DOCSLIB.ORG

Winter Cloud Seeding Potential on the Mogollon

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Winter Cloud Seeding Potential on the Mogollon WINTER CLOUD SEEDIN POTENTIAL ON THE MOGOLLON RIM FINAL REPORT PREPARED FOR ARIZONA DEPARTMENT OF WATER RESOURCES UNDER IGA-88-6189-000-0051 JANUARY 1989 , U.S. DEPARTMENT OF THE INTERIOR Bureau of Reclamation Denver Research and laboratory Services DivWon Water Augmentation Group POTENTIAL ON THE EPORTPREPAREDFOR ARIZONA DEPARTMENT OF WATER RESOURCES UNDER IGA-88-6189-000-0051 03720 7. AUTHOR(S) 8. PERFORMING ORGANIZATION REPORT NO. Arlin B. Super, Edmond W. Hdroyd, Ill, and Jack T. McPartland R-89-02 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. WORK UNIT NO. Bureau of Reclamation Denver Office 11. CONTRACT OR GRANT NO. Denver CO 80225 IGA-88-6189-000-0051 13. TYPE OF REPORT AND PERIOD - COVERED 12. SPONSORING AGENCY NAME AND ADDRESS I State of Arizona I Department of Water Resources 1 15 South 15th Avenue 14. SPONSORING AGENCY CODE R 15. SUPPLEMENTARY NOTES I Microfiche and hard copy available at the Denver Office, Denver, Colorado. 16. ABSTRACT Natural doud and precipitation processes were investigated on the Mogollon Rim of Arizona during midJanuary to midMarch of 1987 and 1988. The primary goal was to evaluate the cloud seeding potential of winter storms prior to attempting any seeding. It was crucial to monitor the availability of supercooled CLW (cloud liquid water) required for precipitation development, and this was accomplished with a ground-based microwave radiometer and instrumented aircraft. Other measurements of importance included doud depth and structure, atmospheric stabilii, winds, doud ice particles and water droplets, and surface precipitation. The field measurements were put in the context of large-scale weather patterns using standard weather maps and satellite photographs. A secondary goal involved evaluation of ground-based seeding simulated by transport and diffusion experiments using a tracer gas. Several important findings emerged from the various analyses of the data Cloud liquid water was available during portions of most storm episodes. The flux of liquid water passing over the crestline during a 4-month winter was estimated at 30 to 100 percent of the mean annual runoff from the study areas. Thus, the raw material required for successful cloud seeding was available in reasonable abundance. The majority of the total CLW flux for each season was produced during a few large storms that were efficient in producing snowfall during portions of their lifetimes but quite inefficient during other periods. The total flux for both seasons was approximately equally divided between 326 hours (85 percent of all hours) with vertically integrated CLW amounts less than 0.20 mm and 59 hours (15 percent) with amounts between 0.20 and 0.65 mm. The amount of CLW produced by local storms or isolated clouds was limited. The transport hddision studies revealed that plumes of ground-based seeding material could usually fill most of the lowest kilometer of doudy air passing over the crest during periods with stratiform douds. However, this zone was often too warm for significant ice nucleation with conventional types of silver iodide and generators. Airaaft seeding would likely be required for a large fraction of the Arizona storm clouds. Recommendations are mdfor future experiments designed to document the physical chain of events following pmicular seeding treatments. 17. KEY WORDS AND DOCUMENT ANALYSIS DEscR lPToRs-- Weather modification/ doud seed / precipitationaugmenta,tkm/ precipitation enhancement/ artificial seeding/ cloud physics omg~bdpuds/w mdedItquid water/ doud li "id water liquid water content/ ice crystalsf snow/ preetp~tatlon~se tracking/ transport and dqkusion/ ~~s/ b. I NTIF ERS-- ~o~ollon'Rim/H y Jack Hanna n Meadow/ WieMountains/ Fla staff/ &he/ F& / Cooonhlo ~ational%st/drBSCOttBercd( National Forest/ Camp \Berde/ .. &f~ld!!%k!!p @lB COWRR: 0402.1 SRIM: 18. DISTRIBUTION STATEMENT 19. SECURITY CLASS Pl. NO. OF PAGE (THIS REPORT) Available fmm the National Technical Information Servlce, Operations u~c~~SSl~l~D- Division. 5285 Port Royal Road. Springfield. Virginia 22161. 