Utilisation of MTSatellite observations at NCMRWF : Plan

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• Utilisation of MT-Satellite observations at
  NCMRWF Plan prospects
• K. Bohra, M. Das Gupta, John P. Geogre, R. Ashrit
  A.K. Mitra
• National Centre for Medium Range Weather
  Forecasting
• NOIDA, India

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• Objectives of NCMRWF
• Development of operational Global and regional
  scale NWP models for forecasting weather in
  medium range(3-10 days) time scale taking full
  advantage of existing and concurrent
  developments in this field
• To inform and guide the farmers in advance to
  undertake various farming activities based on
  the expected weather
• Research on various aspects of NWP
• A near real time numerical weather prediction
  (NWP) suite is being run operationally at NCMRWF
  since 1st June 1994 to issue medium range
  weather forecasts over Indian subcontinent

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NWP Models at NCMRWF Global Models T-80 150
km x 150km resolution T-170 75kmx75km
resolution Meso-scale Models MM5 Nested 90,
30, 10 km resolution Eta 48km
resolution RSM 50km Ocean Wave
Model WAVEWATCH-III at 1 deg.for global ocean
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Forecast to different Sectors
Agriculture
Power
Water Resources
Armed Forces
NCMRWF Forecast
Adventure
Tourism
Shipping Fisheries
Space
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• To make a accurate forecast it is important to
  know the current weather
• Global observations are continuously downloaded
  through GTS and ftp access and fed into the
  assimilation system
• about 106 observations are processed in each
  assimilation cycle

Global Satellite Obsn.
Global Aircraft Obsn.
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Aircraft
RS/RW

• Global Data assimilation System (GDAS)
  operational at NCMWRF
• 6-hrly intermittent
• 3D-VAR analysis (SSI)
• conventional and satellite obsn.

PilotBalloon
Surfaceobservations
GTS DATA
Ships Buoys
Satellite data
RTHNEW DELHI
FTP Satellite Data MSMR, SSMI etc.
DATA RECEPTION DECODING at NCMRWF(1/2 hrly)
DATA PROCESSING AND QUALITY CONTROL

• Satellite data assimilated at NCMRWF
• Classical CMVs from GOES,
  METEOSAT,GMS and Kalpana
• High resolution winds from METEOSAT-5(63ºE)
• ATOVS (120km) temperature and total
  precipitable water(TPW) (500km TOVS)
• SSM/I, (MSMR) wind speed
• QSCAT, (ERS-2) winds

PREVIOUS (6 HOURS)ANALYSIS
Repeated four times a day 00,06,12 18 UTC
PREVIOUS (6HR.)ANALYSIS
DATA PROCESSING QUALITY CONTROL
SSI ANALYSIS
SURFACEBOUNDARYCONDITIONS
ANALYSIS
SURFACE BOUNDARYCONDITIONS
T80 GLOBAL SPECTRAL FORECAST MODEL
MEDIUM RANGE WEATHER FORECAST BASED ON 00 UTC
ANALYSIS
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• Satellite data utilisation in data assimilation
  forecast system
• Some of the recent studies carried out at
  NCMRWF
• Impact of satellite derived temperature profile
  data on medium range forecasts (TOVS
  NOAA-12/14 coarse resolution - 500 km)  Global
  Ocean Atmosphere Systems , 1998
• TOVS temperature profile data at its full
  resolution ( With IMD / HRPT -85 Km )
  Meteorology Atmos. Physics, 1999
• Improve the quality of INSAT derived CMVs
  Height re- assignment by employing guess fields
  from global forecast model ( With IMD )
  Meteorology Atmos. Physics, 2002
• The divergent part of the wind was improved by
  using INSAT OLR information as input in analysis
  system( with IITM ) Meteorology Atmospheric
  Physics, 1997
• Derive synthetic moisture profiles from INSAT
  IR data JMA and BMRC type technique Int. J
  of Remote Sensing, 2002 / Atmosfera, 2001
  
  

