title: Fluxes of Energy and Water Vapour from Grazed Pasture on a Mineral Soil in the Waikato

authors: Kuske, Tehani Janelle

subjects: eddy covariance

abstract: The eddy covariance (EC) technique was used to measure half hourly fluxes of energy and evaporation from 15 December 2007 to 30 November 2008 at the Scott Research Farm, located 7 km east of Hamilton. Many other supporting measurements of climate and soil variables were also made. The research addressed three objectives:
1. To examine the accuracy of the eddy covariance measurement technique.
2. Understand the surface partitioning of energy and water vapour on a diurnal to annual timescale.
3. Compare measurements of evaporation to methods of estimation.
Average energy balance closure at Scott Farm was deficient by 24%, comparable to published studies of up to 30%. Three lysimeter studies were carried out to help verify eddy covariance data. These resulted in the conclusions that; 1) lysimeter pots needed to be deeper to allow for vegetation rooting depths to be encompassed adequately; 2) forcing energy balance closure was not supported by two of the studies (summer and winter); 3) latent heat flux (λE) gap filling of night time EC data during winter over estimated values by about 10 W m-2; and 4) the spring lysimeter study verified eddy covariance measurements including the closure forcing method. Some uncertainty still exists as to the accuracy of both lysimeter and EC methods of evaporation measurement because both methods still have potential biases, however for the purpose of this study, it would appear data are sufficiently accurate to have confidence in results. Energy and water vapour fluxes varied on both a diurnal and seasonal timescale. Diurnally, fluxes were small or negative at night and were highest during the day, usually at solar noon. Seasonally, spring and summer had the highest energy and evaporation fluxes and winter rates were small but tended to exceed available energy supply. Evaporation was constrained by soil moisture availability during summer and by energy availability during winter. Estimated annual evaporation at Scott Farm was 755 mm, 72% of precipitation. Two evaporation models were compared to eddy covariance evaporation (EEC) measurements; the FAO56 Penman-Monteith model (Eo) and the Priestley-Taylor model (EPT). Both models over estimated evaporation during dry conditions and slightly under estimated during winter. The α coefficient that is applied to EPT was not constant and a seasonally adjusted value would be most appropriate. A crop coefficient of 1.13 is needed for Eo measurements during moist conditions. Eo began over estimating evaporation when soil moisture contents dropped below ~44%. A water stress adjustment was applied to both models which improved evaporation estimates, however early onset of drying was not able to be adjusted for. The adjusted Eo model is the most accurate overall, when compared to EEC.

text: Fluxes of Energy and Water Vapour from Grazed Pasture on a Mineral Soil in the Waikato The eddy covariance (EC) technique was used to measure half hourly fluxes of energy and evaporation from 15 December 2007 to 30 November 2008 at the Scott Research Farm, located 7 km east of Hamilton. Many other supporting measurements of climate and soil variables were also made. The research addressed three objectives:
1. To examine the accuracy of the eddy covariance measurement technique.
2. Understand the surface partitioning of energy and water vapour on a diurnal to annual timescale.
3. Compare measurements of evaporation to methods of estimation.
Average energy balance closure at Scott Farm was deficient by 24%, comparable to published studies of up to 30%. Three lysimeter studies were carried out to help verify eddy covariance data. These resulted in the conclusions that; 1) lysimeter pots needed to be deeper to allow for vegetation rooting depths to be encompassed adequately; 2) forcing energy balance closure was not supported by two of the studies (summer and winter); 3) latent heat flux (λE) gap filling of night time EC data during winter over estimated values by about 10 W m-2; and 4) the spring lysimeter study verified eddy covariance measurements including the closure forcing method. Some uncertainty still exists as to the accuracy of both lysimeter and EC methods of evaporation measurement because both methods still have potential biases, however for the purpose of this study, it would appear data are sufficiently accurate to have confidence in results. Energy and water vapour fluxes varied on both a diurnal and seasonal timescale. Diurnally, fluxes were small or negative at night and were highest during the day, usually at solar noon. Seasonally, spring and summer had the highest energy and evaporation fluxes and winter rates were small but tended to exceed available energy supply. Evaporation was constrained by soil moisture availability during summer and by energy availability during winter. Estimated annual evaporation at Scott Farm was 755 mm, 72% of precipitation. Two evaporation models were compared to eddy covariance evaporation (EEC) measurements; the FAO56 Penman-Monteith model (Eo) and the Priestley-Taylor model (EPT). Both models over estimated evaporation during dry conditions and slightly under estimated during winter. The α coefficient that is applied to EPT was not constant and a seasonally adjusted value would be most appropriate. A crop coefficient of 1.13 is needed for Eo measurements during moist conditions. Eo began over estimating evaporation when soil moisture contents dropped below ~44%. A water stress adjustment was applied to both models which improved evaporation estimates, however early onset of drying was not able to be adjusted for. The adjusted Eo model is the most accurate overall, when compared to EEC.

