Some Basic Elements of Thunderstorm Forecasting
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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. -
3. Electrical Structure of Thunderstorm Clouds
3. Electrical Structure of Thunderstorm Clouds 1 Cloud Charge Structure and Mechanisms of Cloud Electrification An isolated thundercloud in the central New Mexico, with rudimentary indication of how electric charge is thought to be distributed and around the thundercloud, as inferred from the remote and in situ observations. Adapted from Krehbiel (1986). 2 2 Cloud Charge Structure and Mechanisms of Cloud Electrification A vertical tripole representing the idealized gross charge structure of a thundercloud. The negative screening layer charges at the cloud top and the positive corona space charge produced at ground are ignored here. 3 3 Cloud Charge Structure and Mechanisms of Cloud Electrification E = 2 E (−)cos( 90o−α) Q H = 2 2 3/2 2πεo()H + r sinα = k Q = const R2 ( ) Method of images for finding the electric field due to a negative point charge above a perfectly conducting ground at a field point located at the ground surface. 4 4 Cloud Charge Structure and Mechanisms of Cloud Electrification The electric field at ground due to the vertical tripole, labeled “Total”, as a function of the distance from the axis of the tripole. Also shown are the contributions to the total electric field from the three individual charges of the tripole. An upward directed electric field is defined as positive (according to the physics sign convention). 5 5 Cloud Charge Structure and Mechanisms of Cloud Electrification Electric Field Change Due to Negative Cloud-to-Ground Discharge Electric Field Change Due to a Cloud Discharge Electric Field Change, kV/m Change, Electric Field Electric Field Change, kV/m Change, Electric Field Distance, km Distance, km Electric field change at ground, due to the Electric field change at ground, due to the total removal of the negative charge of the total removal of the negative and upper vertical tripole via a cloud-to-ground positive charges of the vertical tripole via a discharge, as a function of distance from cloud discharge, as a function of distance from the axis of the tripole. -
Soaring Weather
Chapter 16 SOARING WEATHER While horse racing may be the "Sport of Kings," of the craft depends on the weather and the skill soaring may be considered the "King of Sports." of the pilot. Forward thrust comes from gliding Soaring bears the relationship to flying that sailing downward relative to the air the same as thrust bears to power boating. Soaring has made notable is developed in a power-off glide by a conven contributions to meteorology. For example, soar tional aircraft. Therefore, to gain or maintain ing pilots have probed thunderstorms and moun altitude, the soaring pilot must rely on upward tain waves with findings that have made flying motion of the air. safer for all pilots. However, soaring is primarily To a sailplane pilot, "lift" means the rate of recreational. climb he can achieve in an up-current, while "sink" A sailplane must have auxiliary power to be denotes his rate of descent in a downdraft or in come airborne such as a winch, a ground tow, or neutral air. "Zero sink" means that upward cur a tow by a powered aircraft. Once the sailcraft is rents are just strong enough to enable him to hold airborne and the tow cable released, performance altitude but not to climb. Sailplanes are highly 171 r efficient machines; a sink rate of a mere 2 feet per second. There is no point in trying to soar until second provides an airspeed of about 40 knots, and weather conditions favor vertical speeds greater a sink rate of 6 feet per second gives an airspeed than the minimum sink rate of the aircraft. -
Cloud Characteristics, Thermodynamic Controls and Radiative Impacts During the Observations and Modeling of the Green Ocean Amazon (Goamazon2014/5) Experiment
