Paul Sirvatka's Notes: Thunderstorms (Pdf)
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Comparing Historical and Modern Methods of Sea Surface Temperature
EGU Journal Logos (RGB) Open Access Open Access Open Access Advances in Annales Nonlinear Processes Geosciences Geophysicae in Geophysics Open Access Open Access Natural Hazards Natural Hazards and Earth System and Earth System Sciences Sciences Discussions Open Access Open Access Atmospheric Atmospheric Chemistry Chemistry and Physics and Physics Discussions Open Access Open Access Atmospheric Atmospheric Measurement Measurement Techniques Techniques Discussions Open Access Open Access Biogeosciences Biogeosciences Discussions Open Access Open Access Climate Climate of the Past of the Past Discussions Open Access Open Access Earth System Earth System Dynamics Dynamics Discussions Open Access Geoscientific Geoscientific Open Access Instrumentation Instrumentation Methods and Methods and Data Systems Data Systems Discussions Open Access Open Access Geoscientific Geoscientific Model Development Model Development Discussions Open Access Open Access Hydrology and Hydrology and Earth System Earth System Sciences Sciences Discussions Open Access Ocean Sci., 9, 683–694, 2013 Open Access www.ocean-sci.net/9/683/2013/ Ocean Science doi:10.5194/os-9-683-2013 Ocean Science Discussions © Author(s) 2013. CC Attribution 3.0 License. Open Access Open Access Solid Earth Solid Earth Discussions Comparing historical and modern methods of sea surface Open Access Open Access The Cryosphere The Cryosphere temperature measurement – Part 1: Review of methods, Discussions field comparisons and dataset adjustments J. B. R. Matthews School of Earth and Ocean Sciences, University of Victoria, Victoria, BC, Canada Correspondence to: J. B. R. Matthews ([email protected]) Received: 3 August 2012 – Published in Ocean Sci. Discuss.: 20 September 2012 Revised: 31 May 2013 – Accepted: 12 June 2013 – Published: 30 July 2013 Abstract. Sea surface temperature (SST) has been obtained 1 Introduction from a variety of different platforms, instruments and depths over the past 150 yr. -
A Study of Synoptic-Scale Tornado Regimes
Garner, J. M., 2013: A study of synoptic-scale tornado regimes. Electronic J. Severe Storms Meteor., 8 (3), 1–25. A Study of Synoptic-Scale Tornado Regimes JONATHAN M. GARNER NOAA/NWS/Storm Prediction Center, Norman, OK (Submitted 21 November 2012; in final form 06 August 2013) ABSTRACT The significant tornado parameter (STP) has been used by severe-thunderstorm forecasters since 2003 to identify environments favoring development of strong to violent tornadoes. The STP and its individual components of mixed-layer (ML) CAPE, 0–6-km bulk wind difference (BWD), 0–1-km storm-relative helicity (SRH), and ML lifted condensation level (LCL) have been calculated here using archived surface objective analysis data, and then examined during the period 2003−2010 over the central and eastern United States. These components then were compared and contrasted in order to distinguish between environmental characteristics analyzed for three different synoptic-cyclone regimes that produced significantly tornadic supercells: cold fronts, warm fronts, and drylines. Results show that MLCAPE contributes strongly to the dryline significant-tornado environment, while it was less pronounced in cold- frontal significant-tornado regimes. The 0–6-km BWD was found to contribute equally to all three significant tornado regimes, while 0–1-km SRH more strongly contributed to the cold-frontal significant- tornado environment than for the warm-frontal and dryline regimes. –––––––––––––––––––––––– 1. Background and motivation As detailed in Hobbs et al. (1996), synoptic- scale cyclones that foster tornado development Parameter-based and pattern-recognition evolve with time as they emerge over the central forecast techniques have been essential and eastern contiguous United States (hereafter, components of anticipating tornadoes in the CONUS). -
The Lagrange Torando During Vortex2. Part Ii: Photogrammetry Analysis of the Tornado Combined with Dual-Doppler Radar Data
