To Theory of Tornado Formation: Mass Condensation Into Droplets, Their Polarization by the Earth Electric Fields and Rotation by Magnetic Field
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Fire-Modified Meteorology in a Coupled Fire–Atmosphere Model
704 JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY VOLUME 54 Fire-Modified Meteorology in a Coupled Fire–Atmosphere Model MIKA PEACE Bushfire Cooperative Research Centre, Melbourne, Victoria, and Applied Mathematics, Adelaide University, and Bureau of Meteorology, Adelaide, South Australia, Australia TRENT MATTNER AND GRAHAM MILLS Applied Mathematics, Adelaide University, South Australia, Australia JEFFREY KEPERT Bureau of Meteorology, Adelaide, South Australia, and Bushfire Cooperative Research Centre, Melbourne, Victoria, Australia LACHLAN MCCAW Department of Parks and Wildlife, Manjimup, Western Australia, Australia (Manuscript received 19 March 2014, in final form 27 November 2014) ABSTRACT The coupled fire–atmosphere model consisting of the Weather and Forecasting (WRF) Model coupled with the fire-spread model (SFIRE) module has been used to simulate a bushfire at D’Estrees Bay on Kangaroo Island, South Australia, in December 2007. Initial conditions for the simulations were provided by two global analyses: the GFS operational analysis and ERA-Interim. For each NWP initialization, the simulations were run with and without feedback from the fire to the atmospheric model. The focus of this study was examining how the energy fluxes from the simulated fire modified the local meteorological environment. With feedback enabled, the propagation speed of the sea-breeze frontal line was faster and vertical motion in the frontal zone was enhanced. For one of the initial conditions with feedback on, a vortex developed adjacent to the head fire and remained present for over 5 h of simulation time. The vortex was not present without fire–atmosphere feedback. The results show that the energy fluxes released by a fire can effect significant changes on the surrounding mesoscale atmosphere. -
2018 Natural Hazard Report 2018 Natural Hazard Report G January 2019
2018 Natural Hazard Report 2018 Natural Hazard Report g January 2019 Executive Summary 2018 was an eventful year worldwide. Wildfires scorched the West Coast of the United States; Hurricanes Michael and Florence battered the Gulf and East Coast. Typhoons and cyclones alike devastated the Philippines, Hong Kong, Japan and Oman. Earthquakes caused mass casualties in Indonesia, business interruption in Japan and structure damage in Alaska. Volcanoes made the news in Hawaii, expanding the island’s terrain. 1,000-year flood events (or floods that are said statistically to have a 1 in 1,000 chance of occurring) took place in Maryland, North Carolina, South Carolina, Texas and Wisconsin once again. Severe convective storms pelted Dallas, Texas, and Colorado Springs, Colorado, with large hail while a rash of tornado outbreaks, spawning 82 tornadoes in total, occurred from Western Louisiana and Arkansas all the way down to Southern Florida and up to Western Virginia. According to the National Oceanic and Atmospheric Administration (NOAA)1, there were 11 weather and climate disaster events with losses exceeding $1 billion in the U.S. Although last year’s count of billion- dollar events is a decrease from the previous year, both 2017 and 2018 have tracked far above the 1980- 2017 annual average of $6 billion events. In this report, CoreLogic® takes stock of the 2018 events to protect homeowners and businesses from the financial devastation that often follows catastrophe. No one can stop a hurricane in its tracks or steady the ground from an earthquake, but with more information and an understanding of the risk, recovery can be accelerated and resiliency can be attained. -
TWISTER TWISTER : Also Known As Tornado Or Cyclone
TWISTER TWISTER : Also known as Tornado or Cyclone. It is a violently rotating column of air that is in contact with both the surface of the earth and thunderstorm cloud. The term Tornado or Twister refers to the vortex of wind, not the condensation cloud. It comes in many shapes and sizes, but they are typically in the form of a visible condensation funnel, whose Wind of Twister narrow end touches the earth and is often encircled by debris and dust. Most tornadoes have wind speed less than 180km/h, are about 75m across, and travel several kilometers before dissipating. Twister Stretch The most extreme tornadoes can attain wind speed of more than 500km/h,stretch more than 3km across, and stay on the ground for more than 100km. HOW A TWISTER FORMS : Tornadoes are among the most violent storms on Earth, with