Despite considerable technological advancement and improved irrigation facilities, Indian farmers are still dependent on monsoons. Inclement weather events such as, cold and heat waves, hail, squalls, tropical storms severely affect agricultural production. The malevolent effect of adverse weather can be partially reduced if predicted in advance and farmers suitably advised.
At present public weather forecasts are issued for one to two days in advance. Although useful for many applications, these are inadequate for planning weather based agricultural practices as time needed for putting in place precautionary measures is longer. For the purpose of effective planning of modern agricultural practices such as sowing of weather sensitive high yield variety of seeds, need based application of fertiliser, pesticides, insecticides, efficient irrigation and harvest, weather forecasts for the period 3 to 10 days in advance are desirable. In the meteorological parlance, the time scale of 3 to 10 days is known as ‘medium range’.
Establishment of agro advisory services
India Meteorological Department (IMD) had set up its Agrometeorological division way back in 1932. The farmers’ weather bulletins were initially issued once in a day, but stepped up to twice by the 1990’s. The Agromet Advisory Services (AAS) of IMD, with a network of 23 units at present, issues biweekly bulletins in vernacular, disseminated through the radio, television, newspapers and website. The National Centre for Medium Range Weather Forecasting (NCMRWF) was established under Department of Science and Technology in early 1988 to develop operational and reliable AAS for the farming community. The NCMRWF in collaboration with the IMD, Indian Council of Agricultural Research and State Agricultural Universities has been providing AAS for 127 agro climatic zones with each zone covering about 2 to 4 districts. After the creation of a new Ministry of Earth Sciences (MoES), the two services of IMD and NCMRWF have now been integrated and established at IMD.
Present operational set up
At present, the agro climatic zone specific forecast is being prepared in quantitative terms for rainfall, cloud cover, maximum temperature, minimum temperature, wind speed and wind direction. The forecast is disseminated to the AAS units in real time using the internet or telefax. On receipt the field unit prepares the forecast in vernacular which are then relayed to the farmers. Each AAS unit also identifies about 50 progressive farmers with whom extension workers are always in touch to obtain continuous feedback on worthiness of the bulletin and suggestions for improvement. In addition to the farmers, these bulletins are also provided to local agriculture, horticulture, irrigation, soil conservation and animal husbandry departments. Since 2004, a weekly agro advisory bulletin has been started during monsoons. A web based agro advisory system was also implemented in 2004.
Creating district level agro advisory service
Although successful and useful in terms of benefits accrued, the present AAS is not adequate to deal with sustainable production issues related to different farming systems. The present system lacks observations on spatial variability in farm operations due to non availability of information on weather, soil condition, sowing decision taken by farmer, irrigation, fertiliser and chemical application etc., within the zone. Thus the system is not able to include weather based advisory for every farming system in the zone. The MoES is now planning to expand the farm advisory network from agro climatic zone scale to the district level. The DAAS, likely to be implemented from June, 2008 has several innovative features.
Weather Observations: Setting up of district level observation systems through Automatic Weather Station (AWS) will form the basis for refining medium range weather forecast. Information on various high impact weather events such as extreme temperatures, heavy rains, floods and strong winds etc., will now be included. Establishment of about 550 additional AWS and 1350 Automatic Rain Gauge (ARG) stations falls in the first phase of the modernisation plan. With this, almost every district in the country will have at least one AWS and 2 ARG stations. IMD already has 125 AWS and a large number of manual observatories.
Medium range weather forecast: Accuracy of weather forecast calls for availability of precise weather predictions for every district in the country. India being a tropical country, weather prediction is a stupendous task. Location specific weather forecasts in tropics suffer errors, unlike extra tropical places where weather systems are generally well behaved. With continuous interaction and support from national and international scientists, the country has witnessed an improvement in accuracy in recent years. The NCMRWF has implemented a high resolution global model – T 254, along with several meso scale models in recent years.
Agro advisory: DAAS is expected to provide enormous opportunity in crop planning and management. This, availability and use of spatial data/information at sub district scale on crop stage and condition, soil and other interactive parameters like soil moisture etc., at regular interval are also expected to be available which will be used to address the prevailing variability in the farming system and make the farm advisory more efficient, objective and meaningful. This needs the development of dynamic model based Decision Support System (DSS) on crop, pest and disease and livestock management for use of spatial data to increase the timeliness of planting, spraying operations, irrigation applications, fertiliser applications, etc. The advisories is also envisaged to serve as early warning system for alerting producers to various weather events such as extreme temperatures, heavy rains, floods and strong winds.
Information dissemination system: Timely dissemination of weather observations, forecasts, AAS bulletins and other weather related information to the end users is critical for their beneficial use in farm management or otherwise. Mass media tools will be exploited to evolve a system through which the various agencies of mass communication work towards the dissemination of advisory bulletins. A reliable communication facility of National Informatics Centre (NIC) operating at district and sub district levels for uninterrupted information transfer may be set up. For better adaptability among the farmers, farmers’ participatory approach need to be strengthened by way of organising farmer fairs and farmer awareness meet etc., more frequently.