20. SECURITY CLASS 22. PRICE173 ITUIS PAGE) WINTER CLOUD SEEDING POTENTIAL ON THE . MOGOLLON RtM FINAL REPORT PREPARED FOR ARIZONA DEPARTMENT OF WATER RESOURCES UNDER tGA-88-6189-0004051 Arlin B. Super Edmond W. Holroyd, Ill Jack T. McPartland Water Augmentation Group Research and Laboratory Services Division Denver Office Denver, Colorado January 1989 UNITED STATES DEPARTMENT OF THE INTERIOR * BUREAU OF RECLAMATION ACKNOWLEDGMENTS The investigations discussed in this report were jointly supported by the Arizona Department of Water Resources; Bureau of Reclamation, Lower Colorado Region; Central Arizona Project Association; Central Arizona Water Conservation District; Maricopa Water District; and Salt River Project. Several other agencies provided substantial assistance in conduct of the project. Significant contributions were made by the Federal Aviation Administration: Albuquerque Air Route Traffic Control Center, Scottsdale Flight Standards District Office, and Prescott Flight Service Station; U.S. Forest Service; Apache, Coconino, Prescott, and Sitgreaves National Forests; and U.S. Department of the Interior, Office of Aircraft Services. Don Griffith, John Thompson, Bill Hauze, Rich Benner, George Wilkerson, and Marty Thorp of North American Weather Consultants made substantial contributions to the 1987 field program. Wayne Sand and George Bershinski of the University of Wyoming capably managed the research aircraft program and provided their skills as pilots. John Lease provided direction for the Bureau of Reclamation's Water Augmentation Group. Others from this group who made significant contributions include Mike Collins and Glenn Cascino who provided electronics expertise and, in particular, Bruce Boe who accomplished substantial software development and preliminary analysis in support of this work, including section 5.8. Mary Ann Trujillo made significant editing and organizational contributions to the final report. As the Nation's principal conservation agency, the Department of the Interior has responsibility for most of our nationally owned public lands and natural resources. This includes fostering the wisest use of our land and water resources, protecting our fish and wildlife, preserving the environmental and cultural values of our national parks and historical places, and providing for the enjoyment of life through outdoor recreation. The Department assesses our energyand minerai resources and works 10 assure that their development is in the best interests of all our people. The Department also has a major responsibility for American Indian reservation communities and for people who live in Island Territories under U.S. Administration. The information contained in this report regarding commercial products or firms may not be used for advertising or promotional purposes and is not to be construed as an endorsement of any product or firm by the Bureau of Reclamation. The information contained in this report was developed for the Bureau of Reclamation; no warranty as to the accuracy, usefulness, or completeness is expressed or implied. 11 EXECUTIVE SUMMARY This report documents the data collection and subsequent analyses from the first two field programs of the Arizona Snowpack Augmentation Program. The purpose of these field programs was to examine the suitability of winter clouds over the Mogollon Rim area for possible future weather modification activities aimed at increasing water supplies. Only naturally occurring cloud systems were studied during the period of this report, and no cloud seeding was conducted. Measurement programs were carried out during the mid-January to mid-March period of both 1987 and 1988. Two different primary ground-observing sites were used, both near the crest of the high terrain. During early 1987, that site was Happy Jack, south of Flagstaff, while Hannagan Meadow in the White Mountains of eastern Arizona was used in early 1988. The 1987 program was more comprehensive, including aircraft, radar, and other observations not available during 1988. One of the initial analysis efforts was to develop a storm episode classification system. In its final form, each hour of each storm was typed by the scale of the weather disturbance causing it, whether synoptic (affecting a large area) or mesoscale (affecting a local area), and by the presence or absence of significant convection; that is, whether the clouds were predominantly stratiform or convective. This dual classification provided a framework for other analyses. The most important field observations were of cloud liquid water, chiefly collected by a ground-based