DOCSLIB.ORG

Forecaster's Guide to Tropical Meteorology

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Forecaster's Guide to Tropical Meteorology Air Weather Service Technical Report 240 Forecaster’s Guide to Tropical Meteorology Second Edition, 1991 by Maj. Gary D. Atkinson, USAF revised by C.S. Ramage * DOES NOT CONTAIN GRAPHICS * 1 April 1971 / Revised August 1991 (Second Draft) PDF version published by Weather Graphics weathergraphics.com No copyright claimed No restriction on distribution PREFACE TO SECOND EDITION As correctly forecast in the Preface to the first edition, Forecasters’ Guide to Tropical Meteorol- ogy was used not only to train Air Weather Service meteorologists, but also as a text for university courses. It was even translated into Chinese. Technological advances in the last twenty years, especially in satellite-based observations, have not seriously affected views expressed in the first edition, but have allowed them to be expanded and refined. Both climatology and synoptic meteorology have benefited, while many hitherto obscure parts of the tropics have been exposed to the global eye. In this edition, satellite data and wide-ranging research have allowed the tropics to be treated more evenly and extensively than before. Sections dealing with Africa, the Americas and south and southwest Asia have been expanded. Satellite pictures illustrate tropical systems and processes. Besides these changes, the following topics have been either added to (bold face) or re- moved from (italics) the first edition. Chapter 1. Terminology; heat lows. Chapter 2. Stress-differential along a coast. Chapter 3. Constant-level balloons; surface reports from buoys; Doppler radar; Profiler. Chapter 4. Low-level jet streams. Chapter 5. Upwelling; tradewinds; low-latitude westerlies. Chapter 6. Fog; character of significant rain in the tropics; interannual variation of rainfall and El Niño; seasonal distribution of rainfall and the monsoons; pentad distribution of rainfall. Chapter 7. A new chapter on diurnal variation, combining the scattered discussions of the first edition, and expanding and adding to them. New sections on vertical mixing, stratocu- mulus and fog, and squall lines. Chapter 8 (formerly Chapter 7). Equatorial waves; monsoon depressions; squall lines; surges; troughs in the upper-tropospheric westerlies; South Pacific convergence zone; superposition of tropical and extra-tropical disturbances; near-equatorial convergence zones Chapter 10 (formerly Chapter 9). Duststorms. Chapter 11 (formerly Chapter 10). Isogon analysis; kinematic frontal analysis. Chapter 12 (formerly Chapter 11). Stability indexes (reduced); preparing to forecast in a new area; 30-60 day cycles; Atlantic tropical storms (seasonal forecasts); preparing to fore- cast in a new area. FIGURES: 137 have been retained and 171 added. REFERENCES: 177 have been retained and 367 added. The range of topics and locations cannot be simply dealt with sequentially; to avoid repeti- tion, extensive cross-referencing has been used. Detailed subject, geographical and author indexes have been added, as well as a fold-out locator map. ACKNOWLEDGMENTS. Many present and former members of Air Weather Service con- tributed to the preparation of this edition, including the sixteen who carefully and con- structively reviewed the first and second drafts, and those who provided weather satellite pictures, bibliographies and publications. I particularly appreciated Garry Atkinson’s comments. Louis Oda drafted and revised the figures, Thomas Schroeder, was responsible for administration. Others who helped included Mike Gentry, William Gray, Barry Hinton, Richard Orville, Patrick Sham, Norman Wagner, J.F. White, Scott Woodruff, and X. Ziang. My wife Alice proofread. C.S. Ramage 1991 TABLE OF CONTENTS CHAPTER 1 - INTRODUCTION CHAPTER 2 - PRIMARY PHYSICAL CONTROLS OF THE TROPICAL CIRCULATION CHAPTER 3 - THE OBSERVATIONAL BASIS CHAPTER 4 - PRESSURE AND WINDS CHAPTER 5 - TEMPERATURE AND WATER VAPOR CHAPTER 6 - CLOUDINESS AND RAINFALL CHAPTER 7 - DIURNAL VARIATIONS CHAPTER 8 - TROPICAL SYNOPTIC MODELS CHAPTER 9 - TROPICAL CYCLONES CHAPTER 10 - SEVERE WEATHER IN THE TROPICS CHAPTER 11 - TROPICAL ANALYSIS CHAPTER 12 - TROPICAL FORECASTING Chapter 1 INTRODUCTION A. General each year, but since 1950 more than 5000 operational and research reconnaissance flights have been made into cyclone centers. The urge to understand tropical meteorol- By contrast, one Arabian Sea mid-tropo- ogy has been driven by a variety of forces: spheric cyclone, one monsoon depression, the devastation caused by tropical cyclones; and two upper-tropospheric cold lows have demands by military operations, e.g. World been reconnoitered. Fifteen single-aircraft War II, the Marshall Islands weapons tests, research traverses have been made across and the conflict in southeast Asia; and the the near-equatorial convergence