6.3 THE LAGRANGE TORANDO DURING VORTEX2. PART II: PHOTOGRAMMETRY ANALYSIS OF THE TORNADO COMBINED WITH DUAL-DOPPLER RADAR DATA Nolan T. Atkins*, Roger M. Wakimoto#, Anthony McGee*, Rachel Ducharme*, and Joshua Wurman+ *Lyndon State College #National Center for Atmospheric Research +Center for Severe Weather Research Lyndonville, VT 05851 Boulder, CO 80305 Boulder, CO 80305 1. INTRODUCTION studies, however, that have related the velocity and reflectivity features observed in the radar data to Over the years, mobile ground-based and air- the visual characteristics of the condensation fun- borne Doppler radars have collected high-resolu- nel, debris cloud, and attendant surface damage tion data within the hook region of supercell (e.g., Bluestein et al. 1993, 1197, 204, 2007a&b; thunderstorms (e.g., Bluestein et al. 1993, 1997, Wakimoto et al. 2003; Rasmussen and Straka 2004, 2007a&b; Wurman and Gill 2000; Alexander 2007). and Wurman 2005; Wurman et al. 2007b&c). This paper is the second in a series that pre- These studies have revealed details of the low- sents analyses of a tornado that formed near level winds in and around tornadoes along with LaGrange, WY on 5 June 2009 during the Verifica- radar reflectivity features such as weak echo holes tion on the Origins of Rotation in Tornadoes Exper- and multiple high-reflectivity rings. There are few iment (VORTEX 2). VORTEX 2 (Wurman et al. 5 June, 2009 KCYS 88D 2002 UTC 2102 UTC 2202 UTC dBZ - 0.5° 100 Chugwater 100 50 75 Chugwater 75 330° 25 Goshen Co. 25 km 300° 50 Goshen Co. 25 60° KCYS 30° 30° 50 80 270° 10 25 40 55 dBZ 70 -45 -30 -15 0 15 30 45 ms-1 Fig. -
Skip Talbot Photography by Jennifer Brindley
STORM SPOTTING Skip Talbot SECRETS Photography by Jennifer Brindley Ubl and others Topics • Supercell Visualization • Radar Presentation • Structure Identification • Storm Properties • Walk Through Disclaimers • Attend spotter training • Your safety is more important than spotting, photos, video, or tornado reports Supercell Visualization Lemon and Doswell 1979 Supercell Visualization Supercell Visualization Photo: Chris Gullikson Supercell Visualization Photo: Chris Gullikson Anvil Anvil Backshear Mammatus Cumulonimbus Flanking Line Cloud Base Striations Precipitation Wall Cloud Precipitation-free Base Supercell Visualization Radar Presentation Classic Hook Echo Radar Presentation Android / iOS Android Windows GrLevel3 / GrLevel2 Radar Presentation Classic Hook Echo Radar Presentation Radar Presentation Radar Presentation Radar Presentation Storm Spotting Zoo • Bear’s Cage • Whale’s Mouth • Beaver Tail • Horseshoe • Ghost Train Base (Updraft Base) (Rain Free Base or RFB) Base (Updraft Base) (Rain Free Base or RFB) Base (Updraft Base) (Rain Free Base or RFB) Base (Updraft Base) (Rain Free Base or RFB) Base (Updraft Base) (Rain Free Base or RFB) Base (Updraft Base) (Rain Free Base or RFB) Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe Horseshoe - Cyclical supercell with multiple tornadoes HorseshoeHorseshoe HorseshoeHorseshoe Horseshoe Horseshoe – Anticyclonic Funnel Horseshoe Horseshoe – Anticyclonic Funnel Horseshoe - No Wall Cloud Horseshoe - No Wall Cloud -
Meteorology – Lecture 19
Meteorology – Lecture 19 Robert Fovell [email protected] 1 Important notes • These slides show some figures and videos prepared by Robert G. Fovell (RGF) for his “Meteorology” course, published by The Great Courses (TGC). Unless otherwise identified, they were created by RGF. • In some cases, the figures employed in the course video are different from what I present here, but these were the figures I provided to TGC at the time the course was taped. • These figures are intended to supplement the videos, in order to facilitate understanding of the concepts discussed in the course. These slide shows cannot, and are not intended to, replace the course itself and are not expected to be understandable in isolation. • Accordingly, these presentations do not represent a summary of each lecture, and neither do they contain each lecture’s full content. 2 Animations linked in the PowerPoint version of these slides may also be found here: http://people.atmos.ucla.edu/fovell/meteo/ 3 Mesoscale convective systems (MCSs) and drylines 4 This map shows a dryline that formed in Texas during April 2000. The dryline is indicated by unfilled half-circles in orange, pointing at the more moist air. We see little T contrast but very large TD change. Dew points drop from 68F to 29F -- huge decrease in humidity 5 Animation 6 Supercell thunderstorms 7 The secret ingredient for supercells is large amounts of vertical wind shear. CAPE is necessary but sufficient shear is essential. It is shear that makes the difference between an ordinary multicellular thunderstorm and the rotating supercell. The shear implies rotation. -