the potential to cause very serious damage. Step 1 : Step 2 : Tornadoes needs certain When the warm, moist air meet Cold, Heat condition to form - particularly cold dry air, it explodes upwards, Dry Air very intense or unseasonable puncturing the layer above. A heat. Warm, thunder cloud may begin to build. Warm, Due to this heat, the ground Moist Air A storm quickly develops - there Moist Air temperature increases; the may be rain, thunder and moist air heats and starts to rise. Courtesy by - BBC News lightning. Courtesy by - BBC News Step 3 : Step 4 : Upward movement of air can The vortex of winds varies in become very rapid. Winds from size and shape, and can be different directions cause it to hundreds of meters wide. -
An Examination of the Mesoscale Environment of the James Island Memorial Day Tornado
19.6 AN EXAMINATION OF THE MESOSCALE ENVIRONMENT OF THE JAMES ISLAND MEMORIAL DAY TORNADO STEVEN B. TAYLOR NOAA/NATIONAL WEATHER SERVICE FORECAST OFFICE CHARLESTON, SC 1. INTRODUCTION conditions also induced weak cyclogenesis along the front near the vicinity of KVDI. By 1200 UTC A cluster of severe thunderstorms the surface low was located between KNBC and moved across portions of south coastal South KCHS. This low and its influences on the Carolina during the early morning hours of 30 kinematic environment as well as the eventual May 2006. Around 1135 UTC, a severe position of the surface frontal boundary will prove thunderstorm spawned an F-1 tornado in the to be the main contributing factors leading to the James Island community of Charleston, SC. The development of the James Island tornado. tornado produced wind and structural damage as it moved rapidly NE through several residential neighborhoods. The tornado was on the ground for approximately 0.1 mi before it emerged into the Atlantic Ocean as a large waterspout near the entrance to the Charleston Harbor. Timely tornado warnings were issued by the NOAA/National Weather Service Forecast Office (WFO) in Charleston, SC (CHS), despite the event occurring during a climatologically rare time of day. This study will concentrate on the mesoscale factors that supported the genesis of the tornado and its parent severe thunderstorm. Radar data generated by the KCLX WSR-88D will also be presented. 2. SYNOPTIC ENVIRONMENT The synoptic environment supported the development of scattered convective precipitation Fig 1. Map of eastern SC/GA across much of the coastal areas of the Carolinas and Georgia. -
Review of Vortices in Wildland Fire
Hindawi Publishing Corporation Journal of Combustion Volume 2011, Article ID 984363, 14 pages doi:10.1155/2011/984363 Review Article Review of Vortices in Wildland Fire Jason M. Forthofer1 and Scott L. Goodrick2 1 Rocky Mountain Research Station, USDA Forest Service, 5775 W US Highway 10, Missoula, MT 59808, USA 2 Southern Research Station, USDA Forest Service, 320 Green Street, Athens, GA 30602, USA Correspondence should be addressed to Jason M. Forthofer, [email protected] Received 30 December 2010; Accepted 15 March 2011 Academic Editor: D. Morvan Copyright © 2011 J. M. Forthofer and S. L. Goodrick. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Vortices are almost always present in the wildland fire environment and can sometimes interact with the fire in unpredictable ways, causing extreme fire behavior and safety concerns. In this paper, the current state of knowledge of the interaction of wildland fire and vortices is examined and reviewed. A basic introduction to vorticity is given, and the two common vortex forms in wildland fire are analyzed: fire whirls and horizontal roll vortices. Attention is given to mechanisms of formation and growth and how this information can be used by firefighters. 1. Introduction 2. Vorticity Basics Large fire whirls are often one of the more spectacular aspects Simply stated, vorticity is the measure of spin about an of fire behavior. Flames flow across the ground like water axis. That axis can be vertical, as in the case of a fire whirl, feeding into the base of the vortex, the lowest thousand feet of or horizontal for a roll vortex, or somewhere in between. -
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. -
Synthesis of Knowledge of Extreme Fire Behavior: Volume I for Fire Managers
