DOCSLIB.ORG

Clouds First Midterm Exam Is Next Friday!

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Clouds First Midterm Exam Is Next Friday! Clouds First midterm exam is next Friday! The exam will be in-class, during our regular lecture • on Friday September 28 at 9:35 am. The exam will be CLOSED BOOK • ♦ No textbooks ♦ No calculators ♦ No cheat-sheets • Alternate seating • The grades will be posted on WebCT • The exam covers Chapters 1,2,3,4,5, and 19. • Office hours: next Wednesday 10:30-11:30 am. RECAP Dew - condensation on cold surfaces. • Frost - deposition on very cold surfaces. • Haze - condensation on small airborne particles. • Fog – saturated wet haze, visibility <1 km. • ♦ Radiation fog – driven by radiation cooling ♦ Advection fog – driven by air movement ♦ Upslope fog - topography driven ♦ Evaporation fog – cold air above warm body of water. Clouds Definition: visible aggregate of tiny water droplets or • ice crystals suspended in air Classification: four major cloud groups according to the • height (of the cloud base). Within each group there are different types identified by their appearance ♦ High (cirrus: Latin for “wisp of hair”) •Cirrus, Cirrostratus, Cirrocumulus ♦ Middle (alto, from the Latin altus: “high”) •Altostratus, Altocumulus ♦ Low (stratus, Latin for “layer”) •Stratus, Stratocumulus, Nimbostratus ♦ Clouds with vertical extension (cumulus: ”heap”) •Cumulus, Cumulonimbus Basic Cloud Types What are the important things to know Composition: recall that in the troposphere the • temperature drops with altitude. ♦ High clouds (16,000 – 43,000 ft in midlatitudes) are made mostly of ice ♦ Middle clouds (6,500 – 23,000 ft in midlatitudes) are composed of water droplets and some ice crystals (higher up or when the temperature is low) ♦ Low clouds (surface to 6,500 ft in midlatitudes) are composed primarily of water droplets except in very cold weather when it snows For reference: commercial aircraft flies around • 30,000 ft. High Clouds • Form at high altitudes (above 16,000-20,000 ft). • Composed mostly from ice crystals. • Appear white and very thin. Cirrus clouds (this transparency’s background): • ♦ thin wispy clouds ♦ blown by strong high altitude winds (jetstream) ♦ typically move from west to east (?) ♦ point to fair, pleasant weather ???cumulus types Small, rounded puffy, in • parallel waves or bands Cirrocumulus (high) • ♦ “mackerel sky” • Altocumulus (middle) • Stratocumulus (low) ???stratus types Cirrostratus (high) • ♦ Halo around sun/moon Altostratus (middle) • ♦ Sun dimly visible Stratus (low) • ♦ No sun, like thick fog Cumulonimbus cloud Thunderstorm cloud with a very dark base. • Large vertical extent (several km thick). • The top may be flattened by winds (anvil). • It can occur as a single isolated cloud or a wall of • clouds. All types of precipitation are possible: strong • showers, snow, hail. Lightning is very likely. Tornadoes are possible. They are associated with large amount of energy • release, strong up- and down-drafts. Other types of clouds Clouds driven by topography: • some sort of a barrier present: ♦ Cap clouds: wind over a mountain or ♦ Lenticular clouds: formed over a mountain ♦ Banner cloud: downwind of an isolated mountain top. Mammatus clouds: typically under cumulus clouds. • Condensation trails from jet aircrafts: adding water vapor, • providing condensation nuclei, cooling of the air flowing over the wing. Very high altitude clouds: • ♦ noctilucent clouds: 75-90 km above the surface; ♦ Where is the water coming from? - meteorites, CH4 chemistry. Cap cloud Lenticular clouds The clouds form on the lee side of the mountains in the crests of the mountain wave. Can be confused with UFOs Banner cloud Observing the Earth from Space Geostationary satellites: • ♦ Orbit the equator at the same rate as the Earth spins at about 36000 km above the surface. ♦ Remain above a fixed spot on the Earth surface. ♦ Provide continuous monitoring of a specific region Polar-orbiting satellites. • ♦ Provide global coverage of the planet, move slightly westward on each pass ♦ Have a lower orbit (~850 km). ♦ Observe the area straight beneath them. Satellite observations Visible wavelengths: • ♦ Use the reflected sun light from the top of the clouds. ♦ The albedo of the clouds gives information about the thickness of the cloud. ♦ No temperature information about the clouds. Infrared observations: • ♦ IR light emitted from the clouds. ♦ Provide T information about the clouds. ♦ This can be converted into altitude information. ♦ Using different wavelengths in the IR one can obtain 3D information about the structure of the clouds. Name that cloud! Cirrocumulus Altostratus Altocumulus Cirrostratus.
