CLIMWAT is a climatic database to be used in combination with the computer program CROPWAT and allows the ready calculation of crop water requirements, irrigation supply and irrigation scheduling for various crops for a range of climatological stations worldwide.

The CLIMWAT database includes data from a total of 3262 meteorological stations from 144 countries. CLIMWAT is published as Irrigation and Drainage paper No 49 in 1994 and includes a Manual with description of the use of the database with CROPWAT The data are contained in five diskettes included in the publication and can be ordered as FAO Irrigation and Drainage Paper 49 through the FAO Sales and Marketing Group (Price US$ 35)

Publications-sales@fao.org

The CLIMWAT data can be also downloaded from the FAO-FTP server contained in six continental files:

• Asia and the Pacific
  
• Sub-Saharan Africa
  
• Near East and North Africa
  
• Europe
  
• South America
  
• Caribbean Island and Central America

Each continental file contains country files which can be unzipped in suitable directories.

The original database was compiled by the Agrometeorological Group of FAO's Environment and Natural Resources Service and has been converted into a format suitable for use by CROPWAT.

The climatological data included are maximum and minimum temperature, mean daily relative humidity, sunshine hours, windspeed, precipitation and calculated values for reference evapotranspiration and effective rainfall.

The reference evapotranspiration has been calculated for all stations according the Penman Monteith method, as recommended by the FAO Expert Consultation held in Rome, May 1990. Further details on the methodology are provided in the following paper: Revised FAO Methodology for Crop Water Requirements.

The database is meant as a practical tool to assist irrigation and agricultural specialists in the planning and management of irrigated and rainfed agriculture in combination with the CROPWAT program.

To assist the user of CLIMWAT in the use of the database and the CROPWAT program, the various procedures to set up the system and to address the selected climatic stations are presented in the manual. Examples are presented to show how the various data can be addressed and used for planning and management of irrigated and rainfed agriculture.

The impressive efforts of the FAO Agrometeorological Group in compiling the data from various sources all over the world are acknowledged with appreciation. Any queries or comments on the data source should therefore be referred to:

The Coordinator Agrometeorological Group Research and Technology Development Division Food and Agriculture Organization Viale delle Terme di Caracalla 00100 Rome, Italy

Rene.Gommes@fao.org

The manual and diskettes can be ordered as FAO Irrigation and Drainage Paper No. 49 by writing to:

Sales and Marketing Group Food and Agriculture Organization Viale delle Terme di Caracalla 00100 Rome, Italy

Publications-sales@fao.org

or through local FAO Sales Agents.

For all further technical information queries can be directed to:

The Water Resources, Development and Management Service of FAO, Viale delle Terme di Caracalla, 00100 Rome, Italy Tel: +(39) 06 57055541, Fax: (39-06) 57056275

The Water Management and Irrigation Systems Group