microwave radiometer. This relatively new instrument can continuously monitor the vertically integrated amount of cloud liquid water above it. Winter precipitation over the Mogollon Rim is produced when the normally supercooled (colder than 0 °c) cloud liquid water is converted into tiny ice particles that grow to snowflake size and settle to the surface. Consequently, it is very important to measure the cloud liquid water overhead as it is the "raw material" or "fuel" for precipitation. It is known that cloud liquid water often forms over the windward side of mountain barriers due to the uplift and associated cooling of moist air. Conversely, the cloud liquid water rapidly evaporates on the lee side due to subsidence and warming of the air, resulting in the well-known "rain shadow" effect downwind of many mountain ranges. In the Arizona studies, the radiometer was located so
Load more

Recommended publications
  • 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]
  • The Atmosphere: an Introduction to Meteorology Lutgens Tarbuck Tasa Twelfth Edition
    The Atmosphere Lutgens et al. Twelfth Edition The Atmosphere: An Introduction to Meteorology Lutgens Tarbuck Tasa Twelfth Edition ISBN 978-1-29204-229-9 9 781292 042299 ISBN 10: 1-292-04229-X ISBN 13: 978-1-292-04229-9 Pearson Education Limited Edinburgh Gate Harlow Essex CM20 2JE England and Associated Companies throughout the world Visit us on the World Wide Web at: www.pearsoned.co.uk © Pearson Education Limited 2014 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without either the prior written permission of the publisher or a licence permitting restricted copying in the United Kingdom issued by the Copyright Licensing Agency Ltd, Saffron House, 6–10 Kirby Street, London EC1N 8TS. All trademarks used herein are the property of their respective owners. The use of any trademark in this text does not vest in the author or publisher any trademark ownership rights in such trademarks, nor does the use of such trademarks imply any affi liation with or endorsement of this book by such owners. ISBN 10: 1-292-04229-X ISBN 10: 1-269-37450-8 ISBN 13: 978-1-292-04229-9 ISBN 13: 978-1-269-37450-7 British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library Printed in the United States of America Copyright_Pg_7_24.indd 1 7/29/13 11:28 AM Forms of Condensation and Precipitation TABLE 4 Types of Precipitation State of Type Approximate Size Water Description Mist 0.005–0.05 mm Liquid Droplets large enough to be felt on the face when air is moving 1 meter/second.
    [Show full text]
  • Downloaded 09/24/21 04:27 PM UTC 1512 MONTHLY WEATHER REVIEW VOLUME 146
    MAY 2018 C A V I C C H I A E T A L . 1511 Energetics and Dynamics of Subtropical Australian East Coast Cyclones: Two Contrasting Cases LEONE CAVICCHIA School of Earth Sciences, University of Melbourne, Melbourne, Australia ANDREW DOWDY Bureau of Meteorology, Melbourne, Australia KEVIN WALSH School of Earth Sciences, University of Melbourne, Melbourne, Australia (Manuscript received 27 October 2017, in final form 13 March 2018) ABSTRACT The subtropical east coast region of Australia is characterized by the frequent occurrence of low pressure systems, known as east coast lows (ECLs). The more intense ECLs can cause severe damage and disruptions to this region. While the term ‘‘east coast low’’ refers to a broad classification of events, it has been argued that different ECLs can have substantial differences in their nature, being dominated by baroclinic and barotropic processes in different degrees. Here we reexamine two well-known historical ECL case studies under this perspective: the Duck storm of March 2001 and the Pasha Bulker storm of June 2007. Exploiting the cyclone phase space analysis to study the storms’ full three-dimensional structure, we show that one storm has features similar to a typical extratropical frontal cyclone, while the other has hybrid tropical–extratropical charac- teristics. Furthermore, we examine the energetics of the atmosphere in a limited area including both systems for the ECL occurrence times, and show that the two cyclones are associated with different signatures in the energy conversion terms. We argue that the systematic use of the phase space and energetics diagnostics can form the basis for a physically based classification of ECLs, which is important to advance the understanding of ECL risk in a changing climate.
