Paul Whitfield - Academia.edu (original) (raw)

Papers by Paul Whitfield

2011 GEOSS Workshop XLI, 2011

ABSTRACT Presents a collection of slides covering the following topics: water quality monitoring ... more ABSTRACT Presents a collection of slides covering the following topics: water quality monitoring strategy; contaminants; data collection and analysis.

Estuarine and Coastal Marine Science, 1976

Http Dx Doi Org 10 4296 Cwrj3202161, Jan 23, 2013

Pure and Applied Geophysics, 2014

Limnology and Oceanography, 1981

... As not-ed by Hem (1970) few, if any, streams fit such conditions, and many models have been p... more ... As not-ed by Hem (1970) few, if any, streams fit such conditions, and many models have been proposed to account for discrepan-cies in the overall relationship (eg Kelso and Maccrimmon 1969; Sanders and Ad-rian 1978; Johnson 1979). ...

Http Dx Doi Org 10 4296 Cwrj3404467, Jan 23, 2013

ABSTRACT

Paul H. Whitlield, Normand Rousseau'. and Eric Michnowskyz nland Waters. ... Nle... more Paul H. Whitlield, Normand Rousseau'. and Eric Michnowskyz nland Waters. ... Nleasurements of stleam pH and alkalinitv. and lain pH ancl acidit,v nere madc on site t'ithin 30 minutes of collection usin€i standard analvtical and QA/QC mcthods (Enrironment Canada 1979). ...

Agu Spring Meeting Abstracts, May 1, 2004

A case study of an unconfined aquifer in the Grand Forks valley in south-central BC was used to d... more A case study of an unconfined aquifer in the Grand Forks valley in south-central BC was used to develop methodology for linking climate models, hydrologic models, and groundwater models to investigate future impacts of climate change on groundwater resources. A three dimensional groundwater flow model of variable spatial resolution (constrained by borehole spacing) was implemented in MODFLOW, and calibrated to observation well data. Multiple scenarios of the hydraulic conductivity fields were used in a sensitivity analysis. A new methodology was developed for generating spatially-distributed and temporally-varying recharge zonation for the surficial aquifer, using GIS linked to the one-dimensional HELP (USEPA) hydrologic model that estimates aquifer recharge. The recharge model accounts for soil distribution, vadose zone depth and hydraulic conductivity, extent of impermeable areas, surficial geology, and vadose zone thickness. Production well pumping and irrigation return flow during the summer season were included in recharge computations. Although recharge was computed as monthly averages per climate scenario, it is driven by physically-based daily weather inputs generated by a stochastic weather generator and calibrated to local observed climate. Four year long climate scenarios were run, each representing one typical year in the present and future (2020s, 2050s, and 2080s), by perturbing the historical weather according to the downscaled CGCM1 general circulation model results (Environment Canada). CGCM1 model outputs were calibrated for local conditions during the downscaling procedure. These include absolute and relative changes in precipitation; including indirect measures of precipitation intensity, dry and wet spell lengths, temperature, and solar radiation for the evapotranspiration model. CGCM1 downscaling was also used to predict basin-scale runoff for the Kettle River upstream of Grand Forks. This river exerts strong control on the groundwater levels in the aquifer and physically-based discharge predictions were used in the transient groundwater flow model. Modeled discharge hydrographs were converted to river stage hydrographs at each of 123 river segments, and interpolated between known river channel cross-sections. Stage-discharge curves were estimated using the BRANCH model and calibrated to observed historical data. River channels were represented in three-dimensions using a high grid density (14 to 25 m) in MODFLOW, which were mapped onto river segments. River stage schedules along the 26 km long meandering channel were imported at varying, but high, temporal resolution (1 to 5 days) for every cell location independently. Head differences were computed at each time step for historical and future, mapped in GIS and linked to the MODFLOW model. Temporal changes in mass balance components show relations between pumping, storage, recharge, and flow. Within an annual cycle and between climate scenarios the results show different spatial and temporal distributions in groundwater conditions. Groundwater levels near the river floodplain are predicted to be lower earlier in the year under future climate scenarios, but away from rivers, groundwater levels increase slightly due to the predicted increase in recharge.

