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Research.Pdf (4.154Mb) The Relationship between Mid-West Precipitation Rates, Teleconnections and Blocking in the Eastern and Central Pacific ______________________________________ A Thesis Presented to the Faculty of the Graduate School at the University of Missouri ___________________________________________________________ In Partial Fulfillment of the Requirements for the Degree Masters of Science _______________________________________ by JORDAN RABINOWITZ Dr. Anthony Lupo, Thesis Advisor December 2016 The Relationship between Mid-West Precipitation Rates, Teleconnections and Blocking in the Eastern and Central Pacific A Thesis Presented to the Faculty of the Graduate School at the University of Missouri In Partial Fulfillment of the Requirements for the Degree Masters of Science Presented by Jordan Rabinowitz, a candidate for the degree of master of science, and hereby certify that, in their opinion, it is worthy of acceptance. Professor Anthony Lupo, Thesis Advisor ____________________________________________ Professor John Sadler ____________________________________________ Professor Patrick Market ____________________________________________ Associate Professor Patrick Guinan ____________________________________________ Professor Allen Thompson ____________________________________________ Acknowledgements First and foremost, I would like to thank my advisor Dr. Anthony Lupo who has truly been an inspiration to me throughout my time at the University of Missouri. It has truly been a privilege to have an advisor who cares so much about his students and is so consistently determined to facilitate paths to success. In addition to being a professor and advisor, Dr. Lupo has been a close friend who has instilled many great life-long lessons and has fostered an enriched appreciation for studying the ocean-atmosphere system. I would also like to thank Dr. John Sadler who played an integral role in assisting me to learn and code with the R coding language. Dr. Sadler also provided incredibly helpful advice about research analysis approaches and numerous invaluable life lessons while working through a variety of different data analyses during the first year of my M.S. program. In addition, I am incredibly grateful for his role in getting the Agricultural Research Service Division of the United States Department of Agriculture to fund my 2- year M.S. research assistantship. In addition, I would like to thank Dr. Market, Dr. Thompson, and Dr. Guinan for their very helpful and insightful advice through my research. Next, I would like to sincerely thank my parents who have been there for me every step of the way and have helped give unconditional emotional support to my endeavors which I am eternally grateful for. I would also like to thank my family and friends who have consistently given genuine, loving support through the good and the more challenging days. All this emotional support helped to guide me since moving out to central Missouri in pursuit of my M.S. degree. I could not have asked for a better series of opportunities and am eternally grateful for the truly incredible accomplishments I have been able to achieve thus far. ii Table of Contents Acknowledgements………….............……………………………………………….......ii Abstract………………………………………………….................…………………...vii Chapter 1: Introduction…………………………………………………………….........1-4 1.1 Purpose………………………………………………………………………...4 1.2 Objective…………………………….…………………………….………...4-5 Chapter 2: Methodology……………………………………………………………….5-12 Chapter 3: Interannual and Interdecadal Variability……………………………………….. 3.1: El Niño Southern Oscillation Background…………………….…......12-16 3.2: El Niño Event Analyses…………………………………………….........16-29 3.3: La Niña Event Analyses……………..…………………………………..29-39 3.4: Neutral-ENSO Event Analyses………………………..………………...39-55 3.5: Investigation of PDO Influences........…………………………………...56-61 3.6: Impacts of Climate Change on Heavy Rainfall Statistics……………………... 3.6.1: Climate Change Assessment Background Information.……61-62 3.6.2: ENSO/PDO Statistical Analysis………...……………………..62-67 3.6.3: Climate Change Assessment ENSO/PDO Rainfall Rate Analysis for Events with Rainfall Totals of ≥ 2.50 Inches (63.5 mm)…...…….67-70 3.6.4: Climate Change Assessment ENSO/PDO Rainfall Rate Analysis for Events with Rainfall Totals of ≥ 3.00 Inches (76.2 mm)…………70-72 3.6.5: Climate Change Assessment Evaluation of Statistical Significance (Results, Discussion, and Operational Implications)…...72-78 Chapter 4: USDA-ARS Research Results and Implications……………………………..78 4.1: Implications of Interannual and Interdecadal Variability…………………...79 iii 4.2: Implications of Atmospheric Rivers and Blocking Events……………...79-81 4.3: Implications of Upper-Air Sounding Characteristics…………………....81-82 Chapter 5: Impacts of Atmospheric Rivers….