Improving Weather Forecasting Services in India

By Dr. Shailesh Nayak
Secretary, Ministry of Earth Sciences, Govt. Of India

New Delhi, Jan 19, 2011 (Washington Bangla Radio / PIB-India) Recognizing the importance of predictions of weather, climate and hazards for the societal benefit services, the Ministry of Earth Sciences had focused its activities in an integrated manner towards improving the understanding of the earth system (atmosphere, hydrosphere, cryosphere, geosphere and biosphere). The purpose of studying the different components holistically has been to understand better the interactions among them, influenced by both natural processes and anthropogenic activities, leading to improved forecasting services. The Earth System Science Organization functions on a mission mode where significant achievements have been made during the last one year in the major missions.

Weather Prediction and Services

Short-term (up to 3 days ) and medium-range (up to 5-7 days) forecast are being generated using numerical weather prediction models. A new high resolution GFS (Global Forecast System) based on the T382L64 model and its associated data assimilation including radiance assimilation has been made operational during the year. This has significantly improved spatial resolution of 35 km. Besides, a meso-scale model WRF model (27 km) forecast was implemented in real time for the prediction of weather systems like tropical depressions, thunderstorms, etc. Very high resolution (9 km and 3 km) nested WRF runs have been done for exclusive case studies of severe weather. The accuracy obtained is about 70-75 per cent. A Global model assimilation utilizing 4 D VAR is being done on an experimental basis. The basic forecast parameters include rainfall, wind speed, wind direction, humidity and temperature. Another important component installed this year is the development of an end-to-end forecasting system that connects the various instruments and observing systems, their real time transmission and linkage to a central data processing system and their utilization in numerical models, thus providing a state-of-the art IT-based forecasting environment to all forecasters throughout the country. This involves integrating all observations and overlaying them on model outputs and synoptic charts along with proper visualization and dissemination of weather forecasts to the end users. The parameters for cyclone forecast issued in 24 and 36 hours in advance are landfall, track prediction, intensity.

Agromet Services

About 60 per cent of the population depends on agriculture and thus weather-based agricultural advisories are critical. Short-term predictions of rainfall, maximum and minimum temperature, total cloud cover, surface relative humidity and wind, based on the Multi-Model Ensemble (MME) having a 35 km grid for 130 Agromet field units are routinely provided. These advisories provide information on suitable times for sowing crops, need –based application of fertilizers, pesticides, insecticides, efficient irrigation and harvest. Bi-weekly bulletins for more than 575 districts have been issued for farmers. Such bulletins at State and National levels have also been generated for policy decisions. These advisories are disseminated through print, electronic media and multilingual Web portals. The development of location-based services through mobiles has been very successful, currently, over 1.2 million farmers have subscribed to this service.

Aviation Services-Fog Forecast

Fog affects aviation services severely during winters. The monitoring, forecasting and dissemination of the intensity and duration of the fog is crucial. Runway Visibility Recorders (RVRs) provide visibility conditions along all runways. Met Reports (forecast of met conditions for 9 to 30 hours) every 30 minutes, fog forecasts for the next 6 hours and the outlook for the next 12 hours are provided. Trend forecasts for the next 2 hours have been introduced. Information is provided through websites, SMS, IVRS, phone, fax, etc,. The accuracy of the forecast was 94 and 86 per cent for December and January 2009-10, respectively, substantially improved from 2008-09 which was 74 and 58 per cent for December and January, respectively.

Environmental Service

A network for air pollution monitoring stations has been set up at Allahabad, Jodhpur, Kodaikanal, Minicoy, Mohanbari, Nagpur, Port Blair, Pune, Srinagar and Visakhapatnam to collect rain samples for chemical analysis and measurement of atmospheric turbidity with the objective of documenting the long-term changes in the composition of trace species of the atmosphere. Specific services pertaining to the assessment of likely air pollution impacts arising from thermal power generation, industries and mining activities have also been provided. Atmospheric diffusion models developed for carrying air quality impacts of multiple sources located in different climatic and geographical conditions are being utilized for site-selection of industries and adoption of air pollution control strategies. Weather and Air Quality Forecasting for the Commonwealth Games (CWG) – 2010 has been accomplished through the commission of AWS, DWR and other observing systems.

