MODERNISATION OF OBSERVATIONAL NETWORK OF

INDIA METEOROLOGICAL DEPARTMENT

K. C. SAI KRISHNAN, RANJU MADAN & Dr. AJIT TYAGI

India Meteorological Department

Mausam Bhawan , Lodi Road, New Delhi- 110003

India

Telephone : / 911124611630, 911143824251, 9119999165699
Fax : / 911124611451
E-mail : /

ABSTRACT

India Meteorological Department is one of the oldest National Meteorological Services and has provided valuable services to the community by way of observational data and forecasts. The infrastructure in IMD needed to be upgraded to the latest and meet the demanding requirements of the 21st century, for which a modernisation drive was initiated in December 2007. India has an economy driven by agriculture hence the dependence of economy on weather forecast of Monsoon is high. The paper describes the attempts being made in IMD in a fast track mode, to bring the vast observational network and capabilities of the department up to international standards. This modernisation programme will implement an end to end system encompassing sensors, observation platforms, data connectivity and management, data processing using HPCS, generation of forecasts including dissemination of data to the public and various other users.

Organization

IMD was established in 1875. It is the National Meteorological Service of India and the principal government agency in all matters relating to meteorology, seismology and allied subjects. IMD headquarters are located at Delhi.

Various divisions of the organisation are as follows:

  1. Agricultural Meteorology
  2. Civil Aviation
  3. Climatology
  4. Hydrometeorology
  5. Instrumentation
  6. Meteorological Telecommunication
  7. Regional Specialised Meteorological Centre
  8. Positional Astronomy
  9. Satellite Meteorology
  10. Seismology
  11. Training

All these services need continuous improvement in accuracy and details. The present modernization plan is part of this endeavour, which encompasses updating observation system, improving connectivity with real time data acquisition, and dissemination to all centers, acquisition of High Performance Computers, improvement in numerical models and data assimilation from satellites and creating a modern IT environment for overlaying numerical model outputs with synoptic outlook, and to ultimately develop ability to forecast at district and village level.

Modernisation of the Department has been initiated in December 2007 and the first phase is to be completed by March 2011. This effort is a comprehensive programme to improve the infrastructure as well as other technical capabilities of the department so that it is at par with the best of the world. The task is daunting as the lag in technological capabilities is substantial and it is a monumental task to bridge this gap. However the modernisation programme is being vigorously implemented with continuous monitoring by the top management of IMD.

An end to end system up gradation is being done and there are primarily five segments being addressed for up gradation. These are observational infrastructure, communication, data quality processing, analysis and product generation.

The modernization scheme in Phase-I consists of the following:

  1. Networking of existing observation instruments of IMD as well as the new digital observation instruments proposed under the project,
  2. Receiving, processing and archiving of all observations in digital form at a central information processing facility at New Delhi with a backup at Pune.
  3. Dissemination of all processed information in digital form in real time to forecasters in New Delhi, Pune, all Regional Centers and selected state capitals to value add and provide customer specific products to different user communities.

For this purpose various initiatives have been taken in the department like induction of Doppler Radars, GPS Radiosondes, Automatic weather stations, and automatic raingauges in the observational network. In addition an MOU was signed with M/S Meteo France International for installation of various components such as TRANSMET, CIPS, SYNERGIE, CLISYS and METEOFACTORY.

Details of various projects being implemented under the modernisation programme of IMDin the first phase to upgrade the capabilities are given in Table-1.

Table - 1

Item /

Number

/

Item

/

Number

AWS / 550 / High Performance Computing / 2
ARG / 1350 / AWS DCS / 2
Airport systems / 26 / Information System HQ / 1
Upper Air / 25 / Forecasting System / 14
Wind Profiler / 4 / Pilot Briefing / 15
Lightning Detection / 10 / Climatology System / 2
Doppler Weather Radar / 13 / Public Weather Service system / 3
Pilot Balloon / 70 / Training / -
Radar Networking / 5 / Integration / -
AMSS / 4 / Project Management / -

MODERNISATION OF OBSERVATION SYSTEM

(a)Doppler radar network.