Http Dx Doi Org 10 4296 Cwrj3404303, Jan 23, 2013

... 2007. Comparative study of suspended sediment concentrations downstream of harvested peat bog... more ... 2007. Comparative study of suspended sediment concentrations downstream of harvested peat bogs. Environmental Monitoring and Assessment 135: 369-382. Quinton, WL, M. Hayashi, and LE Chasmer. 2009. ... Smit, R., OM Bragg, and HAP . Ingram. 1999. ...

Hydrology Research, 2013

The quality (i.e. the degree of uncertainty that results from the interpretation and analysis) of... more The quality (i.e. the degree of uncertainty that results from the interpretation and analysis) of information dictates its value for decision making. There has been much progress towards improving information on the water budgets of ungauged basins by improving knowledge, tools and techniques during the Prediction in Ungauged Basins (PUB) initiative. These improvements, at least in Canada, have come through efforts in both hydrological process and statistical hydrology research. This paper is a review of some recent Canadian PUB efforts to use data to generate information and reduce uncertainty about the hydrological regimes of ungauged basins. The focus is on the Canadian context and the problems it presents, but the lessons learned are applicable to other countries with similar challenges. With a large land mass that is relatively poorly gauged, novel approaches have had to be developed to extract the most information from the available data. It can be difficult in Canada to find gauged or research basins sufficiently similar to ungauged sites of interest that contain the data required to force either statistical or deterministic models. Many statistical studies have improved information or at least an understanding of the quality of that information, of ungauged basin streamflow regimes using innovative regression-based approaches and pooled frequency analysis. Hydrological process research has reduced knowledge uncertainty, particularly in regard to cold regions processes, and this situation has led to the development of new algorithms that are reducing predictive uncertainty. There remains much to do. Current progress has created an opportunity to better integrate statistical and deterministic models via data assimilation of regionalization model estimates and those from coupled atmospheric-hydrological models. Aspects of such a modelling system could also provide more robust uncertainty analyses than traditional approaches.

Http Dx Doi Org 10 1175 Jhm D 13 0140 1, Sep 25, 2014

ABSTRACT This paper presents a review and assessment of four nontraditional similarity metrics th... more ABSTRACT This paper presents a review and assessment of four nontraditional similarity metrics that can be applied to hydrological and meteorological data. These metrics are 1) the uncentered correlation coefficient, 2) the Hodgkin–Richards index, 3) the Petke index, and 4) the Wang–Bovik index. The first metric has been widely used in hydrometeorology, and the other three have been proposed in other disciplines for similarity analysis. It is demonstrated that these similarity metrics, in their original formulations, either do not actually have the purported advantage over the traditional Pearson correlation coefficient or are not suitable for some hydrometeorological applications. They are reformulated in this study to address these deficiencies. The resulting modified metrics are unitless, bounded, and proportional to the Pearson correlation coefficient, and three of them have the confirmed advantage of explicitly penalizing for differences in the mean and/or in the variance. Two application examples are used to demonstrate the applicability of these similarity metrics in hydrometeorology. A metavalidation model and a graphical tool (Taylor diagram) are used to evaluate the performances of these similarity metrics. In a case study of analog analysis, the Wang–Bovik index stands out as the best metric for simulation of the human perception of similarity between two-dimensional patterns, whereas the modified Petke index and the traditional root-mean-square distance may perform slightly better than the others in the regions with a very large difference between the variances.

Http Dx Doi Org 10 4296 Cwrj2011 905, Jan 23, 2013

... Wade and Whitfield [22] describe variations in the impacts of rainfall events, and the impact... more ... Wade and Whitfield [22] describe variations in the impacts of rainfall events, and the impact of a sewage spill. ... 2. This example was observed, using the methods described by Whitfield andWade, where pH and water temperature were observed at one-minute intervals [16, 24]. ...

