WORLD METEOROLOGICAL ORGANIZATION TECHNICAL NOTE No. 201 AGROMETEOROLOGY RELATED TO EXTREME EVENTS by H.P. Das, T.I. Adamenko, K.A. Anaman, R.G. Gommes and G. Johnson (CAgM-XI Working Group on Agrometeorology Related to Extreme Events) WMO-No. 943 Secretariat of the World Meteorological Organization - Geneva - Switzerland The World Meteorological Organization The World Meteorological Organization (WMO), of which 185* States and Territories are Members, is a specialized agency of the United Nations. The purposes of the Organization are: (a) To facilitate world-wide cooperation in the establishment of networks of stations for the making of meteorological observations as well as hydrological and other geophysical observations related to meteorology, and to promote the establishment and maintenance of centres charged with the provision of meteorological and related services; (b) To promote the establishment and maintenance of systems for the rapid exchange of meteorological and related information; (c) To promote standardization of meteorological and related observations and to ensure the uniform publication of observations and statistics; (d) To further the application of meteorology to aviation, shipping, water problems, agriculture and other human activities; (e) To promote activities in operational hydrology and to further close cooperation between Meteorological and Hydrological Services; and (f) To encourage research and training in meteorology and, as appropriate, in related fields and to assist in coordinating the international aspects of such research and training. (Convention of the World Meteorological Organization, Article 2) The Organization consists of the following: The World Meteorological Congress, the supreme body of the Organization, brings together the delegates of Members once every four years to determine general policies for the fulfilment of the purposes of the Organization, to approve long-term plans, to authorize maximum expenditures for the following financial period, to adopt Technical Regulations relating to international meteorological and operational hydrological practice, to elect the President and Vice-Presidents of the Organization and members of the Executive Council and to appoint the Secretary-General; The Executive Council, composed of 36 directors of national Meteorological or Hydrometeorological Services, meets at least once a year to review the activities of the Organization and to implement the programmes approved by Congress; The six regional associations (Africa, Asia, South America, North and Central America, South-West Pacific and Europe), composed of Members, coordinate meteorological and related activities within their respective Regions; The eight technical commissions, composed of experts designated by Members, study matters within their specific areas of competence (technical commissions have been established for basic systems, instruments and methods of observation, atmospheric sciences, aeronautical meteorology, agricultural meteorology, marine meteorology, hydrology, and climatology); The Secretariat, headed by the Secretary-General, serves as the administrative, documentation and information centre of the Organization. It prepares, edits, produces and distributes the publications of the Organization, carries out the duties specified in the Convention and other Basic Documents and provides secretariat support to the work of the constituent bodies of WMO described above. ________ * On 1 July 2002 WORLD METEOROLOGICAL ORGANIZATION TECHNICAL NOTE No. 201 AGROMETEOROLOGY RELATED TO EXTREME EVENTS by H.P. Das, T.I. Adamenko, K.A. Anaman, R.G. Gommes and G. Johnson (CAgM-XI Working Group on Agrometeorology Related to Extreme Events) WMO-No. 943 Secretariat of the World Meteorological Organization – Geneva – Switzerland 2003 © 2003, World Meteorological Organization ISBN: 92-63-10943-5 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. CONTENTS Page FOREWORD ............................................................................................................................. VII SUMMARY (English, French, Russian and Spanish)............................................................... IX LIST OF CONTRIBUTORS .................................................................................................... XIII CHAPTER 1 — INTRODUCTION (by H.P. Das) ................................................................. 1 1.1 Definition of extreme events ......................................................................................... 1 1.2 Types of extreme climatic events ................................................................................... 1 1.3 Agrometeorological data related to extreme events ...................................................... 1 1.4 Extreme events and agricultural production ................................................................. 3 1.5 Socio-economic impact of extreme events .................................................................... 4 1.6 Prevention and preparedness ......................................................................................... 5 1.7 Rehabilitation ................................................................................................................ 5 References .................................................................................................................................. 6 CHAPTER 2 — AGROMETEOROLOGICAL ASPECTS OF DROUGHT AND DESERTIFICATION (by H.P. Das).......................................................................................... 7 2.1 Drought ........................................................................................................................... 7 2.1.1 Introduction ................................................................................................... 7 2.1.2 Drought and famine ....................................................................................... 7 2.1.3 Drought concepts, definitions and quantifications........................................ 8 2.1.4 Data availability ............................................................................................. 9 2.1.5 Causes of drought ........................................................................................... 10 2.1.6 Spatial and temporal aspects of drought ........................................................ 11 2.1.7 Impact of drought ........................................................................................... 11 2.1.8 Forecasting drought ........................................................................................ 13 2.1.9 Drought detection, monitoring and early warning ........................................ 13 2.1.10 Adaptation and adjustments to drought ........................................................ 16 2.1.11 Drought management: mitigation, preparedness and policy ......................... 17 2.1.12 Summary and conclusion ............................................................................... 19 2.2 Desertification................................................................................................................. 19 2.2.1 Introduction ................................................................................................... 19 2.2.2 Definition of desertification ........................................................................... 20 2.2.3 Distribution of desertification ........................................................................ 21 2.2.4 Desertification trends ..................................................................................... 21 2.2.5 Physical processes of desertification............................................................... 23 2.2.6 Causes of desertification................................................................................. 23 2.2.7 Desertification and feedback mechanism....................................................... 26 2.2.8 Desertification and development ................................................................... 27 2.2.9 Monitoring and assessment of desertification................................................ 27 2.2.10 Recovery and control of desertification ......................................................... 28 2.2.11 Summary and conclusion ............................................................................... 29 2.2.12 Suggestions and recommendations ................................................................ 30 References .................................................................................................................................. 30 CHAPTER 3 — INCIDENCE, PREDICTION, MONITORING AND MITIGATION MEASURES OF TROPICAL CYCLONES AND STORM SURGES (by H.P. Das)............. 35 3.1 Introduction.................................................................................................................... 35 3.2 Geographical distribution of tropical cyclones .............................................................. 35 3.3 Regional categorization of tropical cyclones and their intensity ................................... 37 3.4 Characteristics of a tropical cyclone..............................................................................