Load more

Recommended publications
  • 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.
    [Show full text]
  • Guidance on the Harmonized WAFS Grids for Cumulonimbus Cloud, Icing and Turbulence Forecasts
    Guidance on the Harmonized WAFS Grids for Cumulonimbus Cloud, Icing and Turbulence Forecasts. Version 2.5 13 September 2012 Guidance on the Harmonized WAFS Grids for Cumulonimbus Cloud, Icing and Turbulence forecasts. Contents 1. Introduction ....................................................................................................................... 2 2. General Description of Data ............................................................................................. 2 3. Description of Data Values ............................................................................................... 4 4. Grid Interpolation ............................................................................................................. 5 5. Description of the Harmonization Process ..................................................................... 5 6. Explanation of differences between the WAFS gridded forecasts for CB cloud, icing and turbulence and the WAFS significant weather (SIGWX) forecasts ............................. 6 7. Suggested usage of WAFS gridded forecasts for Cb cloud, icing and turbulence ...... 8 7.1 General principles ..................................................................................................... 8 7.2 Use of the WAFS Clear Air Turbulence (CAT) gridded forecast ........................ 8 7.3 Use of the WAFS icing gridded forecast ................................................................. 9 7.4 Use of the WAFS Cb cloud gridded forecasts .....................................................
    [Show full text]
  • Lightning Dr
    ESCI 340 - Cloud Physics and Precipitation Processes Lesson 12 - Lightning Dr. DeCaria References: The Lightning Discharge, Uman The Electrical Nature of Storms, MacGorman and Rust Fundamentals of Lightning, Rakov `Runaway Breakdown and the Mysteries of Lightning', Gurevich and Zybin, Physics Today, 2005 Mechanisms of Charge Separation • The top of a thunderstorm (cumulonimbus) cloud becomes positively charged, while the middle-to-lower portions of the cloud becomes negatively charged. • Often there is also a smaller pocket of positive charge near the bottom of the cloud. • The reason for this charge separation is not completely understood, but some of the more prominent theories are described below. • Those mechanisms requiring a preexisting electric field are called inductive charging mechanisms, while those not requiring a preexisting electric field are called nonin- ductive charging mechanisms. Inductive ion capture: In a preexisting electrical field, there will be a separation of charge across a hydrometeor. As the hydrometeor falls, gaseous ions will either be attracted or repelled from the underside of the hydrometeor, depending on their sign. Thus, the hydrometeor will gain an increasing charge of whatever sign it has on its topside. In Fig. 1 the positive ions are repelled as the hydrometeor falls, but the negative ions are attracted. Thus, the hydrometeor gains a net negative charge as it falls. Figure 1: Inductive ion capture. 1 Ion capture may play a role in weakly electrified storms, but cannot be used to explain the amount of charge separation seen in a thunderstorm without the presence of other mechanisms. Inductive particle rebound: Two hydrometeors in a preexisting electric field, falling at different speeds, will exchange charge during collision as shown in Fig.