zone, but belief of influential mid-latitude meteorolo- none into the mysterious weak circulations gists that the tropics may hold the key to that can cause disastrous floods. For most successful forecasts of global weather pat- generating regions, about one hundred terns and climate change. Efforts by World years of daily tropical cyclone positions Weather Watch (WWW) and the Global provide the basis of detailed, authoritative Atmospheric Research Program (GARP), climatologies. Apart from monsoon depres- including the GARP Atlantic Tropical Ex- sions, not even a year of tracks has been periment (GATE) of 1974 and the Winter plotted for other tropical vortexes. and Summer Monsoon Experiments (WMONEX and SMONEX) of December This disproportion, though slightly reduced 1978 and June-July 1979, gave many meteo- by squall-line studies in GATE, Venezuela rologists their first experience of the tropics. and the Amazon, and a 1987 field study of Research papers proliferated, concentrating early-summer rain systems off southeast on the small time and space scales described China (Taiwan Area Mesoscale Experiment by the special observing systems (aerial —TAMEX), means that the meteorologist reconnaissance, rawinsondes, and radars) trying to forecast tropical cyclones is served set up for the experiments. by a variety of subjective, numerical and statistical techniques, by special services But where does all this leave the field fore- from global prediction centers, and by 15- caster? A case study dependent on data not minute satellite updates. For the other 99.9 operationally available, and supported by percent of the time, forecasters are pretty brief, doubtful statistics, doesn’t help much much on their own. This manual tries to in the day-to-day grind of tropical analysis redress the balance. It devotes one chapter and forecasting. to tropical cyclones, while emphasizing Predicting tropical cyclones taps almost all other weather systems, background the resources available to aid the tropical climatologies, and forecasting hints and forecaster. Riehl (1979) devotes a chapter to pitfalls. numerical hurricane prediction and nothing Observational information on the tropics to other tropical forecasting. On an average increased significantly through the 1970s, day in the tropics less than one tenth of one though progress has been patchy over percent of the area is affected by a tropical Africa and the Americas. Weather radars cyclone. Only about 80 cyclones develop operate at many tropical stations, and there is great potential for more aircraft weather of tropical meteorology in much greater reports. Compared to twenty years ago, detail than is possible here. human observations are now fewer; auto- The forecaster is viewed as an applied mated observations, especially those from researcher who can evaluate hypotheses and satellites, are vastly more, and are not yet come up with new ideas. He should realize fully exploited. that in the tropics weather mechanisms are There is an urgent need to synthesize from often not understood. “Authoritative” opin- these diverse observational systems a ions may differ, for example, on the preva- coherent basis for the analysis and predic- lence of easterly waves, on the cause of the tion of tropical circulations and associated quasi-biennial oscillation, on predicting El weather. Our ability to digest and use this Niño, and on generation, movement and information in tropical numerical models dissipation of surges. Even when there is has not kept pace with numerical weather general agreement, such as on tropical prediction in middle latitudes. This is par- cyclone dissipation, diurnal variations along tially due to the greater complexity of a mountainous coast, and the role of surface weather systems and interactions between cooling in causing fog, apparent exceptions various scales of motion in the tropics. Thus, may occur. Chapters 2 through 6, besides although world-wide predictions are being including a chapter (3) on data, focus on the made, at least in the near future, tropical annual cycle and monthly averages, while weather forecasting will continue to depend making some attempt to interpret them in heavily on subjective judgment aided by terms of weather. Chapter 7 covers diurnal selected numerical products such as objec- effects. The remaining chapters concern tive wind analyses, global long-wave predic- weather analysis and forecasting. Here tions and computer-processed satellite data. astronomical control by the annual and diurnal cycles is muted by complex feed- West Pacific typhoons and Atlantic hurri- backs among atmosphere, ocean, and ter- canes are the same phenomenon — they rain. need not be separately described. Thunder- storms also possess the same characteristics world-wide. What is not so well-known
Load more

Recommended publications
  • 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.