United States Department of Agriculture Synthesis of Knowledge of Forest Service Pacific Northwest Extreme Fire Behavior: Research Station General Technical Volume I for Fire Managers Report PNW-GTR-854 November 2011 Paul A. Werth, Brian E. Potter, Craig B. Clements, Mark A. Finney, Scott L. Goodrick, Martin E. Alexander, Miguel G. Cruz, Jason A. Forthofer, and Sara S. McAllister A SUMMARY OF KNOWLEDGE FROM THE The Forest Service of the U.S. Department of Agriculture is dedicated to the principle of multiple use management of the Nation’s forest resources for sustained yields of wood, water, forage, wildlife, and recreation. Through forestry research, cooperation with the States and private forest owners, and management of the national forests and national grasslands, it strives—as directed by Congress—to provide increasingly greater service to a growing Nation. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or part of an individual’s income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). -
The Effects of Diabatic Heating on Upper
THE EFFECTS OF DIABATIC HEATING ON UPPER- TROPOSPHERIC ANTICYCLOGENESIS by Ross A. Lazear A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science (Atmospheric and Oceanic Sciences) at the UNIVERSITY OF WISCONSIN - MADISON 2007 i Abstract The role of diabatic heating in the development and maintenance of persistent, upper- tropospheric, large-scale anticyclonic anomalies in the subtropics (subtropical gyres) and middle latitudes (blocking highs) is investigated from the perspective of potential vorticity (PV) non-conservation. The low PV within blocking anticyclones is related to condensational heating within strengthening upstream synoptic-scale systems. Additionally, the associated convective outflow from tropical cyclones (TCs) is shown to build upper- tropospheric, subtropical anticyclones. Not only do both of these large-scale flow phenomena have an impact on the structure and dynamics of neighboring weather systems, and consequently the day-to-day weather, the very persistence of these anticyclones means that they have a profound influence on the seasonal climate of the regions in which they exist. A blocking index based on the meridional reversal of potential temperature on the dynamic tropopause is used to identify cases of wintertime blocking in the North Atlantic from 2000-2007. Two specific cases of blocking are analyzed, one event from February 1983, and another identified using the index, from January 2007. Parallel numerical simulations of these blocking events, differing only in one simulation’s neglect of the effects of latent heating of condensation (a “fake dry” run), illustrate the importance of latent heating in the amplification and wave-breaking of both blocking events. -
NCAR Annual Scientific Report Fiscal Year 1985 - Link Page Next PART0002
National Center for Atmospheric Research Annual Scientific Report Fiscal Year 1985 Submitted to National Science Foundation by University Corporation for Atmospheric Research March 1986 iii CONTENTS INTRODUCTION ............... ............................................. v ATMOSPHERIC ANALYSIS AND PREDICTION DIVISION ............... 1 Significant Accomplishments........................ 1 AAP Division Office................................................ 4 Mesoscale Research Section . ........................................ 8 Climate Section........................................ 15 Large-Scale Dynamics Section....................................... 22 Oceanography Section. .......................... 28 ATMOSPHERIC CHEMISTRY DIVISION................................. .. 37 Significant Accompl i shments........................................ 38 Precipitation Chemistry, Reactive Gases, and Aerosols Section. ..................................39 Atmospheric Gas Measurements Section............................... 46 Global Observations, Modeling, and Optical Techniques Section.............................. 52 Support Section.................................................... 57 Di rector' s Office. * . ...... .......... .. .. ** 58 HIGH ALTITUDE OBSERVATORYY .. .................. ............... 63 Significant Accomplishments .......... .............................. 63 Coronal/Interplanetary Physics Section ....................... 64 Solar Variability and Terrestrial Interactions Section........................................... 72 Solar -
Near-Surface Vortex Structure in a Tornado and in a Sub-Tornado-Strength Convective-Storm Vortex Observed by a Mobile, W-Band Radar During VORTEX2