IMD has a network of forty radars spread all over the country as in Figure - 1 & Figure – 2. They are categorised mainly as:

(i)S Band Radars for cyclone detection installed along the coast. Eleven numbers of S – Band high power radars are located along east and west coasts of India and are used primarily for detection of cyclones approaching the Indian Coast. 5 of these radars are sate of art DWRs 4 of which were procured from M/s Gematronik, Germany and are installed at Chennai, Kolkata, Machilipatnam and Visakhapatnam. One indigenously developed DWR is installed at Sriharikota, Andhra Pradesh. Some of these radars are also used for detection of storms and other severe weather phenomenon for use in local forecasting. The effective range of these radars is 400 Km.

(ii)X Band radars for storm detection installed at airports for detection of localised phenomenon such as thunderstorms, duct storms and squalls etc. The effective range is 250 Km.

(iii) IMD also has anetwork of multipurpose radars known as MULTIMET Radars operating in the X Band. These were dual purpose radars used for tracking the radiosonde balloon as well as detection of storms. IMD has now bifurcated this category by incorporating GPS radiosonde which does not require any kind of ground based tracking facility. Hence only weather radars are being inducted into the network.

The radar network of IMD is now being upgraded with doppler weather radar technology replacing the conventional radarsIMD is also installing C band polarimetric doppler weather radars and the first two are being installed in DELHI and JAIPUR. Eventually the network in India will comprise of 55 doppler weather radars covering the entire India as shown in Figure - 3. A separate project is also being initiated for a radar network for Himalayan areas.

Figure – 1

Figure – 2

Figure – 3

(b)AWS & ARG.

India Meteorological Department is in the process of strengthening of its surface observational network in a phased manner. A network of 125 Automatic Weather Stations (AWS) was established in the year 2006-07.

Under the IMD Modernization Programme Phase-I, the network is being expanded with additional 550 AWS (Figure – 4) and 1350 Automatc Rain Gauge (ARG) stations. The sensors for parameters Air Temperature, Relative Humidity, Atmospheric Pressure, Rainfall, Wind and Global Solar Radiation are interfaced with each AWS. Out of 550 AWS planned for installation, 127 will be Agro-AWS with additional sensors for parameters soil temperature, soil moisture, leaf temperature and leaf wetness.

Out of 1350 ARGs planned for installation, 500 will have additional sensor for recording Air Temperature and Relative Humidity. Meteorologically unrepresented districts of India are being considered on priority for installation of AWS and ARG. Typically one AWS and two ARGs are planned for installation in each district.

A meso-network of 12 AWS has been established in and around National Capital Region. Meso-networks of ARGs are being established in flood prone river basins viz. Bramhaputra, Ganga, Mahanadi, Tapi, Narmada, Godavari and Krishna.

Thus, by the year 2010, a fairly uniform and dense surface observational network of 675 AWS and 1350 ARGs is expected to be available to meet operational requirements of the nation.

Figure - 4

(c)Upper air observational network

Upper air observations in IMD are being undertaken by a network of radiosondes and pilot balloon observatories. There are at present 39 observatories for radiosonde observations and 62 pilot balloon observatories, spread all over the country as shown in Figure – 5 and Figure - 6. Out of 39 radiosonde stations 37 are Radio Sonde Radio Wind stations undertaking the measurement of pressure, temperature, humidity, wind speed and direction. Two stations at Kochi and Jaipur have no wind measurement.The radiosonde measures data in the atmosphere from ground level to heights up to 30,000 m by hydrogen filled balloons, with an average rate of ascent speed between 5-6 m/s.

One indigenously developed wind profiler has been installed at Puneand is operated in experimental mode.

Figure - 5

Figure - 6

Modernisation of upper air observatories of IMD

With the aim to improve the performance of the upper air network of the department the pilot balloon observatories have been provided with semi automatic computational capability in place of the manual mode of computation. For this purpose indigenously developed hand held data logger and processor units have been supplied to all 62 pilot balloon observatories.