    [Show full text]
  • L'île De La Réunion Sous L'œil Du Cyclone Au Xxème Siècle. Histoire
    L’île de La Réunion sous l’œil du cyclone au XXème siècle. Histoire, société et catastrophe naturelle Isabelle Mayer Jouanjean To cite this version: Isabelle Mayer Jouanjean. L’île de La Réunion sous l’œil du cyclone au XXème siècle. Histoire, société et catastrophe naturelle. Histoire. Université de la Réunion, 2011. Français. NNT : 2011LARE0030. tel-01187527v2 HAL Id: tel-01187527 https://tel.archives-ouvertes.fr/tel-01187527v2 Submitted on 27 Aug 2015 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UNIVERSITE DE LA REUNION FACULTE DES LETTRES ET SCIENCES HUMAINES L’île de La Réunion sous l’œil du cyclone au XXème siècle. Histoire, société et catastrophe naturelle. TOME I Thèse de doctorat en Histoire contemporaine présentée par Isabelle MAYER JOUANJEAN Sous la direction du Professeur Yvan COMBEAU Le jury : -Pascal Acot, C.R.H. C.N.R.S., H.D.R., Université de Paris I – Panthéon Sorbonne ; C.N.R.S. -Yvan Combeau, Professeur d’Histoire contemporaine, Université de La Réunion -René Favier, Professeur d’Histoire moderne, Université Pierre Mendès France – Grenoble II -Claude Prudhomme, Professeur d’Histoire contemporaine, Université Lumière - Lyon II -Claude Wanquet, Professeur d’Histoire moderne émérite, Université de La Réunion Soutenance - 23 novembre 2011 « Les effets destructeurs de ces perturbations de saison chaude, dont la fréquence maximale est constatée en février, sont bien connus, tant sur l’habitat que sur les équipements collectifs ou les cultures.
    [Show full text]
  • Preparatory Survey Report on the Mauritius Meteorological Services Project in the Republic of Mauritius
    Mauritius Meteorological Services The Republic of Mauritius PREPARATORY SURVEY REPORT ON THE MAURITIUS METEOROLOGICAL SERVICES PROJECT IN THE REPUBLIC OF MAURITIUS November 2012 JAPAN INTERNATIONAL COOPERATION AGENCY JAPAN WEATHER ASSOCIATION INTERNATIONAL METEOROLOGICAL CONSULTANT INC. GE JR 12-143 Summary Summary Mauritius, a country consisting of small islands, is located in the cyclone-prone area of the Southwest Indian Ocean and is often affected by natural disasters such as heavy storms, tidal waves and floods caused by tropical cyclones, landslides and so on. Recently, climate change caused by global warming has posed a serious problem for Mauritius as it is predicted to have significant negative impacts on small island nations which are particularly vulnerable to a change in the natural environment. In addition, it is said that climate change has a potential to become the greatest threat to the sustainability of the very foundations of human survival. Thus, it is a significant global issue which developed and developing countries alike must deal with in mutually beneficial cooperation. In line with increasing global concerns on the intensification of disasters caused by climate change, the establishment of effective countermeasures against disasters such as severe storms, storm surges, and floods caused by tropical cyclones, rising sea level, tsunami, etc. has been an urgent task in Mauritius as well as in other countries in the Southwest Indian Ocean. In order for Mauritius to contribute to the alleviation of natural disasters in the Southwest Indian Ocean, the following are required and strongly desired: 1) An efficient meteorological observation system; and, 2) An Exchange of meteorological observation data and information about cyclones with neighboring countries in the Southwest Indian Ocean on a timely basis.