    [Show full text]
  • The Unnamed Atlantic Tropical Storms of 1970
    944 MONTHLY WEATHER REVIEW Vol. 99, No. 12 UDC 551.515.23:661.507.35!2:551.607.362.2(261) “1970.08-.lo” THE UNNAMED ATLANTIC TROPICAL STORMS OF 1970 DAVID B. SPIEGLER Allied Research Associates, Inc., Concord, Mass. ABSTRACT A detailed analysis of conventional and aircraft reconnaissance data and satellite pictures for two unnamed Atlantic Ocean cyclones during 1970 indicates that the stqrms were of tropical nature and were probably of at least minimal hurricane intensity for part of their life history. Prior to becoming a hurricane, one of the storms exhibited characteristics not typical of any of the recognized classical cyclone types [i.e., tropical, extratropical, and subtropical (Kona)]. The implications of this are discussed and the concept of semitropical cyclones as a separate cyclone category is advanced. 6. INTRODUCTION ing recognition of hybrid-type storms provides additional support for the recommendation. During the 1970 tropical cyclone season, tn7o storms occurred that were not given names at the time. The 2. UNNAMED STORM NO. I-AUG. Q3-$8, 6970 National Hurricane Center (NHC) monitored their prog- ress and issued bulletins throughout their life history but A mell-organized tropical disturbance noted on satellite they mere not officially recognized as tropical cyclones of pictures during August 8, south of the Cape Verde Islands tropical storm or hurricane intensity. In their annual post- in the far eastern tropical Atlantic, intensified to ti strong season summary of the hurricane season, NHC discusses depression as it moved westmarcl. On Thursday, August 13, these storms in some detail (Simpson and Pelissier 1971) some further intensification of the system appeared to be but thej- are not presently included in the official list of taking place while the depression was about 250 mi 1970 tropical storms.
    [Show full text]
  • Flood of August 1950 in the Waimea Area Kauai, Hawaii
    Flood of August 1950 in the Waimea Area Kauai, Hawaii > R. K. CHUN :^LOODS OF 1950 GEOLOGICAL SURVEY WATER-SUPPLY PAPER 1137-C ^repared in cooperation with the Territory of Hawaii UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1952 UNITED STATES DEPARTMENT OF THE INTERIOR Oscar L. Chapman, Secretary GEOLOGICAL SURVEY W. E. Wrather, Director For sale by the Superintendent of Documents, U. S. Government Printing Office Washington 25, D. C. - Price 15 cents (paper cover) PREFACE This report on the flood of August 1950 in Kauai, T. H., was prepared in the Surface Water Branch, J. V. B. Wells, Chief. The material was assem­ bled and the text was written by R. K. Chun, hydraulic engineer, under the immediate super­ vision of M. H. Carson, District Engineer. Base data used in this report were collected in cooperation with the Territory of Hawaii. The Weather Bureau furnished a discussion on the meteorology of the storm and a map showing the path of the hurricane. The collection of data for indirect determination of peak discharges was supervised, and the computations made, by Hollister Johnson, hydraulic engineer. Ill CONTENTS Page Introduction ..................................................... 327 Stages and discharges at stream-gaging stations ..................... 327 Waimea River near Waimea, Kauai .............................. 331 Kawaikoi Stream near Waimea, Kauai ............................ 332 Mohihi Stream near Waimea/ Kauai .............................. 333 Makaweli River near Waimea, Kauai ............................. 334 Combined discharge of Waimea and Makaweli Rivers ............... 335 Summary of flood data ............................................ 337 Flood stages and discharges ..................................... 337 Annual floods in Waimea River ................................... 337 Physical features of Kauai'........................................ 342 Meteorological features of the flood ................................ 343 Precipitation................................................... 343 Meteorology, by R.
