Session Three: Factors That Influence Weather in South Africa
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Extreme Climatic Characteristics Near the Coastline of the Southeast Region of Brazil in the Last 40 Years
Extreme Climatic Characteristics Near the Coastline of the Southeast Region of Brazil in the Last 40 Years Marilia Mitidieri Fernandes de Oliveira ( [email protected] ) Federal University of Rio de Janeiro: Universidade Federal do Rio de Janeiro Jorge Luiz Fernandes de Oliveira Fluminense Federal University Pedro José Farias Fernandes Fluminense Federal University, Physical Geography Laboratory (LAGEF), Eric Gilleland National, Center for Atmospheric Research (NCAR) Nelson Francisco Favilla Ebecken Federal University of Rio de Janeiro: Universidade Federal do Rio de Janeiro Research Article Keywords: ERA5 Reanalysis data, Non-parametric statistical tests, severe weather systems, subtropical cyclones Posted Date: June 7th, 2021 DOI: https://doi.org/10.21203/rs.3.rs-159473/v1 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License 1 Extreme climatic characteristics near the coastline of the Southeast region of Brazil in the last 40 years Marilia Mitidieri Fernandes de Oliveira1, Jorge Luiz Fernandes de Oliveira2, Pedro José Farias Fernandes3, Eric Gilleland4, Nelson Francisco Favilla Ebecken1 1Federal University of Rio de Janeiro, Civil Engineering Postgraduate Program-COPPE/UFRJ, Center of Technology, Rio de Janeiro 21945-970, Brazil 2Fluminense Federal University, Geography Postgraduate Program, Department of Geography, Geoscience Institute, Niterói 24210-340, Brazil 3Fluminense Federal University, Physical Geography Laboratory (LAGEF), Department of Geography, Niterói 24210-340, -
NOTES and CORRESPONDENCE Synoptic-Scale Controls of Summer
15 FEBRUARY 2006 NOTES AND CORRESPONDENCE 613 NOTES AND CORRESPONDENCE Synoptic-Scale Controls of Summer Precipitation in the Southeastern United States JEREMY E. DIEM Department of Anthropology and Geography, Georgia State University, Atlanta, Georgia (Manuscript received 15 October 2004, in final form 11 August 2005) ABSTRACT Past climatological research has not quantitatively defined the synoptic-scale circulation deviations re- sponsible for anomalous summer-season precipitation totals in the southeastern United States. Therefore, the objectives of this research were to determine the synoptic-scale controls of wet and dry multiday periods during the summer within a portion of the southeastern United States as well as to assess the linkages between synoptic-scale circulation and multidecadal variations in precipitation characteristics for the study domain. Daily precipitation data from 30 stations for June, July, and August from 1953 to 2002 were converted into 13-day totals. Using standardized principal components analysis (PCA), the study domain was divided into three precipitation regions (i.e., South, Northwest, and Northeast). Wet and dry periods for each region were composed of the top 56 and bottom 56 thirteen-day periods. Composite circulation maps for 500 and 850 mb revealed the following: wet periods were generally associated with an upper-level trough over the interior southeastern United States coincident with strong lower-tropospheric flow into the South- east from the Gulf of Mexico, and dry periods were characterized by ridges or anticyclones over the midwestern and southeastern United States coupled with weak lower-tropospheric flow. Many of the wet periods had surface fronts. Over the 50-yr period, increased precipitation was significantly correlated with increased occurrences of midtropospheric troughs over the study domain. -
1 Climatology of South American Seasonal Changes