    [Show full text]
  • Rapid Intensification of a Sheared Tropical Storm
    OCTOBER 2010 M O L I N A R I A N D V O L L A R O 3869 Rapid Intensification of a Sheared Tropical Storm JOHN MOLINARI AND DAVID VOLLARO Department of Atmospheric and Environmental Sciences, University at Albany, State University of New York, Albany, New York (Manuscript received 10 February 2010, in final form 28 April 2010) ABSTRACT A weak tropical storm (Gabrielle in 2001) experienced a 22-hPa pressure fall in less than 3 h in the presence of 13 m s21 ambient vertical wind shear. A convective cell developed downshear left of the center and moved cyclonically and inward to the 17-km radius during the period of rapid intensification. This cell had one of the most intense 85-GHz scattering signatures ever observed by the Tropical Rainfall Measuring Mission (TRMM). The cell developed at the downwind end of a band in the storm core. Maximum vorticity in the cell exceeded 2.5 3 1022 s21. The cell structure broadly resembled that of a vortical hot tower rather than a supercell. At the time of minimum central pressure, the storm consisted of a strong vortex adjacent to the cell with a radius of maximum winds of about 10 km that exhibited almost no tilt in the vertical. This was surrounded by a broader vortex that tilted approximately left of the ambient shear vector, in a similar direction as the broad precipitation shield. This structure is consistent with the recent results of Riemer et al. The rapid deepening of the storm is attributed to the cell growth within a region of high efficiency of latent heating following the theories of Nolan and Vigh and Schubert.
    [Show full text]
  • 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.
    [Show full text]
  • Tornado Safety Q & A
    TORNADO SAFETY Q & A The Prosper Fire Department Office of Emergency Management’s highest priority is ensuring the safety of all Prosper residents during a state of emergency. A tornado is one of the most violent storms that can rip through an area, striking quickly with little to no warning at all. Because the aftermath of a tornado can be devastating, preparing ahead of time is the best way to ensure you and your family’s safety. Please read the following questions about tornado safety, answered by Prosper Emergency Management Coordinator Kent Bauer. Q: During s evere weather, what does the Prosper Fire Department do? A: We monitor the weather alerts sent out by the National Weather Service. Because we are not meteorologists, we do not interpret any sort of storms or any sort of warnings. Instead, we pass along the information we receive from the National Weather Service to our residents through social media, storm sirens and Smart911 Rave weather warnings. Q: What does a Tornado Watch mean? A: Tornadoes are possible. Remain alert for approaching storms. Watch the sky and stay tuned to NOAA Weather Radio, commercial radio or television for information. Q: What does a Tornado Warning mean? A: A tornado has been sighted or indicated by weather radar and you need to take shelter immediately. Q: What is the reason for setting off the Outdoor Storm Sirens? A: To alert those who are outdoors that there is a tornado or another major storm event headed Prosper’s way, so seek shelter immediately. I f you are outside and you hear the sirens go off, do not call 9-1-1 to ask questions about the warning.
    [Show full text]
  • 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.
