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| + | ='''Setting up the monitoring network'''= | ||
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| + | Before setting up a monitoring network a decision has to be made on the type of network that is appropriate for the country or region at hand. This chapter outlines the practical steps to set up such a network given the choice made in the [[Chapter6|previous chapter]]. | ||
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| <blockquote> | <blockquote> | ||
| ='''Setting up the monitoring network'''= | ='''Setting up the monitoring network'''= | ||
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| * A reasonably stable stream of data on de decadal basis (or daily, hourly basis) should reach the crop forecasting unit. | * A reasonably stable stream of data on de decadal basis (or daily, hourly basis) should reach the crop forecasting unit. | ||
| * Stations should be evenly spread in crop growing areas. It does not make sense to include five stations in a 10 by 10 kilometer area (this is often the case in a capital city) | * Stations should be evenly spread in crop growing areas. It does not make sense to include five stations in a 10 by 10 kilometer area (this is often the case in a capital city) | ||
| + | * To monitor crops in a water balance model, the following data are needed for the selected stations: | ||
| + | ** Rainfall (actual and normal) | ||
| + | ** PET (Potential evapotranspiration) | ||
| + | ** Crops (which crops are planted and where they can be found) | ||
| + | ** Planting dates for crops (PLD) | ||
| + | ** Cycle length for all the crops (CYC) | ||
| + | ** Water Holding Capacity (WHC) of the soil. | ||
| + | ** Percentage Effective Rainfall (EFR) | ||
| + | ** Pre-season Crop coefficient (usually around 0.15) | ||
| + | ** Irrigation data including bund height (when applicable). | ||
| + | |||
| The following fields for every station are needed: | The following fields for every station are needed: | ||
| Line 24: | Line 40: | ||
| # Province (optional) | # Province (optional) | ||
| # District (optional) | # District (optional) | ||
| + | |||
| </blockquote> | </blockquote> | ||
Revision as of 11:55, 16 June 2006
Setting up the monitoring network
Before setting up a monitoring network a decision has to be made on the type of network that is appropriate for the country or region at hand. This chapter outlines the practical steps to set up such a network given the choice made in the previous chapter.
Setting up the monitoring network
Before setting up a monitoring network a decision has to be made on the type of network that is appropriate for the country or region at hand. This chapter outlines the practical steps to set up such a network given the choice made in the previous chapter.
A station-based network
Most countries have an extensive network of meteorological stations. The most important types of monitoring stations are :
- Synoptic stations. These stations provide hourly data on a real-time basis. Usually these data are fed into the global GTS system of WMO. Most of these stations provide weather data that enable users to calculate the Penman-Monteith reference evaporation (ET0). A subset of these stations do upper-air observations, which is less interesting for agrometeorological purposes.
- Realtime Rainfall stations. These stations monitor rainfall and send in their data to the National Meteorological Office once a day.
- Off-line rainfall stations that send in their daily data once a month or even once a year. These stations are important for climatic studies and the provision of normal data.
Which stations are to be included in the crop monitoring network? A few criteria:
- The station should be in an area where the monitoring crops are located.
- A reasonably stable stream of data on de decadal basis (or daily, hourly basis) should reach the crop forecasting unit.
- Stations should be evenly spread in crop growing areas. It does not make sense to include five stations in a 10 by 10 kilometer area (this is often the case in a capital city)
- To monitor crops in a water balance model, the following data are needed for the selected stations:
- Rainfall (actual and normal)
- PET (Potential evapotranspiration)
- Crops (which crops are planted and where they can be found)
- Planting dates for crops (PLD)
- Cycle length for all the crops (CYC)
- Water Holding Capacity (WHC) of the soil.
- Percentage Effective Rainfall (EFR)
- Pre-season Crop coefficient (usually around 0.15)
- Irrigation data including bund height (when applicable).
The following fields for every station are needed:
- ID (national or international number)
- Name (spelling is sometimes an issue)
- Longitude
- Latitude
- Altitude
- Province (optional)
- District (optional)