1、ASCE STANDARDANSI/ASCE/EWRI42-17Standard Practice for the Design, Conduct, and Evaluation of Operational Precipitation Enhancement ProjectsASCE STANDARD ANSI/ASCE/EWRI42-17Standard Practice for theDesign, Conduct, and Evaluationof Operational PrecipitationEnhancement ProjectsPUBLISHED BY THE AMERICA
2、N SOCIETY OF CIVIL ENGINEERSLibrary of Congress Cataloging-in-Publication DataNames: American Society of Civil Engineers.Title: Standard practice for the design, conduct, and evaluation of operational precipitationenhancement projects.Description: Reston, Virginia : American Society of Civil Enginee
3、rs, 2016. | Series: ASCEstandard | Series: ANSI/ASCE/EWRI ; 42-16 | Includes bibliographical references and index.Identiers: LCCN 2016019974 | ISBN 9780784414408 (soft cover : alk. paper) | ISBN9780784479766 (pdf)Subjects: LCSH: Rain-makingStandardsUnited States. | Precipitation (Meteorology)Modicat
4、ionStandardsUnited States.Classication: LCC QC928.6 .O64 2016 | DDC 551.68/77021873dc23 LC record availableat https:/lccn.loc.gov/2016019974Published by American Society of Civil Engineers1801 Alexander Bell DriveReston, Virginia, 20191-4382www.asce.org/bookstore | ascelibrary.orgThis standard was d
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12、issions” link.Errata: Errata, if any, can be found at http:/dx.doi.org/10.1061/9780784414408.Copyright 2017 by the American Society of Civil Engineers.All Rights Reserved.ISBN 978-0-7844-1440-8 (soft cover)ISBN 978-0-7844-7976-6 (PDF)Manufactured in the United States of America.24 23 22 21 20 19 18
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15、Rules forStandards Committees, which are available at www.asce.org.Errata, addenda, supplements, and interpretations, if any, for thisstandard can also be found at www.asce.org.This standard has been prepared in accordance with recog-nized engineering principles and should not be used without theuse
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17、nation ofpatent rights or risk of infringement is entirely his or her ownresponsibility.A complete list of currently available standards is available inthe ASCE Library (http:/ascelibrary.org/page/books/s-standards).iiiThis page intentionally left blankCONTENTSPREFACE . ixACKNOWLEDGMENTS . xi1 INTRO
18、DUCTION TO PRECIPITATION ENHANCEMENT PROJECTS. . . . . . . . . . . . . . . . . . . . . . . 11.1 Scope of Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2 Historical Perspective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
19、. . . . . . . . . . . . . . . 11.2.1 Orographic Clouds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2.2 Convective Clouds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.3 Status of Precipitation Enhancement Technolog
20、y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.4 Appropriate ASCE/EWRI Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.5 Appropriate ASCE/EWRI Manuals of Professional Practice . . . . . . . . . . . . . . . . . . . . . . . . . . 22 SCIENTI
21、FIC BASIS OF NATURAL PRECIPITATION EFFICIENCY AND ITS MODIFICATION . . . . . . . . 32.1 Precipitation Augmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42.1.1 Cloud Seeding to Increase Precipitation Efciency of Primarily Stratiform and Orographic Clou
22、ds 42.1.2 Seeding to Enhance Precipitation Efciency of Individual Cold Convective Clouds . . . . . . . . 42.1.2.1 Seeding to Enhance Development of Individual Cold Convective Cloud PrecipitationProcesses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42.1.2.2 Comp
23、lexities of Seeding Individual Cold Convective Clouds . . . . . . . . . . . . . . 52.1.2.3 Expansion of Seeding Concepts to Cloud Clusters and Mesoscale Systems. . . . . . . 52.1.3 Seeding to Enhance the Efciency of the Warm Convective Cloud Precipitation Process . . . . . 52.2 Technological Advance
24、s. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 THE DESIGN OF OPERATIONAL PRECIPITATION ENHANCEMENT PROJECTS . . . . . . . . . . . . . . . 73.1 Denition of Project Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25、. 73.1.1 Basic Project Area Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73.1.2 Initial Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83.1.3 Climatology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
26、 . . . . . . . . . . . . . . . . 83.2 Seeding Agent Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83.2.1 Silver Iodide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.2.2 Dry Ice. . . . . . . . . . .