……………………………………………... 5.1: Atmospheric Rivers Background……………………………….........82-83 5.2: Atmospheric Rivers AR Analysis Context Breakdown……………...83-85 5.3: Atmospheric Rivers AR Intensity Statistical Analysis………….........85-86 5.4: Atmospheric Rivers AR Duration Statistical Analysis…………........86-88 5.5: AR Intensity/Duration Coupled Statistical Analysis Results………...88-89 5.6: Atmospheric Rivers AR Intensity ENSO-Based Analysis…………...89-90 5.7: Atmospheric Rivers AR Duration ENSO-Based Analysis…………...90-91 5.8: HYSPLIT Model………………………………………………………………. 5.8.1: HYSPLIT Air Parcel Trajectory Model Background………….92 5.8.2: HYSPLIT Backward Air Parcel Trajectories El Niño Events…… .……………………………………………………………………….93-95 5.8.3: HYSPLIT Air Parcel Trajectories La Niña Events………...95-96 5.8.4: HYSPLIT Air Parcel Trajectories Neutral-ENSO Events.....96-99 5.9: Atmospheric Rivers Precipitable Water Analyses…………………………. 5.9.1: Precipitable Water Analyses Background………………...99-100 5.9.2: Precipitable Water Analyses El Niño Events……………100-101 5.9.3: Precipitable Water Analyses La Niña Events…………....101-103 5.9.4: Precipitable Water Analyses Neutral-ENSO Events….....104-106 5.10: Tropical Atlantic Sea-Surface Temperatures (SST) Analyses………107-108 5.10.1: Tropical Atlantic SST Analyses ENSO-Based Analysis……….109 Chapter 6 Impacts of Atmospheric Blocking…………..………………………….109-110 6.1: Atmospheric Blocking Background Information………………….110-111 iv 6.2: Atmospheric Blocking Blocking Parameter Details……………….111-114 6.3: Blocking Intensity Statistical and ENSO-Based Analysis………...115-117 6.4: Blocking Duration Statistical and ENSO-Based Analysis………...117-119 6.5: Blocking Size Statistical and ENSO-Based Analysis……………..119-121 6.6: Blocking Onset Lead Time Statistical and ENSO-Based Analysis……………………………………………………………………121-122 6.7: Longitude at Blocking Onset Statistical and ENSO-Based Analysis........................................................................................................123-125 6.8: Effects of Atmospheric Blocking Influence on AR Landfalls…….125-129 6.9: Atmospheric Blocking Monthly Event Frequency Breakdown…...129-133 Chapter 7 Upper-Air Sounding Analyses…...………………………………………........... 7.1: Upper-Air Sounding Analyses Background Information………….133-136 7.2: Upper-Air Sounding Analyses Sounding Parameters……..………137-142 7.3: Upper-Air Sounding Analyses Atmospheric Thermodynamics…...142-143 7.4: Surface-Based CAPE Statistical and ENSO-Based Analyses………….144 7.5: Mixed-Layer CAPE Statistical and ENSO-Based Analyses………145-148 7.6: Surface-Based Convective Inhibition Statistical and ENSO-Based Analyses……………………………………………………………………148-149 7.7: Mixed-Layer Convective Inhibition Statistical/ENSO-Based…......149-150 7.8: Lifting Condensation Level Statistical and ENSO-Based Analyses …………………………………………………………..............................150-155 7.9: Level of Free Convection Statistical and ENSO-Based Analyses...155-159 7.10: Vertical Wind Profiles Statistical Analysis………………………159-160 7.11: Vertical Wind Profiles ENSO-Based Analysis…………………..160-161 7.12: Temperature and Dew Point Profile Composite Analyses…………..161-162 7.12.1: Temperature/Dew Point Profiles: Monthly Analysis……...162-164 7.12.2: Temperature/Dew Point Profiles: ENSO-Based Analysis...164-165 v Chapter 8 Conclusions……………………………………………………………………………........ 8.1: Interannual and Interdecadal Variability……………………………...166-167 8.2: Atmospheric Rivers…………………………………………………...167-168 8.3: Atmospheric Blocking………………………………………………...168-169 8.4: Upper-Air Soundings………………………………………………….170-171 References…………………………………………………………………………172-178 Figures……………………………………………………………………………..179-236 Tables…………………………………………………………………………........237-238 vi Abstract An integral aspect of accurate precipitation outlooks are timely forecasts of teleconnective phase transitions (i.e., the El Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO)). Through executing comprehensive synoptic analyses of twenty-seven rainfall events between 2000 and 2014, results should bolster the integration of climatic signals in forecasting. An integral part of this work is evaluating characteristics of the dominant synoptic modes: low pressure systems (i.e., extra-tropical cyclones or shortwave troughs), tropical cyclones, and quasi-stationary frontal boundaries. Other studied parameters include: 300-mb height and divergence, 400 to 250-mb potential vorticity coupled with potential vorticity advection and 300-mb streamlines, 500-mb height and absolute vorticity coupled with 700 to 400-mb differential vorticity advection, 850-mb height/moisture transport/Θe, and precipitable water. Lastly, synoptic analyses were conducted for every event at 250 mb, 300 mb, 500 mb, 700 mb,
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