Historically, more emphasis has been placed on the response component of drought management, with little or no attention to mitigation, preparedness, prediction or monitoring. With the present awareness of the effects of ongoing climate change and global warning, the importance of a meteorological early warning system becomes more apparent.
Since drought is a natural calamity, awareness only might not be sufficient to overcome this occurrence hence a system that handles both awareness and management of this disaster upon occurrence is imperative.Granted that there are numerous ways of combating drought, a well-structured system of integrating all these methodologies is required. Such as system has the advantage of being able to anticipate areas that may cut back on water supply requirements, ability to run more frequent forecasts of the expected water supply and also allow more accurately calibrated forecasts. All these seemingly hectic problems can be easily solved with an integrated computer based system. This documentation seeks to solve the drought management problem by design of a Drought Early Warning and Management System (DEWMS).
The Ministry of Agriculture, under which the Department of Meteorology falls, shall best manage this system. Drought prone areas shall be the primary beneficiaries advisories and warnings generated by the DEWMS. Other areas deemed to need primary drought awareness and response are areas under irrigation whose operations would be gravely affected by prolonged dry weather conditions. SYSTEM SPECIFICATION The inherent objective of the envisioned system is to manage and co-ordinate all government efforts in drought preparedness and awareness and subsequent disaster responses.In the process, other secondary objectives such as provision of data for research or educational purposes and employment creation for information technology analysts shall be realized.
The system's course-grain functional requirements shall invariably centre on a well-structured hierarchical database, decentralised independent sub-systems and a central controller system. All sub-systems shall invariably exhibit certain characteristics as real-time performance, reliability and efficiency hence the utmost care shall be taken in procurement of supporting hardware and operating system platforms.The system's ambient environment shall be a Linux platform for system dependability and efficiency, and seamless integration with the communication system. On the flipside, data redundancy and replication, unnecessary straining of the system controller and general system overloads shall be meticulously avoided.
Data mining in various forms shall be carried out and a centralized database management system designed. This shall facilitate ready and quick access of data to aid in trend analysis and accurate drought forecasting.The system shall be functionally devolved in data centres around the country namely synoptic agro-meteorological stations (meteorological stations concerned with data collection for agricultural research), fully automated ordinary weather and Service Specific Stations (SSS) set-up at places of specific interest like marine weather stations, major water reservoirs and hydroelectric plants. Automated Topographical Layouts shall be at hand to aid in mapping hence the use of a Geographical Information System to aid in demarcation of drought prone areas.The National Meteorological Department shall install national surveillance radar and act as a national weather watch station. Once data obtained is analysed and a drought forecast, the system shall issue a National Drought Watch to warn of an imminent drought.
Once the drought actually happens, a National Drought Alert shall be launched symbolising the onset of drought. The drought alert shall be categorised into various levels depending on drought intensity with the worst-case scenario being graded as level three. The management system shall hence aid in provision of information on trend, monitoring and impact assessment of drought.SYSTEM MODEL The system's main sub-systems shall the national grid of data collection centres, the communication system and the centralised system controller. These main sub-systems shall be multi-functional and their discrete nature shall help realize the system's emergent properties. FUNCTIONAL SYSTEM COMPONENTS SENSOR COMPONENTS This sub-system is involved with collection of data from the system's ambient environment.
The synoptic stations shall be equipped with automated conventional operational instruments and equipment with an aim of upgrading the level of data acquisition.All major rivers in the country shall be fitted with stream gauges at strategic places provided there is an ordinary weather station within a one-kilometre radius. At irrigation schemes, automated humidity sensors shall be installed that shall get the humidity levels at intervals of six hours. Other critical data collection centres shall be water artificial reservoirs. Automated stations shall be located at each major water reservoir. The more stations there are, the more finite and accurate the average control shall be.
For monitoring of cloud cover satellite photos shall be obtained from the international weather station on a daily basis. The radar system shall be installed at the national meteorological headquarters. This radar shall provide information about precipitation and also determine wind speed. Each station shall have a decentralised database that shall store data collected at the station level.
A centralised database shall be located at the National Meteorological Department headquarters. The decentralised databases shall serve to reduce contention for the national database and hence increase efficiency.