    [Show full text]
  • 20 WCM Words
    Spring, 2017 - VOL. 22, NO. 2 Evan L. Heller, Editor/Publisher Steve DiRienzo, WCM/Contributor Ingrid Amberger, Webmistress FEATURES 2 Ten Neat Clouds By Evan L. Heller 10 Become a Weather-Ready Nation Ambassador! By Christina Speciale 12 Interested in CoCoRaHS? By Jennifer Vogt Miller DEPARTMENTS 14 Spring 2017 Spotter Training Sessions 16 ALBANY SEASONAL CLIMATE SUMMARY 18 Tom Wasula’s WEATHER WORD FIND 19 From the Editor’s Desk 20 WCM Words Northeastern StormBuster is a semiannual publication of the National Weather Service Forecast Office in Albany, New York, serving the weather spotter, emergency manager, cooperative observer, ham radio, scientific and academic communities, and weather enthusiasts, all of whom share a special interest or expertise in the fields of meteorology, hydrology and/or climatology. Non-Federal entities wishing to reproduce content contained herein must credit the National Weather Service Forecast Office at Albany and any applicable authorship as the source. 1 TEN NEAT CLOUDS Evan L. Heller Meteorologist, NWS Albany There exist a number of cloud types based on genera as classified in the International Cloud Atlas. Each of these can also be sub-classified into one of several possible species. These can further be broken down into one of several varieties, which, in turn, can be further classified with supplementary features. This results in hundreds of different possibilities for cloud types, which can be quite a thrill for cloud enthusiasts. We will take a look at 10 of the rarer and more interesting clouds you may or may not have come across. A. CLOUDS INDICATING TURBULENCE 1. Altocumulus castellanus – These are a species of mid-level clouds occurring from about 6,500 to 16,500 feet in altitude.
    [Show full text]
  • Structure and Evolution of a Cumulonimbus Cloud Developed Over a Mountain Slope with the Arrival of Sea Breeze in Summer
    Journal of the Meteorological Society of Japan, Vol. 84, No. 4, pp. 613--640, 2006 613 Structure and Evolution of a Cumulonimbus Cloud Developed over a Mountain Slope with the Arrival of Sea Breeze in Summer Tetsuya SANO and Kazuhisa TSUBOKI Hydrospheric Atmospheric Research Center, Nagoya University, Nagoya, Japan (Manuscript received 10 June 2005, in final form 4 April 2006) Abstract Cumulonimbus clouds frequently develop over mountains, a plain, and the sea in the summer in as- sociation with thermally induced local circulations. On July 5, 2000, when the sea breeze from the Pacific Ocean blew over the Noubi Plain and arrived at the slope of the Ibuki Mountains where a valley wind circulation developed, a cumulonimbus cloud occurred over the slope of the Ibuki Mountains. In this pa- per, the structure and evolution of the cumulonimbus cloud are investigated using the data of Doppler radars. The direction of the environmental vertical wind shear was southeast, which is parallel to the slope of the Ibuki Mountains, when the cumulonimbus cloud occurred. The cumulonimbus cloud maintained for about 2 hours. The cumulonimbus cloud consisted of groups of precipitating cells; ‘‘Primary Cell’’ and ‘‘Secondary Cells.’’ The former developed with tilting toward the downshear side and moved down the slope. The latter developed almost uprightly on the upshear side of the Primary cell. There were 6 groups of cells in the cumulonimbus cloud. The developing process and structure of group C, which was the most intense group, were investi- gated in detail. After Primary Cell C1, with tilting toward the downshear side, developed, Secondary Cells C2, C3 and C4 of group C developed on the upshear side (the Ibuki Mountains side) of cell C1.
    [Show full text]
  • Stratiform Precipitation in Regions of Convection: a Meteorological Paradox?