Environment International a Journal of Environmental Science Risk and Health, 1995

Natural cycles, particularly diurnal and seasonal cycles, dominate most environmental processes. ... more Natural cycles, particularly diurnal and seasonal cycles, dominate most environmental processes. Transients events are significant deviations from these usual variations. Transient events may have a duration from seconds to days and may occur naturally or as a result of man's activity. Events, which occur on occasion, could be considered on the basis of frequency of occurrence, and of duration of occurrence. In general, these events are rare relative to the density of data which are collected. Many data collection programs fail to identify transient events because of insufficient sampling. High-frequency electronic monitoring of water quality produces a record which contains seasonal, diurnal, transient events, and noise. A method of processing large volumes of data using spectral analysis techniques is described. The methodology is based on the separation of frequency components. This allows the examination of natural cycles, noise, and transient events. This technique allows screening of individual and multiple signals to allow confirmation and classification of transient events.

The purpose of Ntttts" is to periotliL'ully publish short pt4tet\ (t\pi(oLl\ L?s.t thanJi|e poges... more The purpose of Ntttts" is to periotliL'ully publish short pt4tet\ (t\pi(oLl\ L?s.t thanJi|e poges in [engtlt). There is no \ pe(ili( .fonnLtt or .otient requiretlJor ttnitle.s pultlished here, hut tll papers will be peer-revieted ont] tnust l)e stientilicalb cratlible. Authors DtLt\'(.onto(J the Editor ttltout tha suitohilin ol ntcutust'tipts litr tli.; section.

Canadian Water Resources Journal, 2009

Natural bogs are generally surrounded by a zone of hydrologic, hydrochemical, and ecological grad... more Natural bogs are generally surrounded by a zone of hydrologic, hydrochemical, and ecological gradients called a lagg. In laggs, large changes over short lateral distances result in distinctive ecological gradients and vegetation patterns. Part of the restoration planning challenge for Burns Bog involves recreating such water and chemistry gradients to establish and maintain conditions for appropriate plant and animal communities that reflect natural transitions from nutrient-poor bog to adjacent mineral-soil-influenced wetlands. We present a conceptual model inferred from historic air photos and vegetation maps from the margins of Burns Bog and theorize how particular vegetation represents the hydrological and hydrochemical gradients of the past that existed in transition to surrounding landscapes. Understanding lagg ecosystems and how they function is important not only to restoring the ecological integrity of Burns Bog, but also to developing a conceptual model useful for predicting and interpreting these gradients in other peatlands.

2011 GEOSS Workshop XLI, 2011

ABSTRACT Presents a collection of slides covering the following topics: water quality monitoring ... more ABSTRACT Presents a collection of slides covering the following topics: water quality monitoring strategy; contaminants; data collection and analysis.

Estuarine and Coastal Marine Science, 1976

Http Dx Doi Org 10 4296 Cwrj3202161, Jan 23, 2013

Pure and Applied Geophysics, 2014

Limnology and Oceanography, 1981

... As not-ed by Hem (1970) few, if any, streams fit such conditions, and many models have been p... more ... As not-ed by Hem (1970) few, if any, streams fit such conditions, and many models have been proposed to account for discrepan-cies in the overall relationship (eg Kelso and Maccrimmon 1969; Sanders and Ad-rian 1978; Johnson 1979). ...

Http Dx Doi Org 10 4296 Cwrj3404467, Jan 23, 2013

ABSTRACT

Paul H. Whitlield, Normand Rousseau'. and Eric Michnowskyz nland Waters. ... Nle... more Paul H. Whitlield, Normand Rousseau'. and Eric Michnowskyz nland Waters. ... Nleasurements of stleam pH and alkalinitv. and lain pH ancl acidit,v nere madc on site t'ithin 30 minutes of collection usin€i standard analvtical and QA/QC mcthods (Enrironment Canada 1979). ...