Vol. 27 N° 1 y 2 (2002) 1-30 PROGRESS IN PAN AMERICAN CLIVAR RESEARCH: UNDERSTANDING THE SOUTH AMERICAN MONSOON Julia Nogués-Paegle 1 (1), Carlos R. Mechoso (2), Rong Fu (3), E. Hugo Berbery (4), Winston C. Chao (5), Tsing-Chang Chen (6), Kerry Cook (7), Alvaro F. Diaz (8), David Enfield (9), Rosana Ferreira (4), Alice M. Grimm (10), Vernon Kousky (11), Brant Liebmann (12), José Marengo (13), Kingste Mo (11), J. David Neelin (2), Jan Paegle (1), Andrew W. Robertson (14), Anji Seth (14), Carolina S. Vera (15), and Jiayu Zhou (16) (1) Department of Meteorology, University of Utah, USA, (2) Department of Atmospheric Sciences, University of California, Los Angeles, USA, (3) Georgia Institute of Technology; Earth & Atmospheric Sciences, USA (4) Department of Meteorology, University of Maryland, USA, (5) Laboratory for Atmospheres, NASA/Goddard Space Flight Center, USA, (6) Department of Geological and Atmospheric Sciences, Iowa State University, USA, (7) Department of Earth and Atmospheric Sciences, Cornell University, USA, (8) Instituto de Mecánica de Fluidos e Ingeniería Ambiental, Universidad de la República, Uruguay, (9) NOAA Atlantic Oceanographic Laboratory, USA, (10) Department of Physics, Federal University of Paraná, Brazil, (11) Climate Prediction Center/NCEP/NWS/NOAA, USA, (12) NOAA-CIRES Climate Diagnostics Center, USA, (13) Centro de Previsao do Tempo e Estudos de Clima, CPTEC, Brazil, (14) International Research Institute for Climate Prediction, Lamont Doherty Earth Observatory of Columbia University, USA, (15) CIMA/Departmento de Ciencias de la Atmósfera, University of Buenos Aires, Argentina, (16) Goddard Earth Sciences Technology Center, University of Maryland, USA. (Manuscript received 13 May 2002, in final form 20 January 2003) ABSTRACT A review of recent findings on the South American Monsoon System (SAMS) is presented. -
Synoptic-Scale Controls of Fog and Low Clouds in the Namib Desert: Response to Reviewer 1
Synoptic-scale controls of fog and low clouds in the Namib Desert: Response to Reviewer 1 Hendrik Andersen, Jan Cermak, Julia Fuchs, Peter Knippertz, Marco Gaetani, Julian Quinting, Sebastian Sippel, and Roland Vogt contact: [email protected] We would like to thank reviewer 1 for her/his careful review of the manuscript and her/his constructive criticism and valuable comments. Comments by the referee are colored in black, our replies or comments are colored in blue and italics. Using a 14-year period of reanalysis grids and backward trajectories, this study examines the impact of large-scale dynamics and thermodynamics on fog and low clouds (FLCs) over Namib. Specifically, the authors’ focus on two seasons when different FLC types are observed due to different synoptic-scale regimes. A main finding is that the mean sea level pressure (MSLP) field differs notably between clear and FLC days. To this end, the authors’ use a statistical model and MSLP fields to provide skillful prediction of FLCs up to one day in advance. A new conceptual model of the two different FLC regimes is developed to summarize findings and aid in future studies related to FLCs over Namib. In general, the scientific purpose is justified, the findings are important, and the paper is well-written; however, I do have concerns about some of the methods used. Overall, I think that the results are interesting and worthy of publication, and at this stage I suggest acceptance subject to major revisions. Major/general comments: 1. Use of MSLP, 2 m temperature, and 10 m winds to characterize synoptic-scale conditions This study relies on the assumption that near-surface (boundary layer) meteorological variables – specifically MSLP, 2 m temperature, and 10 m horizontal wind components – are representative of the large-scale dynamics. -
Weather, Current and Routing Brief the Clipper 11/12 Round the World
Weather, Current and Routing Brief The Clipper 11/12 Round the World Race Prepared for the Race Skippers by Simon Rowell 27th April 2011 1. Leg One - Europe to Rio de Janeiro (early August to mid September) 4 1.1. The Route 4 1.2. The Weather 6 1.2.1. The Iberian Peninsula to the Canaries 6 1.2.2. The Canaries 10 1.2.3. The Canaries to the ITCZ, via the Cape Verdes 11 1.2.4. The ITCZ in the Atlantic 13 1.2.5. The ITCZ to Cabo Frio 16 1.3. Currents 18 1.3.1. The Iberian Peninsula to the Equator 18 1.3.2. The Equator to Rio 20 2. Leg 2 – Rio de Janeiro to Cape Town (mid September to mid October) 22 2.1. The Route 22 2.2. The Weather 22 2.3. Currents 27 3. Leg 3 – Cape Town to Western Australia (October to November) 29 3.1. The Route 29 3.2. The Weather 30 3.2.1. Southern Indian Ocean Fronts 34 3.3. Currents 35 3.3.1 Currents around the Aghulas Bank 35 3.3.2 Currents in the Southern Indian Ocean 37 4. Leg 4 –Western Australia to Wellington to Eastern Australia (mid November to December) 4.1. The Route 38 4.2. The Weather 39 4.2.1. Cape Leeuwin to Tasmania 39 4.2.2. Tasmania to Wellington and then to Gold Coast 43 4.3. Currents 47 5. Leg 5 – Gold Coast to Singapore to Qingdao (early January to end of February) 48 5.1. -
