National Centre For Medium Range Weather Forecasting (NCMRWF)

Mission

• To provide accurate, quantitative location specific medium range weather forecasts and agro-meteorological advisories to farmers
• Numerical Weather Prediction (NWP) guidance to partners/user agencies
• Customized forecast products for other applications.

Vision

• To become, in the next decade, first preferred choice for NWP guidance over Indian Monsoon Region and global Tropics for all Weather and its applications related requirements on medium/extended/seasonal ranges
• To develop an "Earth Weather/Climate Modelling and Assimilation System" especially for Monsoon System, consisting of global & regional atmosphere-land-ocean modules
• To develop newer applications and reach out to society at large to maximize benefits from our products
• This shall be achieved by constantly striving to improve accuracy, consistency and range of our global and regional NWP products through emphasis on focused R&D, regular technology upgradation, human resource development, networking and partnership with major global weather and climate prediction/diagnostic centres of the world, research laboratories and academia both within the country and abroad

Global Modelling

Medium range weather forecasting (spanning from 3 to 10 days) involves the use of global numerical weather prediction (NWP) models and their integration over time starting with a given initial state.

NCMRWF runs two global spectral models (T-80) and (T-170) which produce daily global forecasts. The horizontal resolution of these models, are 150 km and 75 km respectively.

The atmospheric system that we attempt to predict is chaotic. The skill of a deterministic forecast is limited by the uncertainty in the initial conditions and the model errors. An ensemble prediction system, which involves the generation of multiple forecasts as a function of the uncertainty in the initial conditions, has been developed and experimental runs are underway.

R & D efforts are focused on the reduction of model errors through better representation of physical processes.

Mesoscale Modelling

Mesoscale models are essential for accurate prediction of high impact weather, such as severe thunder storms, heavy rainfall events, mountain weather forecasting, cloudbursts, cyclone, etc.

At NCMRWF mesoscale models (MM5 & Eta) are run up to 72 hours on real-time for high impact weather prediction using initial and boundary conditions from the global forecast model.

MM5 model is run on triple nested domains at 90, 30 and 10 km resolutions. The 10 km nests are placed over the central Himalayas and West Bengal region.

ETA model is run at 48 km and 22 km resolutions covering India and neighbourhood. Eta model's ocean surface winds are used to run coastal & regional ocean wave models.

Research is being conducted on 3D-VAR mesoscale data assimilation for inclusion of high-resolution observations from satellite, radars, mesonet and many other conventional and non-conventional data sources in the mesoscale model. Data Assimilation

Numerical weather prediction model needs an initial estimate of three-dimensional atmospheric condition as a starting point to make predictions. The process of optimally combining observed data with model-generated data to construct the best possible estimate of an initial state is known as data assimilation.

Global Data Assimilation System

• Six-hourly intermittent scheme
  
• Uses global observations from different observing systems viz., surface observatories (SYNOP ~10,000), ships (~1000), buoys (~2000), aircrafts (~1500), RS/RW (~800), pilot balloons (~250) and satellites (~30,000)
  
• Comprehensive quality control off observed data
  
• 3-Dimensional variational analysis (Spectral statistical Interpolation) at T80/L18 and T170/L28 resolution

Ongoing R&D

• Higher resolution (10 km) meso-scale data assimilation
  
• Assimilation of non-conventional data
  • Satellite radiance
  • Radar radial velocity
  • GPS refractivity

Challenges

• Land-Surface assimilation
  
• Ozone & cloud assimilation
  
• 4-D Variational Assimilation
  
• Ocean data assimilation

• Reliable extended range weather forecasts are very useful for planning & management of water, power, food, health and economy sectors of any country.
  
• Currently at NCMRWF the dynamical approach is used for extended range (monthly) prediction based on simulations from the global (T80/L18) atmospheric model.
  
• Analog and Persistent SSTs prepared by SAC/ISRO are used in these simulations. Probability of occurrence of excess, normal, or deficient rainfall (anomalies computed based on model climate) for six homogenous regions of the country is computed.
  
• Year 2002 was the worst drought in last 30 years. Failure of 2002 & 2004 Monsoon is the cause of renewed interest to develop an accurate 'Dynamical Seasonal Forecast System' at NCMRWF.
  
• Indian Monsoon is a fully 'Atmosphere-Ocean-Land' coupled system. The ENSO, MJO signals, the realistic amplitude and phase of MJO and the strength of coupling are best captured in a coupled model.
  
• At NCMRWF a more accurate coupled system is being developed to understand and predict the monsoon environment a season in advance. Experiments are being conducted to reduce model systematic errors and model uncertainties. This will also help in diagnosing the cause for poor simulation of MJO. Multi-model ensembles will be finally used to allow for chaotic nature of the climate system and to enable detection of the signal above the noise.
  

Ocean State Forecasts

Accurate ocean state forecasts are in great demand for ship routing, fisheries, tourism, oil exploration and port & naval operations.

Ocean surface parameters (wind and fluxes) from global & mesoscale models of NCMRWF drives most of the wave and ocean models in the country in both real-time & research mode.

NCMRWF plays a pivotal role in the country's Ocean State Forecasting efforts. Atmospheric forcing parameters from NCMRWF are used in real-time at INCOIS Hyderabad & NODPAC, Kochi for operational purposes and for research at various national institutes (namely, SAC, IIT Delhi/Chennai, NPOL, NIO and IITM)

Inter-comparisons have shown that ocean surface winds of the analysis-forecast system at NCMRWF are of high quality.

Indian Navy used ocean surface winds from NCMRWF for the successful navigation of the first circumnavigation voyage of their sailing ship (INS Tarangini) during January 2003 - May2004.