This has resulted in faster computation, improved quality of data because of less human intervention during the computation process and faster communication due to generation and storage of data in digital format

There was an urgent need to improve the performance of the radiosonde measurements in IMD for which 10 stations (Thiruvananthapuram, Minicoy, Goa, Port blair, Vishakhapattanam, Patna, Mohanbari, Srinagar, Chennai & Hyderabad)of the network have been equipped with high quality radiosondes using GPS technology, meeting international standards provided by M/S MODEM, France which were deployed for routine observations and have now completed one year of operational activity. Recently one Vaisala RS92SGPD radiosonde system has been installed at New Delhi and is operational since June 2010.

The use of high quality radiosondes at these stations have resulted in improvement of data quality and the data is now acceptable for numerical models. This has been acknowledged by ECMWF and NCMRWF.

Indigenous development.

As a part of the modernisation programme, indigenous development of observation systems is also being undertaken with the help of research and development organisation within the country. In this endeavour the sensors, integrated circuits, satellite capabilities, processing softwares, Doppler RADARS, windprofilers and radiosondes are being developed.

The radiosondes used in IMD have been manufactured in IMD since the beginning and under the modernisation programme the design and development of the new radiosonde also was undertaken. In this the entire radiosonde and ground system was redesigned to incorporate digital architecture, latest sensors with MEMS technology, improved telemetry and processing system. These subsystems have been developed within the country successfully and is now being put together to fabricate the complete radiosonde. Initial tests in the field have proven the reliability of thesystem. The data quality has shown remarkable improvement as compared to the conventional radiosonde which will be replaced by the new system. The data of the test ascents were analysed and compared with the first guess data of NCMRWF as shown in Figure - 7. The data was also compared with the Vaisala and Modem radiosonde and have shown good agreement as indicated in Figure - 8.

Figure - 7(a)

Figure – 7(b)

Figure – 8(a)

Figure – 8(b)

Development of the MEMS based sensors for radiosondes is expected to be completed in2010-2011 and will be manufactured in India. An MMIC based Transmitter for radiosonde operating at 1680 Mhz has also been developed with a stability of 1 ppm leading to efficient band width utilisation of radio spectrum.

Doppler Radar

Indigenously fabricated Doppler weather radar has been installed at Mumbai. The S-Band radar is meant for cyclone monitoring and is the first of the two Doppler radars built by M/S Bharat Electronics, India for IMD. The second radar is to be installed at Bhuj.

Wind Profiler

One wind profiler is installed and being used for experimental purposes at Pune. This is built indigenously by SAMEER, an R&D Laboratory under the Governmentof India. The profiler is having a peak power of 16 KW and is having radio acoustic sounding capability for acquiring the virtual temperatures to an average height of 3 km. The profiler is being used experimentally as this was the first prototype. IMD is planning to install few more profilers across the country within two years time.

MODERNISATION OF SERVICES

In addition to the upgradation of the observational facilities other infrastructure of the department is also undergoing extensive upgradation of capabilities by installation of advanced systems.

(a)Up-gradation of Forecasting system:

The forecasting facility is being replaced by hybrid systems in which synoptic method is overlaid on numerical models supported by modern graphical and GIS applications. This is to produce(1) high quality analyses (2) Ensemble of forecasts from numerical models at different scales - global, regional and mesoscale (3) nowcasting with radar mosaics for severe thunderstorms and tornadoes (4) Prediction of intensity and track of tropical cyclone and storm surge (5) Aviation forecasts (6) Forecast and warning for shipping (7) High quality Agro-met Advisory Services (8) High quality extension of the forecast up to district levels.

Various components of the forecasting system have been provided by MFI under the MOU with IMD.