Agu Spring Meeting Abstracts, May 1, 2004

A case study of an unconfined aquifer in the Grand Forks valley in south-central BC was used to d... more A case study of an unconfined aquifer in the Grand Forks valley in south-central BC was used to develop methodology for linking climate models, hydrologic models, and groundwater models to investigate future impacts of climate change on groundwater resources. A three dimensional groundwater flow model of variable spatial resolution (constrained by borehole spacing) was implemented in MODFLOW, and calibrated to observation well data. Multiple scenarios of the hydraulic conductivity fields were used in a sensitivity analysis. A new methodology was developed for generating spatially-distributed and temporally-varying recharge zonation for the surficial aquifer, using GIS linked to the one-dimensional HELP (USEPA) hydrologic model that estimates aquifer recharge. The recharge model accounts for soil distribution, vadose zone depth and hydraulic conductivity, extent of impermeable areas, surficial geology, and vadose zone thickness. Production well pumping and irrigation return flow during the summer season were included in recharge computations. Although recharge was computed as monthly averages per climate scenario, it is driven by physically-based daily weather inputs generated by a stochastic weather generator and calibrated to local observed climate. Four year long climate scenarios were run, each representing one typical year in the present and future (2020s, 2050s, and 2080s), by perturbing the historical weather according to the downscaled CGCM1 general circulation model results (Environment Canada). CGCM1 model outputs were calibrated for local conditions during the downscaling procedure. These include absolute and relative changes in precipitation; including indirect measures of precipitation intensity, dry and wet spell lengths, temperature, and solar radiation for the evapotranspiration model. CGCM1 downscaling was also used to predict basin-scale runoff for the Kettle River upstream of Grand Forks. This river exerts strong control on the groundwater levels in the aquifer and physically-based discharge predictions were used in the transient groundwater flow model. Modeled discharge hydrographs were converted to river stage hydrographs at each of 123 river segments, and interpolated between known river channel cross-sections. Stage-discharge curves were estimated using the BRANCH model and calibrated to observed historical data. River channels were represented in three-dimensions using a high grid density (14 to 25 m) in MODFLOW, which were mapped onto river segments. River stage schedules along the 26 km long meandering channel were imported at varying, but high, temporal resolution (1 to 5 days) for every cell location independently. Head differences were computed at each time step for historical and future, mapped in GIS and linked to the MODFLOW model. Temporal changes in mass balance components show relations between pumping, storage, recharge, and flow. Within an annual cycle and between climate scenarios the results show different spatial and temporal distributions in groundwater conditions. Groundwater levels near the river floodplain are predicted to be lower earlier in the year under future climate scenarios, but away from rivers, groundwater levels increase slightly due to the predicted increase in recharge.

Http Dx Doi Org 10 4296 Cwrj3404303, Jan 23, 2013

... 2007. Comparative study of suspended sediment concentrations downstream of harvested peat bog... more ... 2007. Comparative study of suspended sediment concentrations downstream of harvested peat bogs. Environmental Monitoring and Assessment 135: 369-382. Quinton, WL, M. Hayashi, and LE Chasmer. 2009. ... Smit, R., OM Bragg, and HAP . Ingram. 1999. ...

Hydrology Research, 2013

The quality (i.e. the degree of uncertainty that results from the interpretation and analysis) of... more The quality (i.e. the degree of uncertainty that results from the interpretation and analysis) of information dictates its value for decision making. There has been much progress towards improving information on the water budgets of ungauged basins by improving knowledge, tools and techniques during the Prediction in Ungauged Basins (PUB) initiative. These improvements, at least in Canada, have come through efforts in both hydrological process and statistical hydrology research. This paper is a review of some recent Canadian PUB efforts to use data to generate information and reduce uncertainty about the hydrological regimes of ungauged basins. The focus is on the Canadian context and the problems it presents, but the lessons learned are applicable to other countries with similar challenges. With a large land mass that is relatively poorly gauged, novel approaches have had to be developed to extract the most information from the available data. It can be difficult in Canada to find gauged or research basins sufficiently similar to ungauged sites of interest that contain the data required to force either statistical or deterministic models. Many statistical studies have improved information or at least an understanding of the quality of that information, of ungauged basin streamflow regimes using innovative regression-based approaches and pooled frequency analysis. Hydrological process research has reduced knowledge uncertainty, particularly in regard to cold regions processes, and this situation has led to the development of new algorithms that are reducing predictive uncertainty. There remains much to do. Current progress has created an opportunity to better integrate statistical and deterministic models via data assimilation of regionalization model estimates and those from coupled atmospheric-hydrological models. Aspects of such a modelling system could also provide more robust uncertainty analyses than traditional approaches.