NCMRWF also runs daily a global ocean wave model (WAVEWATCH-III) at 1º resolution to predict significant wave heights, peak wave direction, wave period etc Collaborative Research

NCMRWF has been actively participating in a number of international and national collaborative research programmes.

India Meteorological Department (IMD), Indian Council for Agricultural Research (ICAR), and a number of international research centres such as Center for Ocean-Land-Atmosphere Studies (COLA), National Centers for Environmental Prediction (NCEP, formerly National Meteorological Center), and European Centre for Medium Range Weather Forecasts (ECMWF), have been providing all possible cooperation to NCMRWF towards achieving its objectives since its establishment in 1988.

Collaborative research projects are either ongoing or are being developed with number of leading Centres such as NCEP, National Center for Atmospheric Research (NCAR), Florida State University (FSU), University of Maryland (UM), North Carolina State University (NCSU), University of Washington (UW), International Research Institute for Climate Prediction (IRI), Meteorological Office (UKMO), Laboratoire de Meteorologie Dynamique (LMD), Max Plank Institute of Chemistry (MPIC), etc.. NCMRWF interacts very actively with all the meteorological centres/services of neighbouring countries.

NCMRWF has enjoyed special ties with the Agriculture Universities in the country where many of its Agro Advisory Units (AAUs) have been established. It is an active partner in many multi-institutional research programmes at national level involving many departments/research centres. These include IMD, Indian Institute of Science (IISc.), Indian Institute of Tropical Meteorology (IITM), Space Application Centre (SAC), Indian Space Research Organization (ISRO), Indian Institute of Technology, Delhi (IITD), Indian National Centre for Ocean Information Service (INCOIS), Snow and Avalanche Study Establishment (SASE), Centre for Mathematical Modeling and Computer Simulations (CMMACS), Cochin University for Science & Technology (CUSAT), Andhra University (AU) etc.

Applications

Crop Models & Decision Making

NCMRWF has validated Dynamic Crop Simulation Models for different crops at Agro-Advisory Units (located at State Agricultural Universities and Indian Council of Agricultural Research institutions) for medium range weather forecast based farm decision making in an objective manner.

Weather based farm level decision making using crop models Strategic

• Crop and cultivar selection- short/long duration and early/late maturing
  
• Sowing window selection
  
• Land utilization

Tactical

• Optimum sowing time
  
• Irrigation management
  
• Fertilizer application
  
• Hoeing and weeding operation
  
• Pesticide/insecticide spray
  
• Harvest operation
  
• Post harvest operation

Vision

• Development of crop model based Application Tools and Experts System for use in farm level agro-advisory preparation
  
• Use of remote sensing products to address the variability within the agro-climatic zones
  
• Precision farming using GIS

Biweekly Weather Forecast Bulletin valid for 4 Days disseminated to AAS units

• 24 Hr Precipitation (mm)
  
• Average Cloudiness (Okta)
  
• Av. Wind Speed (kmph) at 10 Ft level.
  
• Predominant Wind Direction at 10 Ft level.
  
• Maximum Temp. Trend ( C) at 4.5 Ft level. Minimum Temp. Trend ( C) at 4.5 Ft level.
  
• Weekly Cumulative Rainfall (mm)

Daily Weather Forecast Bulletin kept on NCMRWF's home page contains

• Prevailing weather situation
  
• Forecast for the subsequent 4 days
  
• Forecast for extreme weather events like: frost, cold/heat wave, heavy rainfall/ snowfall, dry spell, strong winds, hail, cyclone

Bi-weekly Agro Advisory Bulletin Contains Information on

• Crop-wise farm management information tailored to weather sensitive agricultural practices
  
• Pest & disease information and prevention
  
• Livestock management information for housing, health, nutrition etc.

All-India agromet advisory Bulletin on crops

• compiled at the centre using inputs from AAS units
  
• Inputs taken from the India Meteorological Department
  
• Preparation of all India agro-advisories at NCMRWF
  
• Telecast through the Kisan Channel on every Tuesday/Friday
  
• Presented in the Crop Weather watch Group of Ministry of Agriculture every Monday

Computing resource of NCMRWF that includes high-end Cray-SV1 vector system and indigenous parallel system, PARAM Padma is the best high-end computing facility in the country. Cray SV1 is used for generating operational global and regional NWP products, research, for human resource development in the field, and for data processing, archival and supply to users. PARAM Padma is used exclusively for R & D activities.

The centre has its own web page (www.ncmrwf.gov.in) on which graphical forecast products are kept and updated regularly. The forecast data from the various numerical models of NCMWRF are made available to users through the anonymous ftp server (ftp.ncmrwf.gov.in). NCMRWF is in the process of starting Web based Data Service for meteorological data and products.

NCMRWF has tried to keep pace with the latest technology trends by upgrading its infrastructure in a phased manner.

Training

NCMRWF is emerging as a hub for training on NWP techniques and their applications.

NCMRWF provides training on NWP techniques and the use of NWP products to the personnel from various user agencies and to scientists from other developing countries.

NCMRWF also provides training regularly to the Agricultural Scientists working in Agrometeorological Advisory Service (AAS) on data monitoring and management, weather forecasting and crop simulation models.

Most of our scientists serve as resource people and guides, for research students to help develop talent in the field.

NCMRWF has helped in setting up global/mesoscale models in various institutes within the country and at few places outside the country to enable them to cater to their specific requirements.

For further information on NCMRWF, please visit: www.ncmrwf.gov.in

Contact

For more information please contact:

The Head, NCMRWF
Department of Science & Technology
A-50, Institutional Area, Phase-II
Sector-62, Noida,
UP - 201 307
Tel: 91-120-2403900-07
Fax: 91-120-2400062
Email: akbohra at ncmrwf dot gov dot in