Estimating Enhanced Fujita Scale Levels Based on Forest Damage Severity
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Community at the Center of the Storm | 87
ABSTRACT This article is based on a Community at the keynote presentation delivered at the Alabama Poverty Project Lifetime of Learning Summit at the University of Center of the Storm Montevallo on September 30, 2011. Conference organizers asked for the Marybeth Lima perspective of a survivor of a significant natural disaster, for information Before hurricane Katrina, I was steady and regarding Louisiana’s recovery from confident in my job as an associate professor in the hurricanes Katrina and Rita in the short- department of biological & agricultural engineering at and long-term, and for advice on re- LSU. I had been doing service-learning since 1998, building and recovery within the and I worked very closely with the staff from the framework of poverty eradication. This Center for Community Engagement, Learning and paper details the author’s experiences in Leadership, or CCELL. In working closely with CCELL and with my community, I had developed the LSU the 2005 hurricanes and lessons learned Community Playground Project. through subsequent community- I teach a required, first-year biological engagement efforts. engineering design course in which my students partner with local public elementary schools to work with the true experts at play, the children at the schools, to develop dream playground designs at those schools. My class consists of two to three sections of students, and each section is assigned a separate public school. College students work collaboratively in teams of three to four people with the elementary school students, teachers, and school administrators, and sometimes parents or school improvement teams, to develop playground designs. -
What Are We Doing with (Or To) the F-Scale?
5.6 What Are We Doing with (or to) the F-Scale? Daniel McCarthy, Joseph Schaefer and Roger Edwards NOAA/NWS Storm Prediction Center Norman, OK 1. Introduction Dr. T. Theodore Fujita developed the F- Scale, or Fujita Scale, in 1971 to provide a way to compare mesoscale windstorms by estimating the wind speed in hurricanes or tornadoes through an evaluation of the observed damage (Fujita 1971). Fujita grouped wind damage into six categories of increasing devastation (F0 through F5). Then for each damage class, he estimated the wind speed range capable of causing the damage. When deriving the scale, Fujita cunningly bridged the speeds between the Beaufort Scale (Huler 2005) used to estimate wind speeds through hurricane intensity and the Mach scale for near sonic speed winds. Fujita developed the following equation to estimate the wind speed associated with the damage produced by a tornado: Figure 1: Fujita's plot of how the F-Scale V = 14.1(F+2)3/2 connects with the Beaufort Scale and Mach number. From Fujita’s SMRP No. 91, 1971. where V is the speed in miles per hour, and F is the F-category of the damage. This Amazingly, the University of Oklahoma equation led to the graph devised by Fujita Doppler-On-Wheels measured up to 318 in Figure 1. mph flow some tens of meters above the ground in this tornado (Burgess et. al, 2002). Fujita and his staff used this scale to map out and analyze 148 tornadoes in the Super 2. Early Applications Tornado Outbreak of 3-4 April 1974. -
19.4 Updated Mobile Radar Climatology of Supercell
19.4 UPDATED MOBILE RADAR CLIMATOLOGY OF SUPERCELL TORNADO STRUCTURES AND DYNAMICS Curtis R. Alexander* and Joshua M. Wurman Center for Severe Weather Research, Boulder, Colorado 1. INTRODUCTION evolution of angular momentum and vorticity near the surface in many of the tornado cases is also High-resolution mobile radar observations of providing some insight into possible modes of supercell tornadoes have been collected by the scale contraction for tornadogenesis and failure. Doppler On Wheels (DOWs) platform between 1995 and present. The result of this ongoing effort 2. DATA is a large observational database spanning over 150 separate supercell tornadoes with a typical The DOWs have collected observations in and data resolution of O(50 m X 50 m X 50 m), near supercell tornadoes from 1995 through 2008 updates every O(60 s) and measurements within including the fields of Doppler velocity, received 20 m of the surface (Wurman et al. 1997; Wurman power, normalized coherent power, radar 1999, 2001). reflectivity, coherent reflectivity and spectral width (Wurman et al. 1997). Stemming from this database is a multi-tiered effort to characterize the structure and dynamics of A typical observation is a four-second quasi- the high wind speed environments in and near horizontal scan through a tornado vortex. To date supercell tornadoes. To this end, a suite of there have been over 10000 DOW observations of algorithms is applied to the radar tornado supercell tornadoes comprising over 150 individual observations for quality assurance along with tornadoes. detection, tracking and extraction of kinematic attributes. Data used for this study include DOW supercell tornado observations from 1995-2003 comprising The integration of observations across tornado about 5000 individual observations of 69 different cases in the database is providing an estimate of mesocyclone-associated tornadoes. -
