than areas to the north and south. The objective of this study was to provide information to help inform landowners who may wish to invest in horticulture which could improve the economic situation of the district.
Field work involving local scale climate mapping and soil characterisation of areas with potential for horticulture in Wairoa District was completed in 2017. Constructed climate and topographical maps with existing soil maps were evaluated against known crop growth requirements to produce crop potential maps identifying areas with potential for crop production. Horticultural crops included in this study include kiwifruit, apples, cherries. Alternative crops include hemp and poppies.
Between mid-April – 31 October 2017, 45 portable iButton temperature loggers were deployed throughout Land Use Capability classes 1-3 in the Wairoa District and were set to record hourly temperature. When regressed against nearby climate stations, long term (18 -26 years) temperature datasets were derived from the short term iButton datasets. MODIS satellite images were also analysed to help identify areas prone to frost. From the long-term datasets local scale chill hour, growing degree days and October frost risk maps were constructed for the Wairoa District. For the central area from Wairoa to Frasertown, chill hours were estimated to range between 600 – 900, growing degree days 1300 – 1400 and October frost risk less than 25%.
From four representative soil types, horizon samples were taken to determine the soils physical properties including each horizons Total Available Water Holding Capacity (TAWHC). Horizon TAWHC for each soil type were summed to give TAWHC to 1 meter which along with 21 years of estimated daily rainfall and potential evapotranspiration were used in a soil water balance model to estimate seasonal crop irrigation requirements. Irrigation estimates for kiwifruit compared well against published values ranging between mean 204 – 247 mm.
The crop potential maps with seasonal crop irrigation estimates can enhance a land owner’s ability to make informed decisions resulting in economic benefit to whanau, community and the Wairoa District.

text: Evaluation of land in Wairoa District for potential horticultural development The Wairoa District, on the East Coast of the North Island of New Zealand has less horticultural development than areas to the north and south. The objective of this study was to provide information to help inform landowners who may wish to invest in horticulture which could improve the economic situation of the district.
Field work involving local scale climate mapping and soil characterisation of areas with potential for horticulture in Wairoa District was completed in 2017. Constructed climate and topographical maps with existing soil maps were evaluated against known crop growth requirements to produce crop potential maps identifying areas with potential for crop production. Horticultural crops included in this study include kiwifruit, apples, cherries. Alternative crops include hemp and poppies.
Between mid-April – 31 October 2017, 45 portable iButton temperature loggers were deployed throughout Land Use Capability classes 1-3 in the Wairoa District and were set to record hourly temperature. When regressed against nearby climate stations, long term (18 -26 years) temperature datasets were derived from the short term iButton datasets. MODIS satellite images were also analysed to help identify areas prone to frost. From the long-term datasets local scale chill hour, growing degree days and October frost risk maps were constructed for the Wairoa District. For the central area from Wairoa to Frasertown, chill hours were estimated to range between 600 – 900, growing degree days 1300 – 1400 and October frost risk less than 25%.
From four representative soil types, horizon samples were taken to determine the soils physical properties including each horizons Total Available Water Holding Capacity (TAWHC). Horizon TAWHC for each soil type were summed to give TAWHC to 1 meter which along with 21 years of estimated daily rainfall and potential evapotranspiration were used in a soil water balance model to estimate seasonal crop irrigation requirements. Irrigation estimates for kiwifruit compared well against published values ranging between mean 204 – 247 mm.
The crop potential maps with seasonal crop irrigation estimates can enhance a land owner’s ability to make informed decisions resulting in economic benefit to whanau, community and the Wairoa District.

year: 2018