Short-Term Relationships Between Winter Temperatures and Cardiac Disease Mortality in Cape Town
3. Miller NF, Forde OH, Fhelle SS, Mjos OD. The Tromso heart study: high density lipoprotein and coronary heart disease: a prospective case-control study. Lancet 1977; 1: 965-967. Short-term relationships 4. Maciejko JJ, Holmes OR, Kottke BA, Zinsmeister AR, Dinh OM, Mao SJT. ~ A·p·olipoprotein AI as a marker for angiographically assessed coronary artery disease. N Engl J Med 1963; 309: 385-389. between winter 5. Ordovas JM. Schaefer FJ. Salem 0, et al. Apolipoprotein AI gene polymorphism associated with premature coronary artery disease and familial hypoalphalipo proteinemia. N Engl J Med 1986; 314: 671-677. temperatures and cardiac 6. Kessling A, Rajput-Williams J, Bainton 0, et al. DNA polymorphisms of the apolipoprotein All and AI-CIII-AIV genes: a study in men selected for differences in high density lipoprotein cholesterol concentration. Am J Hum Genet 1988; 42: disease mortality in Cape 458-467. 7. Karathanasis SK. Apolipoprotein multigene family: tandem organisation of apolipoprotein AIV. AI and CIII genes. Proc Natl Acad Sci USA 1986; 82: Town 6374-6378. 8. Humphries S. Kessling A, Wile 0, Jeenah M. Miller N. Variation at the apolipoprotein gene loci contributes to the determination of plasma apo AI and J. C. Heunis, J. Olivier, D. E. Bourne HDL-cholesterol levels in patients with coronary artery disease and healthy controls. In: Miller NE, ed. High Density Lipoproteins and Atherosclerosis 11. Amsterdam: Elsevier Science Publishers, 1989: 87-94. 9. Kessling A, Quellette S, Bouffard O. et al. Patterns of association between The short-term relationship between winter temperatures genetic variability in apolipoprotein S, apo Al-CIII-AIV, and cholesterol ester transfer protein gene regions and quantitative variation in lipid and lipoprotein and cardiac disease mortality in Cape Town was traits: influence of gender and exogenous hormones. -
Study & Master Geography Grade 12 Teacher's Guide
Ge0graphy CAPS Grade Teacher’s Guide Helen Collett • Norma Catherine Winearls Peter J Holmes 12 SM_Geography_12_TG_CAPS_ENG.indd 1 2013/06/11 6:21 PM Study & Master Geography Grade 12 Teacher’s Guide Helen Collett • Norma Catherine Winearls • Peter J Holmes SM_Geography_12_TG_TP_CAPS_ENGGeog Gr 12 TG.indb 1 BW.indd 1 2013/06/116/11/13 7:13:30 6:09 PMPM CAMBRIDGE UNIVERSITY PRESS Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São Paulo, Delhi, Mexico City Cambridge University Press The Water Club, Beach Road, Granger Bay, Cape Town 8005, South Africa www.cup.co.za © Cambridge University Press 2013 This publication is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. First published 2013 ISBN 978-1-107-38162-9 Editor: Barbara Hutton Proofreader: Anthea Johnstone Artists: Sue Abraham and Peter Holmes Typesetter: Brink Publishing & Design Cover image: Gallo Images/Wolfgang Poelzer/Getty Images ………………………………………………......…………………………………………………………… ACKNOWLEDGEMENTS Photographs: Peter Holmes: pp. 267, 271, 273 and 274 Maps: Chief Directorate: National Geo-spatial Information: Department of Rural Development and Land Reform: pp. 189, 233–235 and 284–289 ………………………………………………......…………………………………………………………… Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate. Information regarding prices, travel timetables and other factual information given in this work are correct at the time of first printing but Cambridge University Press does not guarantee the accuracy of such information thereafter. -
North and South American Low-Level Jets