Atmos. Chem. Phys., 17, 14519–14541, 2017 https://doi.org/10.5194/acp-17-14519-2017 © Author(s) 2017. This work is distributed under the Creative Commons Attribution 3.0 License. Cloud characteristics, thermodynamic controls and radiative impacts during the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) experiment Scott E. Giangrande1, Zhe Feng2, Michael P. Jensen1, Jennifer M. Comstock1, Karen L. Johnson1, Tami Toto1, Meng Wang1, Casey Burleyson2, Nitin Bharadwaj2, Fan Mei2, Luiz A. T. Machado3, Antonio O. Manzi4, Shaocheng Xie5, Shuaiqi Tang5, Maria Assuncao F. Silva Dias6, Rodrigo A. F de Souza7, Courtney Schumacher8, and Scot T. Martin9 1Environmental and Climate Sciences Department, Brookhaven National Laboratory, Upton, NY, USA 2Pacific Northwest National Laboratory, Richland, WA, USA 3National Institute for Space Research, São José dos Campos, Brazil 4National Institute of Amazonian Research, Manaus, Amazonas, Brazil 5Lawrence Livermore National Laboratory, Livermore, CA, USA 6University of São Paulo, São Paulo, Department of Atmospheric Sciences, Brazil 7State University of Amazonas (UEA), Meteorology, Manaus, Brazil 8Texas A&M University, College Station, Department of Atmospheric Sciences, TX, USA 9Harvard University, Cambridge, School of Engineering and Applied Sciences and Department of Earth and Planetary Sciences, MA, USA Correspondence to: Scott E. Giangrande ([email protected]) Received: 12 May 2017 – Discussion started: 24 May 2017 Revised: 30 August 2017 – Accepted: 11 September 2017 – Published: 6 December 2017 Abstract. Routine cloud, precipitation and thermodynamic 1 Introduction observations collected by the Atmospheric Radiation Mea- surement (ARM) Mobile Facility (AMF) and Aerial Facility The simulation of clouds and the representation of cloud (AAF) during the 2-year US Department of Energy (DOE) processes and associated feedbacks in global climate mod- ARM Observations and Modeling of the Green Ocean Ama- els (GCMs) remains the largest source of uncertainty in zon (GoAmazon2014/5) campaign are summarized. -
Climatic Information of Western Sahel F
Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Clim. Past Discuss., 10, 3877–3900, 2014 www.clim-past-discuss.net/10/3877/2014/ doi:10.5194/cpd-10-3877-2014 CPD © Author(s) 2014. CC Attribution 3.0 License. 10, 3877–3900, 2014 This discussion paper is/has been under review for the journal Climate of the Past (CP). Climatic information Please refer to the corresponding final paper in CP if available. of Western Sahel V. Millán and Climatic information of Western Sahel F. S. Rodrigo (1535–1793 AD) in original documentary sources Title Page Abstract Introduction V. Millán and F. S. Rodrigo Conclusions References Department of Applied Physics, University of Almería, Carretera de San Urbano, s/n, 04120, Almería, Spain Tables Figures Received: 11 September 2014 – Accepted: 12 September 2014 – Published: 26 September J I 2014 Correspondence to: F. S. Rodrigo ([email protected]) J I Published by Copernicus Publications on behalf of the European Geosciences Union. Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion 3877 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Abstract CPD The Sahel is the semi-arid transition zone between arid Sahara and humid tropical Africa, extending approximately 10–20◦ N from Mauritania in the West to Sudan in the 10, 3877–3900, 2014 East. The African continent, one of the most vulnerable regions to climate change, 5 is subject to frequent droughts and famine. One climate challenge research is to iso- Climatic information late those aspects of climate variability that are natural from those that are related of Western Sahel to human influences. -
NWS Unified Surface Analysis Manual
Unified Surface Analysis Manual Weather Prediction Center Ocean Prediction Center National Hurricane Center Honolulu Forecast Office November 21, 2013 Table of Contents Chapter 1: Surface Analysis – Its History at the Analysis Centers…………….3 Chapter 2: Datasets available for creation of the Unified Analysis………...…..5 Chapter 3: The Unified Surface Analysis and related features.……….……….19 Chapter 4: Creation/Merging of the Unified Surface Analysis………….……..24 Chapter 5: Bibliography………………………………………………….…….30 Appendix A: Unified Graphics Legend showing Ocean Center symbols.….