    [Show full text]
  • Structural Transformation in Supercooled Water Controls the Crystallization Rate of Ice
    Structural transformation in supercooled water controls the crystallization rate of ice. Emily B. Moore and Valeria Molinero* Department of Chemistry, University of Utah, Salt Lake City, UT 84112-0580, USA. Contact Information for the Corresponding Author: VALERIA MOLINERO Department of Chemistry, University of Utah 315 South 1400 East, Rm 2020 Salt Lake City, UT 84112-0850 Phone: (801) 585-9618; fax (801)-581-4353 Email: [email protected] 1 One of water’s unsolved puzzles is the question of what determines the lowest temperature to which it can be cooled before freezing to ice. The supercooled liquid has been probed experimentally to near the homogeneous nucleation temperature T H≈232 K, yet the mechanism of ice crystallization—including the size and structure of critical nuclei—has not yet been resolved. The heat capacity and compressibility of liquid water anomalously increase upon moving into the supercooled region according to a power law that would diverge at T s≈225 K,1,2 so there may be a link between water’s thermodynamic anomalies and the crystallization rate of ice. But probing this link is challenging because fast crystallization prevents experimental studies of the liquid below T H. And while atomistic studies have captured water crystallization3, the computational costs involved have so far prevented an assessment of the rates and mechanism involved. Here we report coarse-grained molecular simulations with the mW water model4 in the supercooled regime around T H, which reveal that a sharp increase in the fraction of four-coordinated molecules in supercooled liquid water explains its anomalous thermodynamics and also controls the rate and mechanism of ice formation.
    [Show full text]
  • Advisory Circular 91-70A
    U.S. Department Advisory of Transportation Federal Aviation Administration Circular Subject: Oceanic and International Date: 8/12/10 AC No: 91-70A Operations Initiated by: AFS-400 Change: FOREWORD This advisory circular (AC) contains general information and guidance for operators planning oceanic flights, including authorizations needed for operations outside the continental United States. This includes Special Areas of Operation (SAO) such as North Atlantic Minimum Navigation Performance Specifications (NAT/MNPS), Reduced Vertical Separation Minimum (RVSM), Area Navigation (RNAV), and Required Navigation Performance (RNP) airspace. The dynamics of oceanic operations are such that they are constantly evolving and it is incumbent on the operators to closely monitor any changes. The Federal Aviation Administration (FAA) revised this AC to point the reader to the most current sources of international material. In many cases, the references are to a Web site. The material, however, is still found at www.faa.gov or calling a Federal Aviation Administration (FAA) navigation specialist. This AC includes specific guidance for authorizations and other FAA policy issues. A detailed study of the FAA Web site is the best source for introduction information about oceanic, international, and remote operations. John M. Allen Director, Flight Standards Service AC 91-70A 8/12/10 CONTENTS Paragraph Page CHAPTER 1. GENERAL 1-1. Purpose...........................................................................................................................1
    [Show full text]
  • Ice Particles Crystallization in the Presence of Ethanol: Investigation by Raman Scattering and X-Ray Diffraction