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• Assimilation of MSMR data in NCMRWF global data
  assimilation system (with IIT-D),
  Meteorology and Atmospheric Physics, 2002
• Impact of ATOVS temperature and moisture
  profiles, Mausam, 2003
• Impact of ERS-2 scatterometer winds Mausam,
  2002
• Impact of High Density Atmospheric Motion
  Vectors,
• 6th International Winds Workshop, 2002
• Analyses of Orissa Super Cyclone using TRMM
  (TMI), DMSP (SSM/I) and OceanSat-I (MSMR) Derived
  Data, The Global Atmosphere and Ocean System,
  2003
• Observed daily large-scale rainfall patterns
  during BOBMEX-99, Earth Planetary Science, 2003
• Daily Rainfall for Indian Monsoon Region from
  Merged satellite and Rain-Guage Values
  Large-Scale Analysis from Real Time data, Journal
  of Hydrometeorology, 2003

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Impact studies with SSM/I and MSMR wind speed
TPW
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Impact of SSM/I wind speed and TPW
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Comparison of SSM/I and MSMR wind speed with Buoy
obsn.
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Experiments with TRMM/TMI Data Orissa Super
Cyclone October 1999 TPWC , Wind Speed
from- TMI / TRMM SSM/I MSMR
METEOSAT - 5
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Simulated track of super-cyclone based on 00UTC
24 Oct 2005
20 31 Oct 1999 / TPWC Wind Exp1 TRMM 25
km Exp2 TRMM averaged to 75 km Exp3 SSM/I
averaged to 75 km EXP4 MSMR 75 km Best
simulated track is from the analyses with TRMM
(25 km) and METEOSAT-5 (not shown) However,
forecast quality was still poor even in T170
version and with 25 km TRMM data Vertical
structure is important ATOVS type data might
improve
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Experiments with ATOVS (NOAA 15 16) temperate
and moisture (global model)
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Temperature at 850 hPa NOAA 15 16 00UTC
29 Sept 2001
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Specific Humidity at 850 hPa NOAA 15 16
00UTC 29 Sept 2001
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TPWC (mm) NOAA 1516 00UTC 290901
TPWC (mm) SSM/I 00UTC 290901
SSM/I obsn. more moist over Tropics
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(mm)
as expected analyses with SSM/I are more moist
than analyses with ATOVS
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Total rainfall Sept. 2001
with SSM/I
OBS
D1-FCST
with ATOVS
SSM/I - more rainfall over Ocean ATOVS -
rainfall reduced over Ocean more over Indian
land
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Experiments with ATOVS (NOAA 15 16) temperate
and moisture (Mesoscale model MM5 3DVAR)
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without ATOVS
with ATOVS
Analyses of a monsoon low with without ATOVS
(temp. moisture) 850 hPa height wind
00UTC 27th, 28th 29th July 2004
In analyses with ATOVS, low is better organized,
with centre of circulation coinciding with
contour low
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without ATOVS
with ATOVS
24hr., 48hr. 72 hr. prediction based on 00UTC
26th July 2004 with without ATOVS (temp.
moisture) 850 hPa height wind
system is predicted more intense, in with ATOVS
run
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Validation of radiative fluxes
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Validation of Net Radiatve Fluxes using LASPEX
data set over Anand
Monsoon
Summer
Post-Monsoon
Winter
T80 simulation of net radiative fluxes matches
well with observation in clear sky condition
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Recent Heavy Rainfall Episode over West Coast of
India
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Unprecedented Heavy Rainfall(95cm) over Mumbai
on 26th July 2005, very localized event over a
region 20-30kms

• NCMRWFs operational models could not predict
  such high rainfall with initial condition from
  its 3D-VAR assimilation system (without radiance)
• Same event is better simulated with initial
  condition generated by 4DVAR (with radinace)
  assimliatiion (obtained from UKMO)

With NCMRWF analysis
With UKMO analysis
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• Studies related with different physical
  parameterization schemes conducted at NCMRWF
• Convection KUO/RAS/SAS
• PBL Local / Non-Local closure
• Radiation GFDL / Harshavardhan