Mid-Latitude Dynamics and Atmospheric Rivers Session: Theory, Structure, Processes 1 Jason M
Mid-Latitude Dynamics and Atmospheric Rivers Session: Theory, Structure, Processes 1 Jason M. Cordeira Wednesday, 10 August 2016 Plymouth State University, CW3E/Scripps Contribution from: Heini Werni Peter Knippertz Harold Sodemann Andreas Stohl Francina Dominguez Huancui Hu 2016 International Atmospheric Rivers Conference 8–11 August 2016 Scripps Institution of Oceanography Objective and Outline Objective • What components of midlatitude circulation support formation and structure of atmospheric rivers? Outline • Part 1: ARs, midlatitude storm track, and cyclogenesis • Part 2: ARs, tropical moisture exports, and warm conveyor belt Objective and Outline Objective • What components of midlatitude circulation support formation and structure of atmospheric rivers? Outline • Part 1: ARs, midlatitude storm track, and cyclogenesis • Part 2: ARs, tropical moisture exports, and warm conveyor belt Mimic TPW (SSEC/Wisconsin) • Global water vapor distribution is concentrated at lower latitudes owing to warmer temperatures • Observations illustrate poleward extrusions of water vapor along “tropospheric rivers” or “atmospheric rivers” Zhu and Newell (MWR-1998) • >90% of meridional water vapor transports occurs along ARs • ARs part of midlatitude cyclones and move with storm track Climatology of Water Vapor Transport Global mean IVT 150 kg m−1 s−1 • ECMWF ERA Interim Reanalysis • Oct–Mar 99/00 to 08/09 (i.e., ten winters) • IVT calculated for isobaric layers between 1000 and 100 hPa Tropical–Extratropical Interactions Waugh and Fanutso (2003-JAS) Knippertz -
ESSENTIALS of METEOROLOGY (7Th Ed.) GLOSSARY
ESSENTIALS OF METEOROLOGY (7th ed.) GLOSSARY Chapter 1 Aerosols Tiny suspended solid particles (dust, smoke, etc.) or liquid droplets that enter the atmosphere from either natural or human (anthropogenic) sources, such as the burning of fossil fuels. Sulfur-containing fossil fuels, such as coal, produce sulfate aerosols. Air density The ratio of the mass of a substance to the volume occupied by it. Air density is usually expressed as g/cm3 or kg/m3. Also See Density. Air pressure The pressure exerted by the mass of air above a given point, usually expressed in millibars (mb), inches of (atmospheric mercury (Hg) or in hectopascals (hPa). pressure) Atmosphere The envelope of gases that surround a planet and are held to it by the planet's gravitational attraction. The earth's atmosphere is mainly nitrogen and oxygen. Carbon dioxide (CO2) A colorless, odorless gas whose concentration is about 0.039 percent (390 ppm) in a volume of air near sea level. It is a selective absorber of infrared radiation and, consequently, it is important in the earth's atmospheric greenhouse effect. Solid CO2 is called dry ice. Climate The accumulation of daily and seasonal weather events over a long period of time. Front The transition zone between two distinct air masses. Hurricane A tropical cyclone having winds in excess of 64 knots (74 mi/hr). Ionosphere An electrified region of the upper atmosphere where fairly large concentrations of ions and free electrons exist. Lapse rate The rate at which an atmospheric variable (usually temperature) decreases with height. (See Environmental lapse rate.) Mesosphere The atmospheric layer between the stratosphere and the thermosphere. -
Central Region Technical Attachment 95-08 Examination of an Apparent