27、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.2.3 Other Ice Nucleants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.2.4 Hygroscopic Agents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
28、.2.5 Quality Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103.2.5.1 Glaciogenic AgentsAgI. 103.2.5.2 Hygroscopic Agents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103.3 Targeting and Delivery Methods . . . . . . . . . .
29、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103.3.1 Airborne Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103.3.1.1 Glaciogenic Seeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113.3.1.2 Cloud Base Seedi
30、ng . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113.3.1.3 In-Cloud Seeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113.3.1.4 Cloud Top Seeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113.3.1.5 Hygroscopic Se
31、eding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123.3.2 Ground Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133.3.2.1 Glaciogenic Seeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133.3.2.2 H
32、ygroscopic Seeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133.3.3 Advantages and Disadvantages of Aerial and Ground Systems . . . . . . . . . . . . . . . . . . . 133.4 Meteorological Data Collection and Instrumentation . . . . . . . . . . . . . . . . . . . . . . . . .
33、. . . . . 143.4.1 Real-Time Decision Making and Monitoring Instrumentation . . . . . . . . . . . . . . . . . . . . 143.4.1.1 Available Weather Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143.4.1.2 Project Precipitation Gauges. . . . . . . . . . . . . . . . . . . . . . .
34、. . . . . . . . . 153.4.1.3 Project Rawinsonde Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163.4.1.4 Real-Time Liquid Water Observations . . . . . . . . . . . . . . . . . . . . . . . . . . 17Standard Practice for the Design, Conduct, and Evaluation of Operational Precipita
35、tion Enhancement Projects v3.4.1.5 Streamow Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173.4.1.6 Snow Sample Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173.4.1.7 Numerical Cloud Modeling . . . . . . . . . . . . . . . . . . . .
36、. . . . . . . . . . . . 173.4.1.8 Predictive Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183.4.1.9 Diagnostic Modeling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183.5 Deployment of Cloud Seeding Equipment . . . . . . . . . . . . . . .
37、 . . . . . . . . . . . . . . . . . . . . 183.5.1 Dispersion Rates of Cloud Seeding Materials in Winter and Summer Clouds . . . . . . . . . . . 193.5.1.1 Airborne Cloud Seeding Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.5.2 Ground-Based Cloud Seeding Modes. . . . . . . . . .
38、 . . . . . . . . . . . . . . . . . . . . . . . 203.6 Legal Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.6.1 Potential for Litigation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.6.2 Regulation
39、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213.6.3 Interstate Compacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213.7 Environmental Concerns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
40、 . . . . . . . . . . . . 213.7.1 Redistribution of Precipitation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223.7.2 Seeding Agent Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 OPERATIONS OF PRECIPITATION ENHANCEMENT PROJECT
41、S . . . . . . . . . . . . . . . . . . . . . . . . 234.1 The Operations Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234.2 Personnel Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234.2.1 Meteo
42、rological Staff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234.2.2 Cloud-System Treatment Pilots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234.2.3 Direction of Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
43、. . . . . . . . . . . 234.2.4 Support Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244.3 Operational Decision Making . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244.3.1 Chronology. . . . . . . . . . . . . . .
44、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244.3.2 Opportunity Recognition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244.3.2.1 Aircraft Flight Crews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244.3.2.1.1 Summer Seed
45、ing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244.3.2.1.2 Winter Seeding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254.3.2.2 Ice Nuclei Treatment by Ground-Based Generators . . . . . . . . . . . . . . . . . . . 254.3.2.2.1 Summertime Seeding. . . . . . .
46、. . . . . . . . . . . . . . . . . . . . . . . 254.3.2.2.2 Winter Seeding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254.4 Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254.5 Safety Considerations . . . . . . . .
47、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264.5.1 Safety of Field Personnel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264.5.1.1 Radar Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264.5.1.
48、2 Use, Handling, and Storage of Seeding Agents . . . . . . . . . . . . . . . . . . . . . 264.5.1.3 Severe Weather Hazards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264.5.1.4 Aircraft Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274.5.2
49、 Seeding Suspension Criteria. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274.6 Public Relations, Information, and Involvement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275 EVALUATION OF PRECIPITATION ENHANCEMENT PROJECTS . . . . . . . . . . . . . . . . . . . . . . . . 295.1 Project Design Constraints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295.1.1 Randomized versus Nonrandomized Projects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295.1.2 Selecti