Fishery Advisory

About 7 million people living along the Indian coastline, which spans more than 7500 km, are dependent on fishing for their livelihood. Only 15 per cent of total fish production is from aquaculture, hence we continue to depend on captured fishery. Locating and catching fish is challenging as fish stocks dwindle and move further offshore, thus increasing the search time, cost and effort. Reliable and timely forecast on the potential zones of fish aggregation help to reduce the time and effort spent in searching fishing grounds, for the socio-economic benefit of the fishing community. Fish are known to react to changes in the surrounding environment and migrate to areas where favorable conditions in terms of seawater temperature, salinity, color, visibility dissolved oxygen levels, etc,. exist. Sea Surface Temperature (SST), the indicative parameter of the environment is most easily observed on satellite images. The availability of food is an important factor which controls their occurrence, abundance and migration in the sea. Chlorophyll-a is an indicator of the availability of food for fish. These forecasts are routinely given thrice-a-week and are valid for a period of three days along with the ocean state forecast. These advisories are given in nine local languages and English through the web email, fax, radio and TV as well as electronic display boards in fishing harbors and information kiosks. It has been estimated that 40,000 fishermen use these advisories. It saves a lot of fuel and time (60-70 per cent) and thus allows for efficient fishing. It has been estimated that the success rate is around 80 per cent.

Ocean State Forecasting

Efforts to develop real-time forecasts for the Indian Ocean using numerical models are at the initial stage. The Indian Ocean Forecasting System (INDOFOS) launched in February 2010 includes forecasts of ocean wave height, wave direction, Sea Surface Temperature (SST), surface currents, Mixed Layer Depth (MLD) and depth of 200 C isotherm for the next five days at six hourly intervals. The beneficiaries of INDOFOS are traditional and mechanized fishermen, the maritime boards, the Indian Navy, the Coast Guard shipping companies and petroleum industries, energy industries and academic institutions. Location-specific models for wave forecasts for Gujarat, Maharashtra, Karnataka and Pondicherry have been set up which are being extensively used by port authorities.

Mining Technology

India has been planning to harness ocean mineral resources. This requires the development of a set of three pieces of equipment, viz., In-situ soil tester, Remotely Operable Vehicles (ROV), and a deep sea crawler. The in-situ soil tester for measuring sea bed soil properties and the ROV were successfully tested in April, 2010 at a depth of 5300 m. Complete hardware and software for the instrumentation and control systems were developed indigenously. The crawler to collect nodules has been tested at a depth of 450 m off the Malvan coast. A coring system with 100 m core collecting capability up to a 3000 m water depth has been developed. Demonstration trails are currently underway. This equipment is being development as a part of technology developed for harnessing Gas Hydrate.

Hatchery Technology

The development of hatchery technology of commercially important species is a major area for the providing alternate employment to fishermen. Black lip pearl oysters are being produced at the Andaman hatchery. Breeding and rearing technology for marine ornamental fishes, viz., eight species of Clown fishes and ten species of Damsel fishes has been perfected. Techniques for captive breeding, larva development and the mass culture of juveniles on four species of gastropods have been perfected. The technology has been transferred to local fishermen.

Climate Variability and Change

This program addresses various scientific issues relating to climate change including the impact on sectors like health, agriculture and water. In an effort to explore and assess targeted science-facets of climate change that are highly relevant to the Indian region along with their global linkages, climate modeling and dynamics, regional aspects of global climate change using instrumental and proxy climate records, short-term and long-term climate diagnostics and predictions are some of the major programs that have been undertaken. The sea level rise on the Indian cost was about 1.3 mm/year up to 2000. The rate of rise after 2004 is higher. Climate products such as major anomalous climate event, high-resolution daily gridded rainfall data (10 x 10 ) and (0.50 x 0.50), high-resolution daily gridded temperature data (10 x 10), and climatologically summaries for districts and states have been generated.

Polar Science

The First Scientific Expedition was conducted successfully by an 8-member team to the South Pole in November 2010. The team had covered a total distance of 4680 km. during the expedition, the scientists used ground-penetrating radar to study the bedrock hidden beneath the ice, collected ice cores to study snow chemistry, and studied the glacial landscapes.

(PIB Features)