American Low Level jetS A Scientific Prospectus and Implementation Plan North and South American Low-Level Jets Draft, March 2001 Prepared by Julia Nogues-Paegle and Jan Paegle (University of Utah, USA) with con- tributions from Michael Douglas (NOAA/NSSL, USA), Matilde Nicolini, Carolina Vera (University of Buenos Aires, Argentina), Jose Marengo (CPTEC, Brazil), Rene Garreaud (University of Chile, Chile), James Shuttleworth (University of Arizona, USA), C. Roberto Mechoso (UCLA, USA) and E. Hugo Berbery (University of Mary- land, USA). TABLE OF CONTENTS Executive Summary 5 1. What is the ALLS program? 6 2. Why the American Jets? 9 3. Science Objectives 11 3.1 Identify LLJ events and variability 11 3.1.1. North America 11 3.1.2. South America 14 3.2 Quantify LLJ contributions to the hydrological cycle 16 3.2.1. North America 16 3.2.2. South America 17 3.3 Determine plateau effects 19 3.3.1. North America 19 3.3.2. South America 19 3.4 Develop and validate theories on LLJ generation and variability 21 3.4.1. North America 21 3.4.2. South America 22 3.4.3 Local and remote influences on ALLS in relation 23 to droughts and floods 4. Implementation Plan 26 4.1 Numerical Modelling 26 4.2 Diagnostic Studies 29 4.3 Field Component of ALLS 30 4.3.1. Region of focus for the ALLS South American Field Program 32 4.3.2. Radiosonde network 33 4.3.3. Pilot balloon observations 35 4.3.4. Wind profiler observations 35 4.3.5. -
Identification of Processes Driving Low-Level Westerlies in West
1JUNE 2014 P O K A M E T A L . 4245 Identification of Processes Driving Low-Level Westerlies in West Equatorial Africa WILFRIED M. POKAM Department of Physics, Higher Teacher Training College, University of Yaounde 1, and Center for International Forestry Research, Central Africa Regional Office, Yaounde, Cameroon CAROLINE L. BAIN,ROBIN S. CHADWICK, AND RICHARD GRAHAM Met Office Hadley Centre, Exeter, United Kingdom DENIS JEAN SONWA Center for International Forestry Research, Central Africa Regional Office, Yaounde, Cameroon FRANCOIS MKANKAM KAMGA University of Mountain, Bangangte, Cameroon (Manuscript received 8 August 2013, in final form 16 January 2014) ABSTRACT This paper investigates and characterizes the control mechanisms of the low-level circulation over west equatorial Africa (WEA) using four reanalysis datasets. Emphasis is placed on the contribution of the di- vergent and rotational circulation to the total flow. Additional focus is made on analyzing the zonal wind component, in order to gain insight into the processes that control the variability of the low-level westerlies (LLW) in the region. The results suggest that the control mechanisms differ north and south of 68N. In the north, the LLW are primarily a rotational flow forming part of the cyclonic circulation driven primarily by the heat low of the West African monsoon system. This northern branch of the LLW is well developed from June to August and disappears in December–February. South of 68N, the seasonal variability of the LLW is controlled by the heating contrast between cooling associated with subsidence over the ocean and heating over land regions largely south of the equator, where ascent prevails. -
Rava (Risk and Vulnerability Assessment for the Western Cape)
Rava (Risk and Vulnerability Assessment for the Western Cape) Disaster Mitigation for Sustainable Livelihoods Programme (DiMP) University of Cape Town Executive Summary Institutional context In April 2002, the Provincial Tender Board approved Phase I of a Risk and Vulnerability Assessment Model for the Western Cape Province, to be undertaken jointly by the Universities of the Free State and Cape Town. Phase I of the RAVA Project represents the first step in a comprehensive risk assessment of likely disaster threats. It focuses on identifying natural and other hazards relevant to the Western Cape as well as the most appropriate institutional sources for reliable hazard information. This report addresses the interim reporting requirement to: complete an audit of hazard/disaster risk information sources and organisations relevant to the Western Cape, including the nature