    Les Houches 16-26 April 2013 Ice particles crystallization in the presence of ethanol: investigation by Raman scattering and X-ray diffraction Bertrand CHAZALLON Laboratoire de Ph ysique des Lasers Atomes et Molécules Université Lille 1 PhLAM Les Houches 16-26 April 2013 Anatrac Group at PhLAM (Lille1) C.FOCSA (Pr.) M. ZISKIND (Ass. Prof) Y. CARPENTIER (Ass. Prof) S. GURLUI (Invited Prof., Univ. Iasi) S. FACQ (Dr.) At present post-doctorant at Lab. Geol. Univ/ENS LYON O. POMPILIAN (PhD) P. DELCROIX (PhD) L. DIOLOGENT (PHD) Les Houches 16-26 April 2013 http://emlg2013.univ-lille1.fr Les Houches 16-26 April 2013 Context: Freezing of aqueous droplets/solutions is also important in cryo-preservation Mechanism and action of protective additives against the freezing damage of living cells is still obscure Protective action of additives against freezing is due to a number of factors: o Ability of the cryoprotector to preserve H-bonds within the solvent upon freezing o the amount of free water molecules within a biological cells reduces during the ice growth the cryoprotectant should prevent a substantial fraction of water molecules to freeze o It should hamper the formation of large ice crystals which are likely to enlarge during warming, and may damage the cell membrane, and makes the cells leaky o Property of cryo-protector: reduction of the water-cryoprotector eutectic by maintaining a high molecular mobility at low temperature keep the biological fluids or cellular cytoplasm liquids even at low temperature Morris & Clarke, Acad. Press,
    [Show full text]
  • Ship-Based Measurements of Ice Nuclei Concentrations Over the Arctic, Atlantic, Pacific and Southern Oceans
    Atmos. Chem. Phys., 20, 15191–15206, 2020 https://doi.org/10.5194/acp-20-15191-2020 © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Ship-based measurements of ice nuclei concentrations over the Arctic, Atlantic, Pacific and Southern oceans André Welti1,6, E. Keith Bigg5,, Paul J. DeMott3, Xianda Gong1, Markus Hartmann1, Mike Harvey8, Silvia Henning1, Paul Herenz1, Thomas C. J. Hill3, Blake Hornblow9, Caroline Leck4, Mareike Löffler1,7, Christina S. McCluskey3,10, Anne Marie Rauker3, Julia Schmale2,11, Christian Tatzelt1, Manuela van Pinxteren1, and Frank Stratmann1 1Leibniz Institute for Tropospheric Research (TROPOS), Leipzig, Germany 2Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen, Switzerland 3Department of Atmospheric Science, Colorado State University, Fort Collins, CO, USA 4Department of Meteorology, Stockholm University, Stockholm, Sweden 5Elanora Heights NSW, Australia 6Finnish Meteorological Institute, Helsinki, Finland 7Deutscher Wetterdienst, Centre for Agrometeorological Research, Braunschweig, Germany 8National Institute for Water and Atmospheric Research (NIWA), Wellington, New Zealand 9BLAKE–NIWA Ambassador Programme, National Institute for Water and Atmospheric Research (NIWA), Wellington, New Zealand 10National Center for Atmospheric Research, Boulder, CO, USA 11School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland retired Correspondence: André Welti (andre.welti@fmi.fi) Received: 12 May 2020 – Discussion started: 16 June 2020 Revised: 8 October 2020 – Accepted: 15 October 2020 – Published: 8 December 2020 Abstract. Ambient concentrations of ice-forming particles concentrations of ice nuclei are observed at a certain tem- measured during ship expeditions are collected and sum- perature follows a log-normal distribution. A consequence marised with the aim of determining the spatial distribution of the log-normal distribution is that the mean concentration and variability in ice nuclei in oceanic regions.