Observations and Laboratory Simulations of Tornadoes in Complex Topographical Regions Christopher D
Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2012 Observations and Laboratory Simulations of Tornadoes in Complex Topographical Regions Christopher D. Karstens Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Atmospheric Sciences Commons, and the Meteorology Commons Recommended Citation Karstens, Christopher D., "Observations and Laboratory Simulations of Tornadoes in Complex Topographical Regions" (2012). Graduate Theses and Dissertations. 12778. https://lib.dr.iastate.edu/etd/12778 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Observations and laboratory simulations of tornadoes in complex topographical regions by Christopher Daniel Karstens A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major: Meteorology Program of Study Committee: William A. Gallus, Jr., Major Professor Partha P. Sarkar Bruce D. Lee Catherine A. Finley Raymond W. Arritt Xiaoqing Wu Iowa State University Ames, Iowa 2012 Copyright © Christopher Daniel Karstens, 2012. All rights reserved. ii TABLE OF CONTENTS LIST OF FIGURES .............................................................................................. -
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. -
The Year That Shook the Rich: a Review of Natural Disasters in 2011
THE YEAR THAT SHOOK THE RICH: A REVIEW OF NATURAL DISASTERS IN 2011 The Brookings Institution – London School of Economics Project on Internal Displacement March 2012 Design: [email protected] Cover photo: © Thinkstock.com Back cover photos: left / © Awcnz62 | Dreamstime.com; right / © IOM 2011 - MPK0622 (Photo: Chris Lom) THE YEAR THAT SHOOK THE RICH: A REVIEW OF NATURAL DISASTERS IN 2011 By Elizabeth Ferris and Daniel Petz March 2012 PUBLISHED BY: THE BROOKINGS INSTITUTION – LONDON SCHOOL OF ECONOMICS PROJECT ON INTERNAL DISPLACEMENT Bangkok, Thailand — Severe monsoon floods, starting in late July 2011, affected millions of people. A truck with passengers aboard drives through a heavily flooded street. Photo: UN/Mark Garten TABLE OF CONTENTS Acronyms ................................................................................................................................. vi Foreword ................................................................................................................................. ix Executive Summary ................................................................................................................. xi Introduction .............................................................................................................................. xv Chapter 1 The Year that Shook the Rich ...................................................... 1 Section 1 Disasters in the “Rich” World, Some Numbers ............................................ 5 Section 2 Japan: The Most Expensive Disaster -
A Background Investigation of Tornado Activity Across the Southern Cumberland Plateau Terrain System of Northeastern Alabama
DECEMBER 2018 L Y Z A A N D K N U P P 4261 A Background Investigation of Tornado Activity across the Southern Cumberland Plateau Terrain System of Northeastern Alabama ANTHONY W. LYZA AND KEVIN R. KNUPP Department of Atmospheric Science, Severe Weather Institute–Radar and Lightning Laboratories, Downloaded from http://journals.ametsoc.org/mwr/article-pdf/146/12/4261/4367919/mwr-d-18-0300_1.pdf by NOAA Central Library user on 29 July 2020 University of Alabama in Huntsville, Huntsville, Alabama (Manuscript received 23 August 2018, in final form 5 October 2018) ABSTRACT The effects of terrain on tornadoes are poorly understood. Efforts to understand terrain effects on tornadoes have been limited in scope, typically examining a small number of cases with limited observa- tions or idealized numerical simulations. This study evaluates an apparent tornado activity maximum across the Sand Mountain and Lookout Mountain plateaus of northeastern Alabama. These plateaus, separated by the narrow Wills Valley, span ;5000 km2 and were impacted by 79 tornadoes from 1992 to 2016. This area represents a relative regional statistical maximum in tornadogenesis, with a particular tendency for tornadogenesis on the northwestern side of Sand Mountain. This exploratory paper investigates storm behavior and possible physical explanations for this density of tornadogenesis events and tornadoes. Long-term surface observation datasets indicate that surface winds tend to be stronger and more backed atop Sand Mountain than over the adjacent Tennessee Valley, potentially indicative of changes in the low-level wind profile supportive to storm rotation. The surface data additionally indicate potentially lower lifting condensation levels over the plateaus versus the adjacent valleys, an attribute previously shown to be favorable for tornadogenesis. -
