ASSESSMENT OF CHANGES IN PRECIPITATION INTENSITIES IN ONTARIO A Thesis Presented to The Faculty of Graduate Studies of The University of Guelph by BRANISLAVA VASIUEVIC In partial fulfilment of requirements for the degree of Master of Science December, 2007 © Branislava Vasiljevic, 2007 Library and Bibliotheque et 1*1 Archives Canada Archives Canada Published Heritage Direction du Branch Patrimoine de I'edition 395 Wellington Street 395, rue Wellington Ottawa ON K1A0N4 Ottawa ON K1A0N4 Canada Canada Your file Votre reference ISBN: 978-0-494-36577-9 Our file Notre reference ISBN: 978-0-494-36577-9 NOTICE: AVIS: The author has granted a non­ L'auteur a accorde une licence non exclusive exclusive license allowing Library permettant a la Bibliotheque et Archives and Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par telecommunication ou par Nnternet, preter, telecommunication or on the Internet, distribuer et vendre des theses partout dans loan, distribute and sell theses le monde, a des fins commerciales ou autres, worldwide, for commercial or non­ sur support microforme, papier, electronique commercial purposes, in microform, et/ou autres formats. paper, electronic and/or any other formats. The author retains copyright L'auteur conserve la propriete du droit d'auteur ownership and moral rights in et des droits moraux qui protege cette these. this thesis. Neither the thesis Ni la these ni des extraits substantiels de nor substantial extracts from it celle-ci ne doivent etre imprimes ou autrement may be printed or otherwise reproduits sans son autorisation. reproduced without the author's permission. In compliance with the Canadian Conformement a la loi canadienne Privacy Act some supporting sur la protection de la vie privee, forms may have been removed quelques formulaires secondaires from this thesis. ont ete enleves de cette these. While these forms may be included Bien que ces formulaires in the document page count, aient inclus dans la pagination, their removal does not represent il n'y aura aucun contenu manquant. any loss of content from the thesis. Canada ABSTRACT Branislava Vasiljevic Advisor: University of Guelph, 2007 Dr. Edward A. McBean The intensities of short-duration rainfalls are fundamental inputs to design of stormwater management infrastructure for urban areas. Such infrastructure, are designed, in part, to control urban flooding and require specification of storms for specific recurrence intervals. However, implicit in design tasks of stormwater infrastructure is the need for the infrastructure to function for many decades. Given that there is widespread evidence that climate change is likely occurring, there is extensive interest in whether the frequencies of urban storms are changing and hence, whether urban infrastructure designs need to be changed in response to the global climate change reality. To examine whether the recurrence intervals of severe storms are changing, historical records for thirteen locations distributed throughout Ontario are evaluated. The results of the analyses of the historical records for rainfall intensity/recurrence interval/duration are provided for each of these locations, and demonstrate there is evidence that rainfall intensities are, indeed, changing in Ontario. ACKNOWLEDGEMENTS I would like to acknowledge the many people who have supported me during my master's studies. I would first like to thank my Mentor, Dr Edward A. McBean, for his financial and moral support. While working with such an exceptional expert is one of the greatest honors I have had, it is his personal qualities that make me so proud to be his student. Many thanks for his brilliant ideas and extraordinary experience, which he shares so freely, his exceptional level of guidance throughout my research, and for two excellent courses. I would also like to express my gratitude to Professor McBean for the opportunity to be a part of a great multicultural community at the School of Engineering I would also like to acknowledge Dr Ramesh P. Rudra, for his participation on my advisory committee and financial support of this project I highly appreciate Dr Andrea Bradford, for an excellent course, and Professor Emeritus Dr Trevor Dickinson for useful advices. Special thanks to Goran Vrakela and Branko Jovanovic for their help and advice on software development; Laura Wagner and Brian Verspagen, from Conestoga-Rovers & Associates, for contributions regarding existing infrastructure analyses; and Joan Klaassen and Heather Auld, from Meteorological Service of Canada, for providing useful comments despite busy schedules. i I would like to thank my