    Stratiform Precipitation in Regions of Convection: A Meteorological Paradox? Robert A. Houze Jr. University of Washington, Seattle, Washington ABSTRACT It was once generally thought that stratiform precipitation was something occurring primarily, if not exclusively, in middle latitudes—in baroclinic cyclones and fronts. Early radar observations in the Tropics, however, showed large ra- dar echoes composed of convective rain alongside stratiform precipitation, with the stratiform echoes covering great areas and accounting for a large portion of the tropical rainfall. These observations seemed paradoxical, since stratiform precipitation should not have been occurring in the Tropics, where baroclinic cyclones do not occur. Instead it was fall- ing from convection-generated clouds, generally thought to be too violent to be compatible with the layered, gently set- tling behavior of stratiform precipitation. In meteorology, convection is a dynamic concept; specifically, it is the rapid, efficient, vigorous overturning of the atmosphere required to neutralize an unstable vertical distribution of moist static energy. Most clouds in the Tropics are convection-generated cumulonimbus. These cumulonimbus clouds contain an evolving pattern of newer and older pre- cipitation. The young portions of the cumulonimbus are too violent to produce stratiform precipitation. In young, vigor- ous convective regions of the cumulonimbus, precipitation particles increase their mass by collection of cloud water, and the particles fall out in heavy showers, which appear on radar as vertically oriented convective “cells.” In regions of older convection, however, the vertical air motions are generally weaker, and the precipitation particles drift downward, with the particles increasing their mass by vapor diffusion. In these regions the radar echoes are stratiform, and typically these echoes occur adjacent to regions of younger convective showers.
    [Show full text]
  • The Status and Possible Evolution of Climate
    BACKGROUND REPORT ON THE STATUS AND POSSIBLE EVOLUTION OF CLIMATE PROJECTIONS IN WEST AFRICA OCTOBER 2013 This report is made possible by the support of the American people through the U.S. Agency for International Development OCTOBER 2013 (USAID). The contents are the sole responsibility of Tetra Tech ARD and do not necessarily reflect the views of USAID or the U.S. Government. This report is made possible by the support of the American people through the U.S. Agency for International Development (USAID). The contents are the sole responsibility of Tech ARD and do not necessarily reflect the views of USAID or the U.S. Government. Contributors to this report, in alphabetical order: Ross Blamey,1 Lisa Coop,1 Christopher Jack,1 Ben Loveday,2 and Kate Sutherland.1 1 Climate Systems Analysis Group (CSAG), University of Cape Town 2 Department of Oceanography, University of Cape Town Cover Photo: Sunrise in Dakar, David Miller, 2013 This publication was produced for the United States Agency for International Development by Tetra Tech ARD, through a Task Order under the Prosperity, Livelihoods, and Conserving Ecosystems (PLACE) Indefinite Quantity Contract Core Task Order (USAID Contract No. AID-EPP-I-00-06-00008, Order Number AID-OAA-TO-11-00064). Tetra Tech ARD Contacts: Patricia Caffrey Chief of Party African and Latin American Resilience to Climate Change (ARCC) Burlington, Vermont Tel.: 802.658.3890 [email protected] Anna Farmer Project Manager Burlington, Vermont Tel.: 802-658-3890 [email protected] BACKGROUND PAPER ON THE STATUS AND POSSIBLE EVOLUTION OF CLIMATE PROJECTIONS IN WEST AFRICA AFRICAN AND LATIN AMERICAN RESILIENCE TO CLIMATE CHANGE (ARCC) OCTOBER 2013 The Status and Possible Evolution of Climate Projections in West Africa i TABLE OF CONTENTS ACRONYMS AND ABBREVIATIONS .......................................................................................