VOLUME 141 MONTHLY WEATHER REVIEW NOVEMBER 2013 Near-Surface Vortex Structure in a Tornado and in a Sub-Tornado-Strength Convective-Storm Vortex Observed by a Mobile, W-Band Radar during VORTEX2 ,1 # @ ROBIN L. TANAMACHI,* HOWARD B. BLUESTEIN, MING XUE,* WEN-CHAU LEE, & & @ KRZYSZTOF A. ORZEL, STEPHEN J. FRASIER, AND ROGER M. WAKIMOTO * Center for Analysis and Prediction of Storms, and School of Meteorology, University of Oklahoma, Norman, Oklahoma # School of Meteorology, University of Oklahoma, Norman, Oklahoma @ National Center for Atmospheric Research, Boulder, Colorado & Microwave Remote Sensing Laboratory, University of Massachusetts, Amherst, Amherst, Massachusetts (Manuscript received 14 November 2012, in final form 22 May 2013) ABSTRACT As part of the Second Verification of the Origins of Rotation in Tornadoes Experiment (VORTEX2) field campaign, a very high-resolution, mobile, W-band Doppler radar collected near-surface (#200 m AGL) observations in an EF-0 tornado near Tribune, Kansas, on 25 May 2010 and in sub-tornado-strength vortices near Prospect Valley, Colorado, on 26 May 2010. In the Tribune case, the tornado’s condensation funnel dissipated and then reformed after a 3-min gap. In the Prospect Valley case, no condensation funnel was observed, but evidence from the highest-resolution radars in the VORTEX2 fleet indicates multiple, sub-tornado-strength vortices near the surface, some with weak-echo holes accompanying Doppler velocity couplets. Using high-resolution Doppler radar data, the authors document the full life cycle of sub- tornado-strength vortex beneath a convective storm that previously produced tornadoes. The kinematic evolution of these vortices, from genesis to decay, is investigated via ground-based velocity track display (GBVTD) analysis of the W-band velocity data. -
Fish & Wildlife Branch Research Permit Environmental Condition
Fish & Wildlife Branch Research Permit Environmental Condition Standards Fish and Wildlife Branch Technical Report No. 2013-21 December 2013 Fish & Wildlife Branch Scientific Research Permit Environmental Condition Standards First Edition 2013 PUBLISHED BY: Fish and Wildlife Branch Ministry of Environment 3211 Albert Street Regina, Saskatchewan S4S 5W6 SUGGESTED CITATION FOR THIS MANUAL: Saskatchewan Ministry of Environment. 2013. Fish & Wildlife Branch scientific research permit environmental condition standards. Fish and Wildlife Branch Technical Report No. 2013-21. 3211 Albert Street, Regina, Saskatchewan. 60 pp. ACKNOWLEDGEMENTS: Fish & Wildlife Branch scientific research permit environmental condition standards: The Research Permit Process Renewal working group (Karyn Scalise, Sue McAdam, Ben Sawa, Jeff Keith and Ed Beveridge) compiled the information found in this document to provide necessary information regarding species protocol environmental condition parameters. COVER PHOTO CREDITS: http://www.freepik.com/free-vector/weather-icons-vector- graphic_596650.htm CONTENT PHOTO CREDITS: as referenced CONTACT: [email protected] COPYRIGHT Brand and product names mentioned in this document are trademarks or registered trademarks of their respective holders. Use of brand names does not constitute an endorsement. Except as noted, all illustrations are copyright 2013, Ministry of Environment. ii Contents Introduction ....................................................................................................................... -
Storm Spotting – Solidifying the Basics PROFESSOR PAUL SIRVATKA COLLEGE of DUPAGE METEOROLOGY Focus on Anticipating and Spotting
Storm Spotting – Solidifying the Basics PROFESSOR PAUL SIRVATKA COLLEGE OF DUPAGE METEOROLOGY HTTP://WEATHER.COD.EDU Focus on Anticipating and Spotting • What do you look for? • What will you actually see? • Can you identify what is going on with the storm? Is Gilbert married? Hmmmmm….rumor has it….. Its all about the updraft! Not that easy! • Various types of storms and storm structures. • A tornado is a “big sucky • Obscuration of important thing” and underneath the features make spotting updraft is where it forms. difficult. • So find the updraft! • The closer you are to a storm the more difficult it becomes to make these identifications. Conceptual models Reality is much harder. Basic Conceptual Model Sometimes its easy! North Central Illinois, 2-28-17 (Courtesy of Matt Piechota) Other times, not so much. Reality usually is far more complicated than our perfect pictures Rain Free Base Dusty Outflow More like reality SCUD Scattered Cumulus Under Deck Sigh...wall clouds! • Wall clouds help spotters identify where the updraft of a storm is • Wall clouds may or may not be present with tornadic storms • Wall clouds may be seen with any storm with an updraft • Wall clouds may or may not be rotating • Wall clouds may or may not result in tornadoes • Wall clouds should not be reported unless there is strong and easily observable rotation noted • When a clear slot is observed, a well written or transmitted report should say as much Characteristics of a Tornadic Wall Cloud • Surface-based inflow • Rapid vertical motion (scud-sucking) • Persistent • Persistent rotation Clear Slot • The key, however, is the development of a clear slot Prof.