Http Dx Doi Org 10 1175 Jhm D 13 0140 1, Sep 25, 2014

ABSTRACT This paper presents a review and assessment of four nontraditional similarity metrics th... more ABSTRACT This paper presents a review and assessment of four nontraditional similarity metrics that can be applied to hydrological and meteorological data. These metrics are 1) the uncentered correlation coefficient, 2) the Hodgkin–Richards index, 3) the Petke index, and 4) the Wang–Bovik index. The first metric has been widely used in hydrometeorology, and the other three have been proposed in other disciplines for similarity analysis. It is demonstrated that these similarity metrics, in their original formulations, either do not actually have the purported advantage over the traditional Pearson correlation coefficient or are not suitable for some hydrometeorological applications. They are reformulated in this study to address these deficiencies. The resulting modified metrics are unitless, bounded, and proportional to the Pearson correlation coefficient, and three of them have the confirmed advantage of explicitly penalizing for differences in the mean and/or in the variance. Two application examples are used to demonstrate the applicability of these similarity metrics in hydrometeorology. A metavalidation model and a graphical tool (Taylor diagram) are used to evaluate the performances of these similarity metrics. In a case study of analog analysis, the Wang–Bovik index stands out as the best metric for simulation of the human perception of similarity between two-dimensional patterns, whereas the modified Petke index and the traditional root-mean-square distance may perform slightly better than the others in the regions with a very large difference between the variances.

Http Dx Doi Org 10 4296 Cwrj2011 905, Jan 23, 2013

... Wade and Whitfield [22] describe variations in the impacts of rainfall events, and the impact... more ... Wade and Whitfield [22] describe variations in the impacts of rainfall events, and the impact of a sewage spill. ... 2. This example was observed, using the methods described by Whitfield andWade, where pH and water temperature were observed at one-minute intervals [16, 24]. ...

Environment International a Journal of Environmental Science Risk and Health, 1995

Natural cycles, particularly diurnal and seasonal cycles, dominate most environmental processes. ... more Natural cycles, particularly diurnal and seasonal cycles, dominate most environmental processes. Transients events are significant deviations from these usual variations. Transient events may have a duration from seconds to days and may occur naturally or as a result of man's activity. Events, which occur on occasion, could be considered on the basis of frequency of occurrence, and of duration of occurrence. In general, these events are rare relative to the density of data which are collected. Many data collection programs fail to identify transient events because of insufficient sampling. High-frequency electronic monitoring of water quality produces a record which contains seasonal, diurnal, transient events, and noise. A method of processing large volumes of data using spectral analysis techniques is described. The methodology is based on the separation of frequency components. This allows the examination of natural cycles, noise, and transient events. This technique allows screening of individual and multiple signals to allow confirmation and classification of transient events.

The purpose of Ntttts" is to periotliL'ully publish short pt4tet\ (t\pi(oLl\ L?s.t thanJi|e poges... more The purpose of Ntttts" is to periotliL'ully publish short pt4tet\ (t\pi(oLl\ L?s.t thanJi|e poges in [engtlt). There is no \ pe(ili( .fonnLtt or .otient requiretlJor ttnitle.s pultlished here, hut tll papers will be peer-revieted ont] tnust l)e stientilicalb cratlible. Authors DtLt\'(.onto(J the Editor ttltout tha suitohilin ol ntcutust'tipts litr tli.; section.

Canadian Water Resources Journal, 2009

Natural bogs are generally surrounded by a zone of hydrologic, hydrochemical, and ecological grad... more Natural bogs are generally surrounded by a zone of hydrologic, hydrochemical, and ecological gradients called a lagg. In laggs, large changes over short lateral distances result in distinctive ecological gradients and vegetation patterns. Part of the restoration planning challenge for Burns Bog involves recreating such water and chemistry gradients to establish and maintain conditions for appropriate plant and animal communities that reflect natural transitions from nutrient-poor bog to adjacent mineral-soil-influenced wetlands. We present a conceptual model inferred from historic air photos and vegetation maps from the margins of Burns Bog and theorize how particular vegetation represents the hydrological and hydrochemical gradients of the past that existed in transition to surrounding landscapes. Understanding lagg ecosystems and how they function is important not only to restoring the ecological integrity of Burns Bog, but also to developing a conceptual model useful for predicting and interpreting these gradients in other peatlands.