colleagues and dear friends at the School of Engineering: Ana, Cuit, Fernando Chantelle, Joel, Maryam, Mijin and Ash, for their great emotional support and empathy. Also, many thanks to my family and friends, for just being there. Last but not least, I would like to thank my husband for his encouragement, support, and patience during the past two years. Finally, this thesis is dedicated to my parents, Ljubinka and Blagoje Matic, for their tremendous and unconditional love and support during their lives. ii TABLE OF CONTENTS ACKNOWLEDGEMENTS i TABLE OF CONTENTS iii LIST OF TABLES v LIST OF FIGURES v CHAPTER 1 INTRODUCTION 1 1.1 RESEARCH MOTIVATION 1 1.2 OBJECTIVES 5 1.3. SCOPE OF THE THESIS 6 CHAPTER 2 LITERATURE REVIEW 8 2.1 METHODOLOGIES AND REVIEW OF CLIMATE CHANGE STUDIES 8 2.1.1 Methodologies Used in Previous Climate Change Studies 8 2.1.2 Preceding Climate Change Studies Review 11 2.2 LOCAL POINT RAINFALL DATA FREQUENCY ANALYSES 24 2.2.1 Probability Distributions 24 2.2.2 Recurrence Interval and Frequency Factor 27 2.2.3. IDF curves 29 2.3 TREND TEST 31 2.3.1 Linear regression 31 2.3.2 Mann- Kendall non - parametric test 32 CHAPTER 3 THEORETICAL BASE AND METHODOLOGY 33 3.1. DATA RANKING 33 3.1.1 The Annual Maxima 33 3.1.1 The Partial Duration Series 34 3.2 IDF CURVES 35 3.2.1 Extreme Value I distribution 36 3.2.2 Frequency Analyses 37 3.3 INTENSITY EQUATION COEFFICIENTS 38 3.3.1 The Log-Linear Regression 38 3.3.2 The Method of Least Squares 39 3.4 TREND DETECTION 40 iii 3.4.1 Linear Regression 40 3.4.2 Mann - Kendall Trend Test 40 3.5 CONFIDENCE INTERVAL AND FREQUENCY 42 CHAPTER 4 MODEL DEVELOPMENT AND RESULTS 45 4.1 INTRODUCTION 45 4.2 DATA AVAILABLE 46 4.3 LOCAL POINT IDF CURVES ANALYSES 49 4.3.1 Application of Model to IDF curves Temporal Change Analyses 53 4.3.2 Model Application to Seasonal Analyses in IDF curves 58 4.4 MODEL APPLICATION TO THE CASE STUDY AREA: WATERLOO STATION 66 4.4.1 IDF Curves Analyses ... 67 4.4.2 Intensity Equation Temporal Analyses 72 4.4.3 Evaluation of Existing Hydrological Model 75 4.5. RECURRENCE INTERVALS CONFIDENCE LIMITS 77 4.6 TREND ANALYSES FOR THE NUMBER OF DRY DAYS AND THE AMOUNT OF RAINFALL 85 CHAPTER 5 CONCLUSIONS AND RECOMMENDATIONS 88 5.1 CONCLUSIONS 88 5.2 RECOMMENDATIONS FOR FUTURE WORK 90 REFERENCES 92 APPENDIX A: Tables 98 APPENDIX B: Computer Programs 119 APPENDIX C: Confidence Intervals Calculations Example for 18 Samples at Waterloo Station 122 IV LIST OF TABLES Table 4.2 Annual missing data summary 48 Table 4.5 Trend Analyses Results for Seasonal Changes in IDF Curves for Twelve Stations Across Ontario 66 Table 4.6.1 IDF Curves Table 4.6.1 IDF Curves Evaluation for 2 Year Event Evaluation for 5 Year Event at Waterloo station at Waterloo station...68 Table 4.7 IDF Comparison between Different Periods of Observation for 2 and 5 Year Events at Waterloo Station 70 Table 4.8 IDF Curves Constants Comparison at Waterloo 73 Station for two Period of Observation with Existing IDF curves 73 Table 4.9 Stormwater Sewer Pipe Size Analyses Based on Various Scenarios in Terms of Heavy Rainfall Intensity for 5 Year Event at Waterloo/Kitchener location 76 Table 4.10 Summarized Results for Confidence Limits Calculations at Waterloo Station for Different Sample Size and Periods of Observation .83 Table4.11 Summarized Results for Mann-Kendall Trend Tests for 5% Level of Significance at 13 Locations in Ontario 86 Table 4.1 Meteorological stations used for analyses; Data are provided by Environment Canada; 98 Table 4.3.1 DELHI IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1962-1978 and 1979-1995 99 Table 4.3.2 PORT COLBORNE IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1962-1978 and 1979-1995 99 Table 4.3.3 PRESTON IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1970-1984 and 1985-1996.. 100 Table 4.3.4 SARNIA IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1970-1984 and 1985-2003 100 Table 4.3.5 WATERLOO IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1970-1984 and 1985-2003 101 Table 4.3.6 BOWMANVILLE IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1966 -1984 and 1985-2001 101 Table 4.3.7 BURKETON IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1969 -1984 and 1985-2001 102 Table 4.3.8 KINGSTON IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1960-1981 and 1982-2003 102 Table 4.3.9 ORILLIA IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1965-1978 and 1979-1992 103 v Table 4.3.10 OSHAWA IDF Curves Temporal Trend Analyses Changes in IDF Curves for Time Series: 1969-1984 and 1985-2003 103 Table 4.3.11 CHALK RIVER IDF Curves Temporal Trend Analyses Changes in IDF Curves for