CRH SSD APRIL 1995 CENTRAL REGION TECHNICAL ATTACHMENT 95-08 EXAMINATION OF AN APPARENT LANDSPOUT IN THE EASTERN BLACK HILLS OF WESTERN SOUTH DAKOTA David L. Hintz1 and Matthew J. Bunkers National Weather Service Office Rapid City, South Dakota 1. Abstract On June 29, 1994, an apparent landspout occurred in the Black Hills of South Dakota. This landspout exhibited most of the features characteristic of traditional landspouts documented in eastern Colorado. The landspout lasted 3 to 8 minutes, had a width of less than 20 m and a path of 1 to 3 km, produced estimated wind speeds of Fl intensity (33 to 50 m s1), and emanated from a towering cumulus (TCU) cloud located along a quasi-stationary convergencq/cyclonic shear zone. No radar echo was observed with this event; however, a supercell thunderstorm was located 80-100 km to the east. National Weather Service meteorologists surveyed the “very localized” damage area and ruled out the possibility of the landspout being related to microburst, gustnado, or dust devil activity, as winds away from the landspout were less than 3 m s1. The landspout apparently “detached” from the parent TCU and damaged a farm which resulted in $1,000 dollars in expenses. 2. Introduction During the late 1980’s and early 1990’s researchers documented a phe nomenon with subtle differences from traditional tornadoes and waterspouts, herein referred to as the landspout (Seargent 1994; Brady and Szoke 1988, 1989; Bluestein 1985). The term “landspout” was actually coined by Bluestein (I985)(in the formal literature) when he observed this type of vortex along an Oklahoma squall line. -
Severe Weather Forecasting Tip Sheet: WFO Louisville
Severe Weather Forecasting Tip Sheet: WFO Louisville Vertical Wind Shear & SRH Tornadic Supercells 0-6 km bulk shear > 40 kts – supercells Unstable warm sector air mass, with well-defined warm and cold fronts (i.e., strong extratropical cyclone) 0-6 km bulk shear 20-35 kts – organized multicells Strong mid and upper-level jet observed to dive southward into upper-level shortwave trough, then 0-6 km bulk shear < 10-20 kts – disorganized multicells rapidly exit the trough and cross into the warm sector air mass. 0-8 km bulk shear > 52 kts – long-lived supercells Pronounced upper-level divergence occurs on the nose and exit region of the jet. 0-3 km bulk shear > 30-40 kts – bowing thunderstorms A low-level jet forms in response to upper-level jet, which increases northward flux of moisture. SRH Intense northwest-southwest upper-level flow/strong southerly low-level flow creates a wind profile which 0-3 km SRH > 150 m2 s-2 = updraft rotation becomes more likely 2 -2 is very conducive for supercell development. Storms often exhibit rapid development along cold front, 0-3 km SRH > 300-400 m s = rotating updrafts and supercell development likely dryline, or pre-frontal convergence axis, and then move east into warm sector. BOTH 2 -2 Most intense tornadic supercells often occur in close proximity to where upper-level jet intersects low- 0-6 km shear < 35 kts with 0-3 km SRH > 150 m s – brief rotation but not persistent level jet, although tornadic supercells can occur north and south of upper jet as well. -
Investigating the Climate System Precipitationprecipitation “The Irrational Inquirer”
Educational Product Educators Grades 5–8 Investigating the Climate System PrecipitationPrecipitation “The Irrational Inquirer” PROBLEM-BASED CLASSROOM MODULES Responding to National Education Standards in: English Language Arts ◆ Geography ◆ Mathematics Science ◆ Social Studies Investigating the Climate System PrecipitationPrecipitation “The Irrational Inquirer” Authored by: CONTENTS Mary Cerullo, Resources in Science Education, South Portland, Maine Grade Levels; Time Required; Objectives; Disciplines Encompassed; Key Terms; Key Concepts . 2 Prepared by: Stacey Rudolph, Senior Science Prerequisite Knowledge . 3 Education Specialist, Institute for Global Environmental Strategies Additional Prerequisite Knowledge and Facts . 5 (IGES), Arlington, Virginia Suggested Reading/Resources . 5 John Theon, Former Program Scientist for NASA TRMM Part 1: How are rainfall rates measured? . 6 Editorial Assistance, Dan Stillman, Truth Revealed after 200 Years of Secrecy! Science Communications Specialist, Pre-Activity; Activity One; Activity Two; Institute for Global Environmental Activity Three; Extensions. 8 Strategies (IGES), Arlington, Virginia Graphic Design by: Part 2: How is the intensity and distribution Susie Duckworth Graphic Design & of rainfall determined? . 9 Illustration, Falls Church, Virginia Airplane Pilot or Movie Critic? Funded by: Activity One; Activity Two. 9 NASA TRMM Grant #NAG5-9641 Part 3: How can you study rain? . 10 Give us your feedback: Foreseeing the Future of Satellites! To provide feedback on the modules Activity One; Activity Two . 10 online, go to: Activity Three; Extensions . 11 https://ehb2.gsfc.nasa.gov/edcats/ educational_product Unit Extensions . 11 and click on “Investigating the Climate System.” Appendix A: Bibliography/Resources . 12 Appendix B: Assessment Rubrics & Answer Keys. 13 NOTE: This module was developed as part of the series “Investigating the Climate Appendix C: National Education Standards. -