    [Show full text]
  • More Observations of Small Funnel Clouds and Other Tubular Clouds
    3714 MONTHLY WEATHER REVIEW VOLUME 133 PICTURE OF THE MONTH More Observations of Small Funnel Clouds and Other Tubular Clouds HOWARD B. BLUESTEIN School of Meteorology, University of Oklahoma, Norman, Oklahoma (Manuscript received 14 March 2005, in final form 20 May 2005) ABSTRACT In this brief contribution, photographic documentation is provided of a variety of small, tubular-shaped clouds and of a small funnel cloud pendant from a convective cloud that appears to have been modified by flow over high-altitude mountains in northeast Colorado. These funnel clouds are contrasted with others that have been documented, including those pendant from high-based cumulus clouds in the plains of the United States. It is suggested that the mountain funnel cloud is unique in that flow over high terrain is probably responsible for its existence; other types of small funnel clouds are seen both over elevated, mountainous terrain and over flat terrain at lower elevations. 1. Introduction which the benign funnel clouds occur so that if they are observed, severe weather warnings are not issued. Fur- Bluestein (1994) and others (e.g., Doswell 1985, p. thermore, the small funnel clouds are of interest in their 107; McCaul and Blanchard 1990) have documented, in own right because their dynamics are not well under- the plains of the United States, small funnel clouds pen- stood, and they have not been discussed in the litera- dant from convective clouds whose updrafts appear to ture to the much greater extent that the dynamics of be rooted above the boundary layer. Above many of tornadoes have (e.g., Davies-Jones 1986).
    [Show full text]
  • The Lagrange Torando During Vortex2. Part Ii: Photogrammetry Analysis of the Tornado Combined with Dual-Doppler Radar Data
    6.3 THE LAGRANGE TORANDO DURING VORTEX2. PART II: PHOTOGRAMMETRY ANALYSIS OF THE TORNADO COMBINED WITH DUAL-DOPPLER RADAR DATA Nolan T. Atkins*, Roger M. Wakimoto#, Anthony McGee*, Rachel Ducharme*, and Joshua Wurman+ *Lyndon State College #National Center for Atmospheric Research +Center for Severe Weather Research Lyndonville, VT 05851 Boulder, CO 80305 Boulder, CO 80305 1. INTRODUCTION studies, however, that have related the velocity and reflectivity features observed in the radar data to Over the years, mobile ground-based and air- the visual characteristics of the condensation fun- borne Doppler radars have collected high-resolu- nel, debris cloud, and attendant surface damage tion data within the hook region of supercell (e.g., Bluestein et al. 1993, 1197, 204, 2007a&b; thunderstorms (e.g., Bluestein et al. 1993, 1997, Wakimoto et al. 2003; Rasmussen and Straka 2004, 2007a&b; Wurman and Gill 2000; Alexander 2007). and Wurman 2005; Wurman et al. 2007b&c). This paper is the second in a series that pre- These studies have revealed details of the low- sents analyses of a tornado that formed near level winds in and around tornadoes along with LaGrange, WY on 5 June 2009 during the Verifica- radar reflectivity features such as weak echo holes tion on the Origins of Rotation in Tornadoes Exper- and multiple high-reflectivity rings. There are few iment (VORTEX 2). VORTEX 2 (Wurman et al. 5 June, 2009 KCYS 88D 2002 UTC 2102 UTC 2202 UTC dBZ - 0.5° 100 Chugwater 100 50 75 Chugwater 75 330° 25 Goshen Co. 25 km 300° 50 Goshen Co. 25 60° KCYS 30° 30° 50 80 270° 10 25 40 55 dBZ 70 -45 -30 -15 0 15 30 45 ms-1 Fig.
    [Show full text]
  • Nasa.Gov Determine Their Severity Now Are a Little Less Mysterious
    Print Close Related Links January 12, 2004 - (date of web publication) For more information contact: Elvia Thompson A "HOT TOWER" ABOVE THE EYE CAN MAKE HURRICANES Headquarters, Washington STRONGER (Phone: 202/358-1696) They are called hurricanes in the Rob Gutro Atlantic, typhoons in Goddard Space Flight Center, Greenbelt, the West Pacific, Md. and tropical (Phone: 301/286-4044) cyclones worldwide; but wherever these For information about the TRMM Satellite storms roam, the on the Internet, visit: forces that http://trmm.gsfc.nasa.gov determine their http://www.eorc.nasda.go.jp/TRMM severity now are a little less mysterious. NASA scientists, For information about NOAA's National Hurricane Center click here. using data from the Tropical Rainfall For information about Hurricane Measuring Mission Item 1 (TRMM) satellite, Bonnie, click here. have found "hot High resolution image tower" clouds are associated with tropical cyclone intensification. Viewable Images Owen Kelley and John Stout of NASA's Goddard Space Flight Center, Greenbelt, Md., and George Mason University will present their findings at the American Meteorological Society annual meeting in Seattle on Monday, January 12. Caption for Item 1: AN UNUSUALLY DEEP CONVECTIVE TOWER IN Kelley and Stout define a "hot tower" as a rain cloud that reaches at HURRICANE BONNIE AS BONNIE least to the top of the troposphere, the lowest layer of the atmosphere. INTENSIFIED It extends approximately nine miles (14.5 km) high in the tropics. These towers are called "hot" because they rise to such altitude due to This TRMM Precipitation Radar overflight of Hurricane Bonnie shows an 11 mile the large amount of latent heat.