year: 2009

title: Proceedings of the Third Computing Women Congress (CWC 2008): Student papers

authors: Hinze, Annika

subjects: solar exposure

abstract: The Third Computing Women Congress was held at the University of Waikato, Hamilton, New Zealand from February 11th to 13th, 2008. The Computing Women Congress (CWC) is a Summer University for women in Computer Science. It is a meeting-place for female students, academics and professionals who study or work in Information Technology. CWC provides a forum to learn about and share the latest ideas of computing related topics in a supportive environment. CWC provides an open, explorative learning and teaching environment. Experimentation with new styles of learning is encouraged, with an emphasis on hands-on experience and engaging participatory techniques.

text: Proceedings of the Third Computing Women Congress (CWC 2008): Student papers The Third Computing Women Congress was held at the University of Waikato, Hamilton, New Zealand from February 11th to 13th, 2008. The Computing Women Congress (CWC) is a Summer University for women in Computer Science. It is a meeting-place for female students, academics and professionals who study or work in Information Technology. CWC provides a forum to learn about and share the latest ideas of computing related topics in a supportive environment. CWC provides an open, explorative learning and teaching environment. Experimentation with new styles of learning is encouraged, with an emphasis on hands-on experience and engaging participatory techniques.

year: 2008-02

title: “This is not a riot, it is a protest”: A discourse analysis of prison violence in New Zealand news media

authors: Membery, Liam

subjects: Prison Violence

abstract: This thesis examines the discourses of prison violence in the New Zealand news media. Prison violence is a pressing social issue that harms those involved and has permeating consequences for the institution. Prison riots, specifically, involve serious instances of disorder and violence that incur physical, psychological, social and economic harm. Despite prisons being private institutions, prison riots are public events that amass large social responses through news media coverage. The public often use news media to co-construct their perceptions of social phenomena, and policymakers use both public opinion and the news media to guide their decisions when shaping policy. Subsequently, the ways in which the news media discursively construct prison riots will have direct consequences for public attitudes and policy relating to prison violence, a phenomenon that exists outside of the public eye. However, there is currently no research that has examined discourses of prison violence and, further, what the consequences of these discourses may be. Therefore, using a Foucauldian approach to discourse analysis, this study examined the discourses in the news media representations of the large-scale prison violence at the Spring Hill Corrections Facility (2013) and Waikeria Prison (2020-2021). The results uncovered three discourses: the riot discourse, the gang discourse, and the protest discourse. The riot discourse was identified as dominant and constructed prison violence as an individualised issue perpetrated by inherently violent prisoners. The gang discourse worked in conjunction with the riot discourse, constructing prison violence as an individualised issue perpetrated by gang members. The protest discourse was identified as a counter-discourse and constructed the unrest at both facilities as protests against living conditions and inhumane treatment. Each discourse has consequences for public attitudes and in turn, penal policy and practice.

text: “This is not a riot, it is a protest”: A discourse analysis of prison violence in New Zealand news media This thesis examines the discourses of prison violence in the New Zealand news media. Prison violence is a pressing social issue that harms those involved and has permeating consequences for the institution. Prison riots, specifically, involve serious instances of disorder and violence that incur physical, psychological, social and economic harm. Despite prisons being private institutions, prison riots are public events that amass large social responses through news media coverage. The public often use news media to co-construct their perceptions of social phenomena, and policymakers use both public opinion and the news media to guide their decisions when shaping policy. Subsequently, the ways in which the news media discursively construct prison riots will have direct consequences for public attitudes and policy relating to prison violence, a phenomenon that exists outside of the public eye. However, there is currently no research that has examined discourses of prison violence and, further, what the consequences of these discourses may be. Therefore, using a Foucauldian approach to discourse analysis, this study examined the discourses in the news media representations of the large-scale prison violence at the Spring Hill Corrections Facility (2013) and Waikeria Prison (2020-2021). The results uncovered three discourses: the riot discourse, the gang discourse, and the protest discourse. The riot discourse was identified as dominant and constructed prison violence as an individualised issue perpetrated by inherently violent prisoners. The gang discourse worked in conjunction with the riot discourse, constructing prison violence as an individualised issue perpetrated by gang members. The protest discourse was identified as a counter-discourse and constructed the unrest at both facilities as protests against living conditions and inhumane treatment. Each discourse has consequences for public attitudes and in turn, penal policy and practice.

year: 2022