METEOFACTORY

The system is a set of interfaces and automatic processes that provide simple way to:

  1. Design product
  2. Generate product
  3. Disseminate product

Technically, MeteoFactory is divided into three main modules:

  1. Weather data integration
  2. Integrated production system
  3. Dissemination system

Basically MeteoFactory ingests meteorological raw data and provides a convenient GUI to forecasters to enter their expertise in routine orsevere weather situations. Itprocesses these data to produce customised products and services.METEOFACTORY also includes an Early Warning Solution (EWS) for the generation and the dissemination of meteorological alerts and awareness maps.

CLISYS

Main CLISYS system is installed at national data center in Pune. Mirror CLISYS system is installed in New Delhiasdisaster recovery centre.

The CLISYS system shall enable:

  1. Collection and storage of climate data
  2. Safeguard of the climate data
  3. Quality Control of the climate data
  4. User-friendly retrieval of climate data
  5. Creation of custom-tailored and adapted climate products
  6. Interfacing of Climate data Management into to overall NMS Information System

SYNERGIE

SYNERGIE provides a unique visualization interface for any kind of meteorological data through client/server architecture, catering to the operational needs of forecasters.

SYNERGIE is installed at New Delhi and Pune in addition it is also installed at regional meteorological centers and few meteorological centers.

CIPS(Central Information and processing system)

It is installed at Regional Telecom Hub, New Delhi.CIPS is a comprehensive Meteorological Information System. It provides data integration with quality control, data browser, operational & development tasks scheduling and long term data storage with data policy management.

The CIPS includes Long-term Archive Sub-System, Databases, Operational tasks & Integration servers, Development and Spare servers, Scheduler and queuing management servers, Telecom servers, Backup management servers and Tape library backup sub-system.

HPCS (High Power Computing System)

IMD has developed the capability to run numerical weather prediction models in super computers and has recently upgraded its capabilities to run global as well as local models. The HPCS at IMD HQ receives the entire data including manual and automatic devices from across the globe, processes it and generates global and regional forecasts.HPCS has the computing peak power of 14.4 Tera Flops along with 300 TeraBytes of storage. Linkages of HPCS with other divisions is indicated in Figure – 9.

Figure – 9

At the incoming end the HPCS is connected to the central message switching computer called “TRANSMET”.The products are connected to the operational forecasting system of IMD called “SYNERGIE”. It directly flows through the manual value addition stages to product generation platforms which create the dissemination products.HPCS server feeds regional servers through automated ftp via VPN circuits. Data and products are exchanged with other users like Indian Air Force, Indian Navy and others.

Implementation of Global Forecast System (GFS)

A new Global Forecast System (GFS) at T382L64 resolution has been implemented at Northern Hemisphere Analysis Center of IMD on High Power Computing Systems (HPCS).The new GFS is running in experimental real-time mode since 15th January 2010. This new higher resolution global forecast model and the corresponding assimilation system are adopted from NCEP, USA. The GFS at IMD Delhi involves 4 steps as given below:

Step 1 - Data Decoding and Quality Control: First step of the forecast system is data decoding. It runs 48 times in a day on half-hourly basis, as soon as GTS data files are updated at regional telecom hub (RTH) of global telecom system (GTS), at IMD, New Delhi.

Steps 2 – Preprocessing of data (PREPBUFR) : Runs 4 times a day at 0000, 0600, 1200 & 1800 UTC.

Step 3 - Global Data Assimilation (GDAS) cycle :

The Global Data Assimilation cycle runs 4 times a day (00, 06, 12 and 18 UTC). The assimilation system is a global 3-dimensional variational technique, based on NCEP’s Grid Point Statistical Interpolation (GSI) scheme, which is the next generation of Spectral Statistical Interpolation (SSI).

Step 4 – Forecast Integration for 7 days

The analysis and forecast for 7 days is performed using the HPCS installed in IMD Delhi. One GDAS cycle and seven day forecast (168 hour) run takes about 30 minutes.

Products available on Web site and ftp server for public

  • Analysis (MSLP & Winds at 925,850,700,500,300,200,100 hPa )
  • Forecast for 7 days (MSLP, & Winds at 925,850,700,500,300,200, 100 hPa and Rainfall)

(b)Up-gradation of Telecommunication system