    [Show full text]
  • Winds:Towards Better Weather Forecasts in Africa
    WINDS:TOWARDS BETTER WEATHER FORECASTS IN AFRICA. KINYODA G. G Kenya Meteorological Department P.o box 30259, Nairobi. KENYA Tel: 56 78 80/Fax: 56 78 88 ABSTRACT: Poor operational meteorological network in Africa has for a long time continued to make weather forecasting difficult. Data extracted from the operational meteorological satellites is therefore vital information for this region. This paper describes, compares and evaluates the operational use of wind information disseminated via the MDD system to Africa; focussing at the Regional Specialized Meteorological Centre (RSMC), Nairobi, the African Centre of Meteorological Applications for Development (ACMAD), Niamey (Niger) and the Drought Monitoring Centre (DMC) in Nairobi. 1. INTRODUCTION 4. SCOPE In describing and evaluating the use of the wind Meteorological services rely heavily on timely information received via the MDD system, this paper :- dissemination of meteorological observations and derived • Discusses briefly the main weather/climate infuencing products.In many parts of the world telecommunications factors in Africa. This is considered important in the links provided by the WMO Global Telecommunications understanding of how the wind information is analysed, System (GTS), which is also used for interchange of interpreted and incorporated into the weather forecasts. meteorological data are satisfactory. However, extensive • Verifies qualitatively, the analysed wind information areas still suffer from a high degree of unreliability. Africa against the validating "truth" provided by a is particularly affected by the unreliability of the GTS. coresponding Meteosat imagery, over a short period. Fortunately, this region lies within the field of view of the • Finally, the MDD’s mission performance is evaluated Meteosat satellite.
    [Show full text]
  • An Experimental Analysis of Resilience in Urban Flood Management in the Taipei Basin
    Resilience in Space: An experimental analysis of resilience in urban flood management in the Taipei Basin Hsu Chia Sui Email: [email protected] Thesis Supervisor: Kimberly Nicholas Email: [email protected] A thesis submitted in partial fulfillment of the requirements of the Lund University International Master’s Programme in Environmental Studies and Sustainability Science (LUMES), May 2011 Abstract The existing paradigm of flood management in the Taipei Basin prioritizes structural measures over non-structural measures. This strategy is not sufficiently flexible, particularly in light of increasingly frequent extreme weather. Resilience theory is concerned with the capacity of a system to absorb disturbance and retain its same functions. This study offers new insight by conceptualizing resilience in urban flood management. In particular, it demonstrates to what extent resilience theory as used in research on social-ecological systems was useful in developing a better plan for urban flood management. The study comprises a resilience assessment of flood management in Taipei based on guidelines in a workbook for scientists published by the Resilience Alliance. This study identified the external shocks to the flood management system in the Taipei Basin include typhoons, evidence of increasingly frequent extreme weather, groundwater mining and resulting land subsidence, and rapid urbanization. This study also includes a historical profile of major flooding and hydraulic projects from 1960 to 2010 and analyzes phases in terms of an adaptive cycle. The study concludes that resilience theory was an effective approach to investigating external shocks and stress to the system. Furthermore, the qualitative approach to apply resilience was a useful discourse for envisioning a better urban flood management system.
    [Show full text]