    [Show full text]
  • Winter Cyclonic.Pdf
    University of Washington Department of Atmospheric Sciences Seattle, Washington 98195 CONTRIBUTIONS FROM THE CLOUD PHYSICS GROUP RESEARCH REPORT VI Studies of Winter Cyclonic Storms Over the Cascade Mountains (1970-71) by Peter V. Hobbs, L. F. Radke, A. B. Fraser, J. D. Locatelli, C. E. Robertson, D. G. Atkinson, R. J. Farber, R. R. Weiss, and R. C. Easter (with an Appendix by K. R. Hardy) December 1971 TABLE OF CONTENTS Preface Abstract Section 1 The B-23 Cloud Physics Research Aircraft and Airborne Instrumentation Section 2 Ground Instrumentation and Procedures Section 3 A Theoretical Model for Orographic Precipitation Section 4 Airborne Observations and Measurements Section 5 Some Results from the Ground Observations Section 6 Some Case Studies of Artificial Seeding Section 7 Radar Development and Studies Appendix Characteristics of a Weather Radar for the Investigation of Precipitation in the Pacific Northwest References Acknowledgments 1 PREFACE This report is the fourth in a series describing our studies of winter cyclonic storms, orographic clouds and precipitation over the Cascade Mountains of Washington State (the "Cascade Project"). The present report covers work carried out during 1970-71. During this period simultaneous airborne, ground and radar observations were made in a number of different synoptic situations and investigations into the effects on clouds and precipitation of seeding with artificial ice nuclei were continued. Progress was also made in developing a theoretical model to describe the flow of air over the Cascade Mountains and the growth and fall-out of precipitation from orographic clouds. Peter V. Hobbs Director, Cloud Physics Group University of Washington ABSTRACT In the first section of this report a description is given of the research aircraft and airborne instrumentation used in the Cascade Project.
    [Show full text]
  • To Marine Meteorological Services
    WORLD METEOROLOGICAL ORGANIZATION Guide to Marine Meteorological Services Third edition PLEASE NOTE THAT THIS PUBLICATION IS GOING TO BE UPDATED BY END OF 2010. WMO-No. 471 Secretariat of the World Meteorological Organization - Geneva - Switzerland 2001 © 2001, World Meteorological Organization ISBN 92-63-13471-5 NOTE The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the World Meteorological Organization concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. TABLE FOR NOTING SUPPLEMENTS RECEIVED Supplement Dated Inserted in the publication No. by date 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 CONTENTS Page FOREWORD................................................................................................................................................. ix INTRODUCTION......................................................................................................................................... xi CHAPTER 1 — MARINE METEOROLOGICAL SERVICES ........................................................... 1-1 1.1 Introduction .................................................................................................................................... 1-1 1.2 Requirements for marine meteorological information....................................................................... 1-1 1.2.1
    [Show full text]
  • Snowterm: a Thesaurus on Snow and Ice Hierarchical and Alphabetical Listings
    Quaderno tematico SNOWTERM: A THESAURUS ON SNOW AND ICE HIERARCHICAL AND ALPHABETICAL LISTINGS Paolo Plini , Rosamaria Salvatori , Mauro Valt , Valentina De Santis, Sabina Di Franco Version: November 2008 Quaderno tematico EKOLab n° 2 SnowTerm: a thesaurus on snow and ice hierarchical and alphabetical listings Version: November 2008 Paolo Plini1, Rosamaria Salvatori2, Mauro Valt3, Valentina De Santis1, Sabina Di Franco1 Abstract SnowTerm is the result of an ongoing work on a structured reference multilingual scientific and technical vocabulary covering the terminology of a specific knowledge domain like the polar and the mountain environment. The terminological system contains around 3.700 terms and it is arranged according to the EARTh thesaurus semantic model. It is foreseen an updated and expanded version of this system. 1. Introduction The use, management and diffusion of information is changing very quickly in the environmental domain, due also to the increased use of Internet, which has resulted in people having at their disposition a large sphere of information and has subsequently increased the need for multilingualism. To exploit the interchange of data, it is necessary to overcome problems of interoperability that exist at both the semantic and technological level and by improving our understanding of the semantics of the data. This can be achieved only by using a controlled and shared language. After a research on the internet, several glossaries related to polar and mountain environment were found, written mainly in English. Typically these glossaries -with a few exceptions- are not structured and are presented as flat lists containing one or more definitions. The occurrence of multiple definitions might contribute to increase the semantic ambiguity, leaving up to the user the decision about the preferred meaning of a term.
    [Show full text]