…33 2 Chapter 1: Surface Analysis – Its History at the Analysis Centers 1. INTRODUCTION Since 1942, surface analyses produced by several different offices within the U.S. Weather Bureau (USWB) and the National Oceanic and Atmospheric Administration’s (NOAA’s) National Weather Service (NWS) were generally based on the Norwegian Cyclone Model (Bjerknes 1919) over land, and in recent decades, the Shapiro-Keyser Model over the mid-latitudes of the ocean. The graphic below shows a typical evolution according to both models of cyclone development. Conceptual models of cyclone evolution showing lower-tropospheric (e.g., 850-hPa) geopotential height and fronts (top), and lower-tropospheric potential temperature (bottom). (a) Norwegian cyclone model: (I) incipient frontal cyclone, (II) and (III) narrowing warm sector, (IV) occlusion; (b) Shapiro–Keyser cyclone model: (I) incipient frontal cyclone, (II) frontal fracture, (III) frontal T-bone and bent-back front, (IV) frontal T-bone and warm seclusion. Panel (b) is adapted from Shapiro and Keyser (1990) , their FIG. 10.27 ) to enhance the zonal elongation of the cyclone and fronts and to reflect the continued existence of the frontal T-bone in stage IV. -
Thermo-Convective Instability in a Rotating Ferromagnetic Fluid Layer
Open Phys. 2018; 16:868–888 Research Article Precious Sibanda* and Osman Adam Ibrahim Noreldin Thermo-convective instability in a rotating ferromagnetic fluid layer with temperature modulation https://doi.org/10.1515/phys-2018-0109 Received Dec 18, 2017; accepted Sep 27, 2018 1 Introduction Abstract: We study the thermoconvective instability in a Ferromagnetic fluids are colloids consisting of nanometer- rotating ferromagnetic fluid confined between two parallel sized magnetic particles suspended in a fluid carrier. The infinite plates with temperature modulation at the bound- magnetization of a ferromagnetic fluid depends on the aries. We use weakly nonlinear stability theory to ana- temperature, the magnetic field, and the density of the lyze the stationary convection in terms of critical Rayleigh fluid. The magnetic force and the thermal state of the fluid numbers. The influence of parameters such as the Taylor may give rise to convection currents. Studies on the flow number, the ratio of the magnetic force to the buoyancy of ferromagnetic fluids include, for example, Finalyson [1] force and the magnetization on the flow behaviour and who studied instabilities in a ferromagnetic fluid using structure are investigated. The heat transfer coefficient is free-free and rigid-rigid boundaries conditions. He used analyzed for both the in-phase and the out-of-phase mod- the linear stability theory to predict the critical Rayleigh ulations. A truncated Fourier series is used to obtain a number for the onset of instability when both a magnetic set of ordinary differential equations for the time evolu- and a buoyancy force are present. The generalization of tion of the amplitude of convection for the ferromagnetic Rayleigh Benard convection under various assumption is fluid flow. -
THE INFRARED CLOUD IMAGER by Brentha Thurairajah a Thesis Submitted in Partial Fulfi
THERMAL INFRARED IMAGING OF THE ATMOSPHERE: THE INFRARED CLOUD IMAGER by Brentha Thurairajah A thesis submitted in partial fulfillment of the requirements of the degree of Master of Science in Electrical Engineering MONTANA STATE UNIVERSITY Bozeman, Montana April 2004 © COPYRIGHT by Brentha Thurairajah 2004 All Rights Reserved ii APPROVAL of a thesis submitted by Brentha Thurairajah This thesis has been read by each member of the thesis committee and has been found to be satisfactory regarding content, English usage, format, citations, bibliographic style, and consistency, and is ready for submission to the college of graduate studies. Dr. Joseph A. Shaw, Chair of Committee Approved for the Department of Electrical and Computer Engineering Dr. James N. Peterson, Department Head Approved for the College of Graduate Studies Dr. Bruce R. McLeod, Graduate Dean iii STATEMENT OF PERMISSION TO USE In presenting this thesis in partial fulfillment of the requirements for a master’s degree at Montana State University, I agree that the Library shall make it available to borrowers under the rules of the Library. If I have indicated my intention to copyright this thesis by including a copyright notice page, copying is allowable only for scholarly purposes, consistent with “fair use” as prescribed in the U.S Copyright Law. Requests for permission for extended quotation from or reproduction of this thesis in whole or in parts may be granted only by the copyright holder. Brentha Thurairajah April 2nd, 2004 iv ACKNOWLEDGEMENT I would like to thank my advisor Dr. Joseph Shaw for always being there, for guiding me with patience throughout the project, for helping me with my course and research work through all these three years, and for providing helpful comments and constructive criticism that helped me complete this document. -