    [Show full text]
  • The Ten Different Types of Clouds
    THE COMPLETE GUIDE TO THE TEN DIFFERENT TYPES OF CLOUDS AND HOW TO IDENTIFY THEM Dedicated to those who are passionately curious, keep their heads in the clouds, and keep their eyes on the skies. And to Luke Howard, the father of cloud classification. 4 Infographic 5 Introduction 12 Cirrus 18 Cirrocumulus 25 Cirrostratus 31 Altocumulus 38 Altostratus 45 Nimbostratus TABLE OF CONTENTS TABLE 51 Cumulonimbus 57 Cumulus 64 Stratus 71 Stratocumulus 79 Our Mission 80 Extras Cloud Types: An Infographic 4 An Introduction to the 10 Different An Introduction to the 10 Different Types of Clouds Types of Clouds ⛅ Clouds are the equivalent of an ever-evolving painting in the sky. They have the ability to make for magnificent sunrises and spectacular sunsets. We’re surrounded by clouds almost every day of our lives. Let’s take the time and learn a little bit more about them! The following information is presented to you as a comprehensive guide to the ten different types of clouds and how to idenify them. Let’s just say it’s an instruction manual to the sky. Here you’ll learn about the ten different cloud types: their characteristics, how they differentiate from the other cloud types, and much more. So three cheers to you for starting on your cloud identification journey. Happy cloudspotting, friends! The Three High Level Clouds Cirrus (Ci) Cirrocumulus (Cc) Cirrostratus (Cs) High, wispy streaks High-altitude cloudlets Pale, veil-like layer High-altitude, thin, and wispy cloud High-altitude, thin, and wispy cloud streaks made of ice crystals streaks
    [Show full text]
  • New Possible Mechanisms of Thunderstorm Clouds Physics Manana Kachakhidze, Nino Kachakhidze-Murphy Georgian Technical University
    New Possible Mechanisms of Thunderstorm Clouds Physics Manana Kachakhidze, Nino Kachakhidze-Murphy Georgian Technical University, Faculty of Informatics and Management Systems Correspondence to: [email protected] Abstract The work provides possible mechanisms of physics of thunderstorm clouds. We tried to consider the problems of the hail clouds in a completely different view. The article is based on the latest scientific achievement of modern theoretical physics, chemistry, physics of thunderstorms clouds and gives opportunities for new ways searching of impact on hail clouds. Introduction It is known that a strong earthquake preparation process can be accompanied by various geophysical anomalies, which expose themselves several months, weeks or days prior to earthquakes. Such as: Changing of intensity of electro-telluric current in focal area; Perturbations of geomagnetic field in forms of irregular pulsations or regular short-period pulsations; Perturbations of atmospheric electric field; Irregular changing of characteristic parameters of the lower ionosphere (plasma frequency, electron concentration, height of D layer, etc.); Irregular perturbations reaching the upper ionosphere, namely F2-layer, for 2-3 days before the earthquake; Increased intensity of electromagnetic emissions in upper ionosphere in several hours or tenths of minutes before earthquake; Lighting before earthquake; Infrared radiation; Total Electron Content (TEC) anomalies; Changing of weather parameters. Physical mechanisms of the mentioned phenomena by us are explained on the base of the classical electrodynamics [16]. As it was expected, in the origination of the above mentioned anomalies the defining role electromagnetic radiation plays. Exceptions are not the case of cloudiness intensification, which, of course, implies a good weather change with the "bad weather".
    [Show full text]
  • SD Front Cover Color
    FEBRUARY 1999 VOLUME 41 NUMBER 2 STORMSTORM DATADATA AND UNUSUAL WEATHER PHENOMENA WITH LATE REPORTS AND CORRECTIONS NATIONAL OCEANIC AND NATIONAL ENVIRONMENTAL SATELLITE NATIONAL CLIMATIC DATA CENTER noaa ATMOSPHERIC ADMINISTRATION DATA, AND INFORMATION SERVICE ASHEVILLE, N.C. Cover: A Cumulonimbus cloud just southeast of Asheville, NC. This storm produced heavy rainfall amounts and strong straight-line winds in the Fairview area. (Photograph courtesy of Stuart Hinson, Meteorologist, NCDC, Asheville, NC) TABLE OF CONTENTS Page Outstanding Storms of the Month ……………………………………………………………………………………….. 6 Storm Data and Unusual Weather Phenomena ………………………………………………………………………….. 7 Additions/ Corrections …………………………………………………………………………………………………… 127 Reference Notes …………………………………………………………………………………………………………. 137 STORM DATA (ISSN 0039-1972) National Climatic Data Center Editor: Stephen Del Greco Assistant Editor: Stuart Hinson Publication Staff: Noel Risnychok STORM DATA is prepared, funded, and distributed by the National Oceanic and Atmospheric Administration (NOAA). The Outstanding Storms of the Month section is prepared by the Data Operations Branch of the National Climatic Data Center. The Storm Data and Unusual Weather Phenomena narratives and Hurricane/Tropical Storm summaries are prepared by the National Weather Service. Monthly and annual statistics and summaries of tornado and lightning events resulting in deaths, injuries, and damage are compiled by cooperative efforts between the National Climatic Data Center and the Storm Prediction Center. STORM DATA contains all confirmed information on storms available to our staff at the time of publication. However, due to difficulties inherent in the collection of this type of data, it is not all-inclusive. Late reports and corrections are printed in each edition. Maps of the National Weather Service County Warning Areas which are used in the Storm Data and Unusual Weather Phenomena section will be printed in all editions.