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Satellite rain gauge merged rainfall analysis
(real time product for model validation)
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Total rainfall Sept 2001
Satellite rain gauge merged product (NCMRWF)
CMAP (XIE-ARKIN) Rainfall
heavy rainfall over peninsular India and over
Nepal and adjoining NE India is captured better
in NCMRWF product
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Comparison of Analysed rainfall amount
June 2001
(OBS)
Rainfall in cm
Southern part of west coast
East coast north BOB
Central India monsoon trough reg.
Northern part of west coast
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• Future Scenario
• Developments of NWP models (global) trends
• Increased horizontal and vertical resolution
• Horizontal resolution 8-15 km (2015), 3-5 km
  (2025)
• Vertical resolution
• Boundary layer 70m (2015), 40m (2025)
• Free atmosphere 300m (2015), 200m (2025)
• Stratosphere 500m (2015), 200m (2025)
• Global NWP is likely to cover FC24 onwards
• Similar to what meso-scale models are now
• An accurate description of the hydrological
  cycle is vital for short/medium range
  forecasting (NWP models)

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Expected observations from Megha-tropique
satellite

• Megha-tropique satellite is proposed to carry
  three scientific instruments
• Multi-frequency Microwave Scanning Radiometer,
  MADRAS
• rain above the oceans surface winds,
• integrated water vapour content,
• liquid water in clouds,
• convective rain
• Multi-channel Microwave Instrument, SAPHIR
• vertical humidity profile in the atmosphere
• Multi-channel instrument, SCARAB
• earth's radiation budget

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• Possible Use of Megha-Tropiques data at NCMRWF
• Input to the NWP models
• Model validation
• 1. Input to the NCMRWF assimilation- forecast
  system-
• Ocean surface wind, integrated water vapor
  and rain (MADRAS)
• Water vapor profiles in the cloud free
  troposphere (SAPHIR).
• Use of these parameters in assimilation system
  may improve the distribution of the water vapor
  over the tropical oceans in analysis, which may
  ultimately improve the convection and other
  precipitation processes in the model.

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• Cloud liquid water and ice (MADRAS)
• can be used an input to the model, which may
  improve the computation of cloud optical
  properties (input to the radiation scheme) in the
  model and hence the radiation fluxes and
  heating/cooling rates.
• 2. Model validation
• Shortwave and Longwave radiation (ScaRaB)
  measurements are useful for the validation of
  the radiation scheme over the tropical areas. The
  radiative fluxes observation in this mission is a
  valuable data to validate the model generated
  cloud radiative forcing.
• Deep convection areas, cloud liquid water,
  precipitation, cloud top ice, anvil areas and
  humidity profiles (SAPHIR, MADRAS)
  useful for the validation of
  the parameterization of convection and other
  precipitation processes in the model

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Proposed studies using observations from
Megha-Tropiques satellite
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• (1) Data Assimilation
• direct radiance assimilation
• assimilation of surface wind, TPW
• rainfall assimilation (nudging / 4DVAR)
• observing system experiments

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• (2) Convection-Radiation Study
• initiation and life cycle of convective systems
  over the Asian Monsoon Region has to be studied
  using Mesoscale/Cloud Resolving Model (MCRM) and
  data from Megha-Tropiques
• preparation of cloud climatology for Asian
  Monsoon Regime
• ScaRab radiation data will be used for
  comparing and ultimately improving radiation
  budget of numerical models

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• (3) Large scale intra-seasonal monsoon
  variability
• Hadley Walker circulations, Water vapour
  transport
• Feedbacks on radiation
• Madden-Julian oscillations
• Onset, break and variations of monsoons
• Ocean-Atmosphere interactions

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• Local retrieval
• retrieval through RT models using MW SCARAB
• Use NCMRWFs meso-scale NWP outputs
• Improved temp. , mositure and rainfall

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• Rainfall analysis
• calibration of IR rainfall with MW rainfall
• technique for blending of rainfall data from
  Megha-Tropiques, TRMM, SSM/I and other
  geo-stationary satellite to
• generation of grided rainfall dataset at
  different required (synoptic and meso scales)
  resolution

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Thank You