Thermal Equilibrium of the Atmosphere with a Convective Adjustment
jULY 1964 SYUKURO MANABE AND ROBERT F. STRICKLER 361 Thermal Equilibrium of the Atmosphere with a Convective Adjustment SYUKURO MANABE AND ROBERT F. STRICKLER General Circulation Research Laboratory, U.S. Weather Bureau, Washington, D. C. (Manuscript received 19 December 1963, in revised form 13 April 1964) ABSTRACT The states of thermal equilibrium (incorporating an adjustment of super-adiabatic stratification) as well as that of pure radiative equilibrium of the atmosphere are computed as the asymptotic steady state ap proached in an initial value problem. Recent measurements of absorptivities obtained for a wide range of pressure are used, and the scheme of computation is sufficiently general to include the effect of several layers of clouds. The atmosphere in thermal equilibrium has an isothermal lower stratosphere and an inversion in the upper stratosphere which are features observed in middle latitudes. The role of various gaseous absorbers (i.e., water vapor, carbon dioxide, and ozone), as well as the role of the clouds, is investigated by computing thermal equilibrium with and without one or two of these elements. The existence of ozone has very little effect on the equilibrium temperature of the earth's surface but a very important effect on the temperature throughout the stratosphere; the absorption of solar radiation by ozone in the upper and middle strato sphere, in addition to maintaining the warm temperature in that region, appears also to be necessary for the maintenance of the isothermal layer or slight inversion just above the tropopause. The thermal equilib rium state in the absence of solar insolation is computed by setting the temperature of the earth's surface at the observed polar value. -
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. -
A Meteorological and Blowing Snow Data Set (2000–2016) from a High-Elevation Alpine Site (Col Du Lac Blanc, France, 2720 M A.S.L.)
Earth Syst. Sci. Data, 11, 57–69, 2019 https://doi.org/10.5194/essd-11-57-2019 © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. A meteorological and blowing snow data set (2000–2016) from a high-elevation alpine site (Col du Lac Blanc, France, 2720 m a.s.l.) Gilbert Guyomarc’h1,5, Hervé Bellot2, Vincent Vionnet1,3, Florence Naaim-Bouvet2, Yannick Déliot1, Firmin Fontaine2, Philippe Puglièse1, Kouichi Nishimura4, Yves Durand1, and Mohamed Naaim2 1Univ. Grenoble Alpes, Université de Toulouse, Météo-France, CNRS, CNRM, Centre d’Etudes de la Neige, Grenoble, France 2Univ. Grenoble Alpes, IRSTEA, UR ETNA, 38042 St-Martin-d’Hères, France 3Centre for Hydrology, University of Saskatchewan, Saskatoon, SK, Canada 4Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan 5Météo France, DIRAG, Point à Pitre, Guadeloupe, France Correspondence: Florence Naaim-Bouvet (fl[email protected]) Received: 12 June 2018 – Discussion started: 25 June 2018 Revised: 8 October 2018 – Accepted: 9 November 2018 – Published: 11 January 2019 Abstract. A meteorological and blowing snow data set from the high-elevation experimental site of Col du Lac Blanc (2720 m a.s.l., Grandes Rousses mountain range, French Alps) is presented and detailed in this pa- per. Emphasis is placed on data relevant to the observations and modelling of wind-induced snow transport in alpine terrain. This process strongly influences the spatial distribution of snow cover in mountainous terrain with consequences for snowpack, hydrological and avalanche hazard forecasting. In situ data consist of wind (speed and direction), snow depth and air temperature measurements (recorded at four automatic weather stations), a database of blowing snow occurrence and measurements of blowing snow fluxes obtained from a vertical pro- file of snow particle counters (2010–2016). -
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.