Estimating Wind Damage in Forested Areas Due to Tornadoes
Article Estimating Wind Damage in Forested Areas Due to Tornadoes Mohamed A. Mansour 1,2, Daniel M. Rhee 3, Timothy Newson 1,* , Chris Peterson 4 and Franklin T. Lombardo 3 1 Department of Civil and Environmental Engineering, Western University, London, ON N6A 5B9, Canada; [email protected] 2 Public Works Engineering Department, Cairo University, Giza 12613, Egypt 3 Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Champaign, IL 61801, USA; [email protected] (D.M.R.); [email protected] (F.T.L.) 4 Department of Plant Biology, University of Georgia, Athens, GA 30602, USA; [email protected] * Correspondence: [email protected]; Tel.: +1-519-850-2973 Abstract: Research Highlights: Simulations of treefall patterns during tornado events have been conducted, enabling the coupled effects of tornado characteristics, tree properties and soil conditions to be assessed for the first time. Background and Objectives: Treefall patterns and forest damage assessed in post-storm surveys are dependent on the interaction between topography, biology and meteorology, which makes identification of characteristic behavior challenging. Much of our knowledge of tree damage during extreme winds is based on synoptic storms. Better characterization of tree damage will provide more knowledge of tornado impacts on forests, as well as their ecological significance. Materials and Methods: a numerical method based on a Rankine vortex model coupled with two mechanistic tree models for critical wind velocity for stem break and windthrow was used to simulate tornadic tree damage. To calibrate the models, a treefall analysis of the Alonsa tornado was used. Parametric study was conducted to assess induced tornadic tree failure patterns for uprooting on saturated and unsaturated soils and stem break with different knot factors. -
Damage Analysis of Three Long-Track Tornadoes Using High-Resolution Satellite Imagery
atmosphere Article Damage Analysis of Three Long-Track Tornadoes Using High-Resolution Satellite Imagery Daniel Burow * , Hannah V. Herrero and Kelsey N. Ellis Department of Geography, University of Tennessee, Knoxville, 1000 Phil Fulmer Way, Knoxville, TN 37920, USA; [email protected] (H.V.H.); [email protected] (K.N.E.) * Correspondence: [email protected] Received: 2 May 2020; Accepted: 8 June 2020; Published: 10 June 2020 Abstract: Remote sensing of tornado damage can provide valuable observations for post-event surveys and reconstructions. The tornadoes of 3 March 2019 in the southeastern United States are an ideal opportunity to relate high-resolution satellite imagery of damage with estimated wind speeds from post-event surveys, as well as with the Rankine vortex tornado wind field model. Of the spectral metrics tested, the strongest correlations with survey-estimated wind speeds are found using a Normalized Difference Vegetation Index (NDVI, used as a proxy for vegetation health) difference image and a principal components analysis emphasizing differences in red and blue band reflectance. NDVI-differenced values across the width of the EF-4 Beauregard-Smiths Station, Alabama, tornado path resemble the pattern of maximum ground-relative wind speeds across the width of the Rankine vortex model. Maximum damage sampled using these techniques occurred within 130 m of the tornado vortex center. The findings presented herein establish the utility of widely accessible Sentinel imagery, which is shown to have sufficient spatial resolution to make inferences about the intensity and dynamics of violent tornadoes occurring in vegetated areas. Keywords: tornadoes; tornado damage; remote sensing; Sentinel-2; NDVI; PCA; Rankine vortex 1. -
The Enhanced Fujita Tornado Scale