Quasi-Linear Convective System Mesovorticies and Tornadoes
Quasi-Linear Convective System Mesovorticies and Tornadoes RYAN ALLISS & MATT HOFFMAN Meteorology Program, Iowa State University, Ames ABSTRACT Quasi-linear convective system are a common occurance in the spring and summer months and with them come the risk of them producing mesovorticies. These mesovorticies are small and compact and can cause isolated and concentrated areas of damage from high winds and in some cases can produce weak tornadoes. This paper analyzes how and when QLCSs and mesovorticies develop, how to identify a mesovortex using various tools from radar, and finally a look at how common is it for a QLCS to put spawn a tornado across the United States. 1. Introduction Quasi-linear convective systems, or squall lines, are a line of thunderstorms that are Supercells have always been most feared oriented linearly. Sometimes, these lines of when it has come to tornadoes and as they intense thunderstorms can feature a bowed out should be. However, quasi-linear convective systems can also cause tornadoes. Squall lines and bow echoes are also known to cause tornadoes as well as other forms of severe weather such as high winds, hail, and microbursts. These are powerful systems that can travel for hours and hundreds of miles, but the worst part is tornadoes in QLCSs are hard to forecast and can be highly dangerous for the public. Often times the supercells within the QLCS cause tornadoes to become rain wrapped, which are tornadoes that are surrounded by rain making them hard to see with the naked eye. This is why understanding QLCSs and how they can produce mesovortices that are capable of producing tornadoes is essential to forecasting these tornadic events that can be highly dangerous. -
Thor's Legions American Meteorological Society Historical Monograph Series the History of Meteorology: to 1800, by H
Thor's Legions American Meteorological Society Historical Monograph Series The History of Meteorology: to 1800, by H. Howard Frisinger (1977/1983) The Thermal Theory of Cyclones: A History of Meteorological Thought in the Nineteenth Century, by Gisela Kutzbach (1979) The History of American Weather (four volumes), by David M. Ludlum Early American Hurricanes - 1492-1870 (1963) Early American Tornadoes - 1586-1870 (1970) Early American Winters I - 1604-1820 (1966) Early American Winters II - 1821-1870 (1967) The Atmosphere - A Challenge: The Science of Jule Gregory Charney, edited by Richard S. Lindzen, Edward N. Lorenz, and George W Platzman (1990) Thor's Legions: Weather Support to the u.s. Air Force and Army - 1937-1987, by John F. Fuller (1990) Thor's Legions Weather Support to the U.S. Air Force and Army 1937-1987 John F. Fuller American Meteorological Society 45 Beacon Street Boston, Massachusetts 02108-3693 The views expressed in this book are those of the author and do not reflect the official policy or position of the Department of Defense or the United States Government. © Copyright 1990 by the American Meteorological Society. Permission to use figures, tables, and briefexcerpts from this monograph in scientific and educational works is hereby granted provided the source is acknowledged. All rights reserved. No part ofthis publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, elec tronic, mechanical, photocopying, recording, or otherwise, without the prior written permis sion ofthe publisher. ISBN 978-0-933876-88-0 ISBN 978-1-935704-14-0 (eBook) DOI 10.1007/978-1-935704-14-0 Softcover reprint of the hardcover 1st edition 1990 Library of Congress catalog card number 90-81187 Published by the American Meteorological Society, 45 Beacon Street, Boston, Massachusetts 02108-3693 Richard E.