Post on 31-May-2020
N. Viltard et al, MT Overview, Hamburg, October 2010
The Megha-Tropiques Mission
Nicolas Viltard, Rémy Rocaand the French MT science team
May 8,, 2010 0600Z courtesy www.satmos.meteo.fr
Mission and Algorithms Status
N. Viltard et al, MT Overview, Hamburg, October 2010
Overview
The Megha-Tropiques mission
Indian-French mission by
The Indian Space Research Organisation (ISRO) and the
Centre National d’Etudes Spatiales (CNES)
Dedicated to the
Water and energy cycle in the Tropics➔ 865 km Altitude
➔ Low inclination on the equator (20°)
➔ Microwave imager, microwave sounder, broadband imager
High repetitivity of the measurements
Launch foreseen in early 2011
WEB site http://megha-tropiques.ipsl.polytechnique.fr
N. Viltard et al, MT Overview, Hamburg, October 2010
The Megha-Tropiques missionPayload Courtesy: N. Karouche, CNES
•MADRAS : microwave imager for precipitation : channels at 18, 23, 37, 89 and 157 GHz, H and V polarisations. (conical swath, <10 km to 40 km)
Courtesy: N. Karouche, CNES
N. Viltard et al, MT Overview, Hamburg, October 2010
Orbit characteristics
1 orbit
Half day
Average number of overpasses per day
Latitude
5 63 4
MADRAS sampling over 20°S-20°nMin 3 per day Max 5 per day
The Megha-Tropiques mission
N. Viltard et al, MT Overview, Hamburg, October 2010
Rain-related Day 1 products
Level 1 (Brigthness temperature) typically within 3 hours due to recent enhancement of the reception stations set up.
Access: dedicated agreement with both CNES & ISRO.
None of the products are currently envisioned in NRT L2 typically within the day of acquisition L3/L4 typically within the month, season of acquisition
L2 Instantaneous scale product from MADRAS and all other microwave imaging platforms (BRAIN algorithm)
Sfc Rain Profile of Rain, graupel, snow, (ice & liquid cloud) content over 28 levels Convective rain fraction
L3/4 Accumulated Surface rain from combined Geo IR + L2 : 1° 1 Day “GPCP like” approach (Main differences in the adjustment steps) Homogeneous over the tropical belt
L3/4 MCS rain life cycle composite from combined Geo IR + L2 Cloud tracking + Merging + compositing
March 2010: French/Indian AO => International science team
N. Viltard et al, MT Overview, Hamburg, October 2010
The Megha-Tropiques Products BRAIN: instantaneous rain « L2 »
090204-0922 UTC 090204-0945 UTC 090204-1755 UTC 090205-0234 UTC
090205-1006 UTC 090206-0221 UTC 090206-0930 UTC 090206-1755 UTC
Good coherence TMI-AMSRE, problems with SSM/I => spatial resolutionEvolution of Gael 2009
AMSRE
AMSRE TMI TMI
TMITMI SSMI
SSMI
N. Viltard et al, MT Overview, Hamburg, October 2010
The Megha-Tropiques Products
Kirstetter et al, 2010
Monsoon 2006 over Benin 1°x1° domain
Old retrieval database weights
BRAINTMI
vs. raingauges distribution comparison
New retrieval database weights
N. Viltard et al, MT Overview, Hamburg, October 2010
The Megha-Tropiques products
Accumulated surface rainfall 1°x 1 day and associated error estimation;
TAPEER Algorithm fed from L2 BRAIN and GEO(Tropical Amount of Precipitation with Estimation of ERrors)
GSMAPTMPA TAPEER-BRAIN
Niamey AMMA 2006, filtered 3-5 days
Roca et al., 2010
Ground estimate
Satellite estim
ate
Agregated scale «L3/4»
N. Viltard et al, MT Overview, Hamburg, October 2010
MT cal-val activities: phase I
NIAMEY August 2010
MIT Radar
X-Pol radar
RASTA 95GHz Radar
In-situ Microphysics
Algorithm validation
N. Viltard et al, MT Overview, Hamburg, October 2010
MT cal-val activities: phase I
NIAMEY
MIT Radar: surveillance and aircraft guiding from ground
X-Pol radar
RASTA 95GHz Radar
N. Viltard et al, MT Overview, Hamburg, October 2010
MT cal-val activities: phase I
NIAMEY
MIT Radar
X-Pol radar
RASTA 95GHz Radar
In-situ Microphysics
X-Port dual pol X-band Doppler: climatology of particlesClassification per system typesOperated Monsoon 2010-2012
N. Viltard et al, MT Overview, Hamburg, October 2010
MT cal-val activities: phase I
NIAMEY
MIT Radar
X-Pol radar
RASTA 95GHz Radar
In-situ Microphysics
RASTA 95GHz radar (5 beams)
DopplerOn French Falcon 20
Characterization of M(D)
N. Viltard et al, MT Overview, Hamburg, October 2010
MT cal-val activities: phase I
NIAMEY
MIT Radar
X-Pol radar
RASTA 95GHz Radar
In situ microphysicsOn French F20
PIP, CIP, FSSP...
M(D), N(D) etc...
N. Viltard et al, MT Overview, Hamburg, October 2010
MT cal-val activities: phase I
Algorithm validationconsequences...
N. Viltard et al, MT Overview, Hamburg, October 2010
The Megha-Tropiques mission
Summary
• Due to launch early 2011• Schedule :
– T0 -> T0+3 months: commissioning phase– T0+3 -> T0+9 months: cal/val period, reserved access to
PIs and CO-Is – T0+9 months: start of nominal functionning (open access
to L1 and start of NRT stream for L1 to specific partners)
• Dedicated Data policy for GPM under signature• Algorithm validation campaign w/ Dynamo ?• Product validation campaign Monsoon 11 & 12
N. Viltard et al, MT Overview, Hamburg, October 2010
Thank you !
The Megha-Tropiques mission
http://meghatropiques.ipsl.polytechnique.fr
N. Viltard et al, MT Overview, Hamburg, October 2010
SAPHIR : microwave sounder for water vapour sounding : 6 channels in the WV absoption band at 183.31 GHz. (cross track, 10 km)
•ScaRaB : broad band instrument for inferring longwave and shortwage outgoing fluxes at the top of the atmosphere (cross track scanning, 40 km resolution at nadir)
GPS RO: water vapor profile …
GEOSTATIONARY DATA•Cloud mask for the MW algo•Quicklook for interpreting MT data•Basic inputs for MCS tracking algorithm •Basic inputs for Level 4 rainfall (radiation) products
Payload (2/2)The Megha-Tropiques mission
Source: N. Karouche, CNES