NCDC: Educational Topics: Enhanced Fujita Scale Page 1 of 3 DOC NOAA NESDIS NCDC > > > Search Field: Search NCDC Education / EF Tornado Scale / Tornado Climatology / Search NCDC The Enhanced Fujita Tornado Scale Wind speeds in tornadoes range from values below that of weak hurricane speeds to more than 300 miles per hour! Unlike hurricanes, which produce wind speeds of generally lesser values over relatively widespread areas (when compared to tornadoes), the maximum winds in tornadoes are often confined to extremely small areas and can vary tremendously over very short distances, even within the funnel itself. The tales of complete destruction of one house next to one that is totally undamaged are true and well-documented. The Original Fujita Tornado Scale In 1971, Dr. T. Theodore Fujita of the University of Chicago devised a six-category scale to classify U.S. tornadoes into six damage categories, called F0-F5. F0 describes the weakest tornadoes and F5 describes only the most destructive tornadoes. The Fujita tornado scale (or the "F-scale") has subsequently become the definitive scale for estimating wind speeds within tornadoes based upon the damage caused by the tornado. It is used extensively by the National Weather Service in investigating tornadoes, by scientists studying the behavior and climatology of tornadoes, and by engineers correlating damage to different types of structures with different estimated tornado wind speeds. The original Fujita scale bridges the gap between the Beaufort Wind Speed Scale and Mach numbers (ratio of the speed of an object to the speed of sound) by connecting Beaufort Force 12 with Mach 1 in twelve steps. -
On the Implementation of the Enhanced Fujita Scale in the USA
Atmospheric Research 93 (2009) 554–563 Contents lists available at ScienceDirect Atmospheric Research journal homepage: www.elsevier.com/locate/atmos On the implementation of the enhanced Fujita scale in the USA Charles A. Doswell III a,⁎, Harold E. Brooks b, Nikolai Dotzek c,d a Cooperative Institute for Mesoscale Meteorological Studies, National Weather Center, 120 David L. Boren Blvd., Norman, OK 73072, USA b NOAA/National Severe Storms Laboratory, National Weather Center, 120 David L. Boren Blvd., Norman, OK 73072, USA c Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, 82234 Wessling, Germany d European Severe Storms Laboratory (ESSL), Münchner Str. 20, 82234 Wessling, Germany article info abstract Article history: The history of tornado intensity rating in the United States of America (USA), pioneered by Received 1 December 2007 T. Fujita, is reviewed, showing that non-meteorological changes in the climatology of the Received in revised form 5 November 2008 tornado intensity ratings are likely, raising questions about the temporal (and spatial) Accepted 14 November 2008 consistency of the ratings. Although the Fujita scale (F-scale) originally was formulated as a peak wind speed scale for tornadoes, it necessarily has been implemented using damage to Keywords: estimate the wind speed. Complexities of the damage-wind speed relationship are discussed. Tornado Recently, the Fujita scale has been replaced in the USA as the official system for rating tornado F-scale intensity by the so-called Enhanced Fujita scale (EF-scale). Several features of the new rating EF-scale Intensity distribution system are reviewed and discussed in the context of a proposed set of desirable features of a tornado intensity rating system. -
Can Elevation Be Associated with the 2011 Joplin, Missouri, Tornado
aphy & N r at Stimers and Paul, J Geogr Nat Disast 2017, 7:2 og u e ra l G f D DOI: 10.4172/2167-0587.1000202 o i s l a Journal of a s n t r e u r s o J ISSN: 2167-0587 Geography & Natural Disasters ResearchReview Article Article Open Access Can Elevation be Associated with the 2011 Joplin, Missouri, Tornado Fatalities? An Empirical Study Mitchel Stimers* and Bimal Kanti Paul Department of Natural and Physical Sciences, Cloud County Community College, Junction City, Kansas, 66441, USA Abstract The 2011 Joplin, MO, USA, tornado set a record in terms of the number of lives lost-no other tornado in the United States had killed as many as 161 people since 1950. There are many stochastic parameters that can affect the speed, direction, and magnitude of a tornado and it is thought that elevation may play a role in tornado intensity. The Joplin tornado created a track whose elevation was approximately 50 m from beginning to end, providing the impetus to examine whether or not the elevation change over the damage path tornado is associated with fatalities that resulted from the event. Using data collected from various sources, and the application of GIS as well as non-parametric statistics, we reveal that the elevation and tornado fatalities are inversely related, however; the relationship is not statistically significant, the reasons for which are discussed. Keywords: Joplin tornado; Tornado fatalities; Elevation; Damage Dating to 1950, when official tabulation began, no other tornado zone; GIS in the US had killed as many people as the Joplin event.