of information storage formats, and prepare a draft report indicating all identified natural and human-induced disasters. The UCT component reported here primarily reflects natural and other threats, and excludes information on droughts and floods. These two phenomena were analysed by the University of the Free State. Methodology To collect and consolidate relevant data/information on relevant natural and human-induced hazards in the Western Cape, three data gathering strategies were adopted: • Participatory consultation with key stakeholders took place through three distinct processes: Individual consultation with representatives from 32 municipalities Consultative -
Grade 12 Geography Climatology Answer Book
SECONDARY SCHOOL IMPROVEMENT PROGRAMME (SSIP) 2019 REVISED GEOGRAPHY REVISED ANSWERBOOK CLIMATOLOGY ANSWER BOOK GRADE 12 TABLE OF CONTENTS SESSION TOPIC PAGE 1 MID-LATITUDE CYCLONE 2 TROPICAL CYCLONES 3 ANTICYCLONIC MOVEMENT OVER SA 4 MICROCLIMATE – VALLEY / URBAN CLIMATE AND WEATHER ANSWERS SESSION 1 - TOPIC 1: MID-LATITUDE CYCLONES ANSWERS FOR SECTION B: CAPS EXAM QUESTIONS ON MID-LATITUDE CYCLONES: CAPS QUESTIONS Midlatitude cyclone (November 2014) Answers 1.1. 1.1.1 Cyclone family (1)Family of depressions (1) 1.1.2.(a) showers warm air/sector cold r shape of front air/sector [ANY FOUR] (4 x 1) (4) (b) Decrease in temperature (2) Change in the wind direction (backing) (2) Heavy rainfall with thunder and lightning (2) Increase in air pressure (2) Increase in cloud cover (cumulonimbus clouds) (2) Increase in wind speed (2) Decrease in humidity (2) Possibility of snowfall (2) [ANY ONE] (1 x 2) (2) 1.1.3. Weather conditions and reasons Air temperature: 27°C (2) Cold air descending from the high pressure warms adiabatically to create a high temperature on the surface (2) Dew point temperature: -12°C (2) Dry area/winter therefore less evaporation (2) Subsiding air reduces humidity (2) Wind direction: NW/WNW (2) Air diverging in an anticlockwise direction around the high pressure (2) Wind speed: 5 knots (2) Gentle pressure gradient (the isobars are far apart) (2) Cloud cover: (1/8) (2) Very little cloud cover as the area is dry and had low levels of moisture (2) Subsiding air heats up and does not condense (2) Low relative humidity (2) Precipitation No precipitation (2) Subsiding air does not condense (2) Limited cloud cover (2) Large difference between air temperature and dew point temperature (2) [ANY TWO WEATHER CONDITIONS AND REASONS] (4 x 2) (8) 2015 Feb 2.1 2.1.1. -
A Climatology of the Coastal Low in the SW Cape
A CLIMATOLOGY OF THE COASTAL LOW IN THE SW CAPE BY C.M. HEYDENRYCH THESIS SUBMITTEDUniversity IN FULFILLMENT of Cape OF THE Town REQUIREMENTS TOWARDS A MSc DEGREE IN THE DEPARTMENT OF ENVIRONMENTAL AND GEOGRAPHICAL SCIENCE UNIVERSITY OF CAPE TOWN 1987 , ; i. j ,: ; :·~ r ; f !i' , , I,. t..., fr ; L2 • [:: <, J4 • ~· ~ f~ :". · ·: ~,, ' . ~ l'f; f '. U I • r • \_~c _-.____:_ .. --- The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgement of the source. The thesis is to be used for private study or non- commercial research purposes only. Published by the University of Cape Town (UCT) in terms of the non-exclusive license granted to UCT by the author. University of Cape Town i ABSTRACT The Coastal Low is a shallow cyclonic mesoscale weather 'disturbance' which migrates around the southern African subcontinent on a fairly regular basis. It is generated and maintained by the synoptic scale circulations. The movement and surface characteristics have been well documented by a number of authors but few detailed studies have been undertaken on its vertical structure in southern Africa. In addition to this, most of the previous work has been of a meteorological nature. This study has concentrated on a more climatic approach in its investigation of the vertical and· surface features of the Coastal Low as it migrates through the South Western (SW) Cape. The SW Cape is a •transition region' for the migration of the Coastal Low; situated between the west and south coasts with a distinct local climate due to the complex topography of the region.