    [Show full text]
  • Considerations Regarding Management Optimization
    “Mircea cel Batran” Naval Academy Scientific Bulletin, Volume XVI – 2013 – Issue 2 Published by “Mircea cel Batran” Naval Academy Press, Constanta, Romania METEOROLOGY TERMS AND THEIR SURPRISING MEANINGS AND ORIGINS Simona-Cătălina COSMA Abstract: All scientific fields have specialized words, many of them very arcane to outsiders. Meteorology, as interdisciplinary scientific study of the atmosphere and its phenomena, has its fare share of specialized words. They form a scientific jargon used to refer to different kinds of atmospheric phenomena and to different instruments used to measure their intensity. Many of these terms, referring to various kinds of winds and windstorms, to types of clouds and forms of precipitation, for example, are words that have a long and intricate history which, in many cases, is closely related to certain parts of the world and their specific climates. This paper attempts to put together various examples of “weather words” that have quite surprising meanings and origins and thus give a helping hand to those who are interested in delving into the study of atmospheric phenomena, of weather and climate, and ultimately of our environment. Key words: weather, meteorology, wind, cloud, precipitation 1. INTRODUCTION Tempest traces back its origin to the Vulgar Let us begin by drawing a distinction between Latin word tempest meaning season, weather, storm, a two words that are commonly, yet erroneously, used as word stemming from the word tempus meaning time. synonyms: weather and climate. Weather refers to the In contrast with a tornado, which is a twisted wind, a condition or state of the atmosphere at a particular place derecho is defined as a widespread, long-lived, straight- over a short period of time, while climate refers to the line windstorm associated with a fast-moving band of weather pattern of a place over a long period of time, long severe thunderstorms.
    [Show full text]
  • Chapter 13, Section 1: Thunderstorms
    Earth Science Identify the processes that form thunderstorms Compare and contrast different types of thunderstorms Describe the life cycle of a thunderstorm At any given moment, nearly 2000 thunderstorms are in progress around the world Both geography and air mass movements make thunderstorms most common in the southeastern United States For a thunderstorm to form, three conditions must exist A source of moisture For a thunderstorm to form, there must be an abundant source of moisture in the lower levels of the atmosphere Lifting of the air mass For a thunderstorm to form, there must be some mechanism for moisture to condense and release its latent heat This occurs when a warm air mass is lifted into a cooler region of the atmosphere An unstable atmosphere If the surrounding air remains cooler than the rising air mass, the unstable conditions can produce clouds that grow upward This releases more latent heat and allows continued lifting Because the rate of condensation diminishes with height, most cumulonimbus clouds are limited to about 12,000 m Thunderstorms are also limited by duration and size Thunderstorms are often classified according to the mechanism that causes the air mass that formed them to rise There are two main types of thunderstorms Air-mass Frontal When air rises because of unequal heating of Earth’s surface beneath one air mass, the thunderstorm is called an air-mass thunderstorm There are two kinds of air-mass thunderstorms Mountain thunderstorms Occurs when an air mass rises by orographic lifting
    [Show full text]