C hina F rance O ceanography S A T elliteellite The CFOSAT
project: a cooperation to assess wave directional spectra and
surface winds P.Castillan (1), N. Corcoral (1), C. Tison (1), T.
Amiot (1), E. Thouvenot (1), D. Hauser (2) (1) CNES, Altimetry and
Radar department, France (2) OVSQ, CNRS, LATMOS-IPSL, France
[email protected]
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2 Summary What is the CFOSAT mission? Mission objectives
Description of CFOSAT Focus on the SWIM instrument
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3 The CFOSAT mission CFOSAT: an innovative China/France mission
for oceanography Joint measurements of oceanic wind and waves SWIM:
a wave scatterometer (new instrument) SCAT: a wind scatterometer
(fan beam concept) SWIM, new spaceborne instrument with technology
innovations (antenna, on-board digital processing) SCAT, new
concept of wind scatterometer Access to 2D wave spectrum with high
angular resolution and with global scale Joint measurements of
winds and waves This mission is a world premire SWIM SCAT
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4 The CFOSAT mission CFOSAT is: a scientific mission for public
services (Meteorology agencies, research centers, marine agencies,
etc.) a demonstration and pre-operational mission (for Mto France,
EUMETSAT, CEPMMT, etc.) In situ observations Spatial observations
Models Forecast CFOSAT adds: a new component to spatial
oceanography systems assimilation of CFOSAT data in meteorological
models possible integration of CFOSAT wave measures in
GMES/MyOcean, GlobWave.
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5 Key dates 2006 Signature of the Memorandum Of Understanding
CFOSAT 2007- 2008 Phase A CFOSAT Feasibility demonstration
2009-2010 Phase B CFOSAT Preliminary design 2011-2014 Phases C/D
CFOSAT Detailed design Manufacturing of flight model and
qualification models 2015 Operational system in orbit Launch from
China (end of 2014)
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6 Satellite control A China/France cooperation Platform
CNSA/DFH SCAT CNSA/CAS (CSSAR) SWIM CNES Contract : Thales Alenia
Space Stations CNSA Chinese mission center CHOGS CNSA/NSOAS
Operations CNSA Operations / Mission Satellite X-band TM CNSA/CNES
Contract : Thales Alenia Space X-band stations CNSA/NSOAS Launch /
campaign Polar X-band stations CNES Contract : SSC French mission
center FROGS CNES/IFREMER Control center CNSA Network CNSA CFOSAT
system science & data Principal Investigators D.Hauser
CNRS/LATMOS Liu Jianqiang - NSOAS
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7 Scientific objectives Global observation of ocean wind and
waves with high temporal coverage Why? To improve wind and wave
forecast and sea-state monitoring To improve the knowledge and the
modeling of sea-surface processes To get a simultaneous wind and
wave measures for coupling effects characterization Waves
generation by local winds Free propagation (swell) Bathymetry
impact Coastal wave breaking Secondary objectives (for SWIM) Land
surface monitoring (soil moisture and soil roughness) Polar ice
sheet characteristics
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8 CFOSAT goals Sea state conditions have great impact on:
Commercial activities: marine transport and offshore activity (oil
platform) Pollution transport Security at sea and in coastal areas
Biology and sediment transport Sea-ice formation/destruction Gas
exchange (CO2), stress over the ocean, heat fluxes Sea color
(Albedo) Wind and waves measures are mandatory for weather forecast
and climate survey.
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9 Scientific requirements Mission Minimum duration of 3 years
Global coverage over the oceans (polar orbit) Data available in
near-real time SWIM Directional wave spectra from incidences 6 to 8
To be measured in the wavelength range 70m-500m With a 10% accuracy
on wavelength, 15 accuracy on wave propagation direction With a 15%
accuracy on spectral level around the peak of the spectrum
Significant wave height and wind speed from nadir 10% on SWH (or 50
cm whichever is better) rms
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10 Payloads SWIM Surface Waves Investigation and Monitoring
Real aperture radar in Ku-band 6 incidence angles: 0, 2, 4, 6, 8 et
10 Antenna diameter: 90 cm (~2 aperture) Polarization VV Rotation
speed: 5.7 rpm Power: 120 W Useful bandwidth: 320MHz Pulse
duration: 50 s PRF: 2 - 7 kHz Two scientific payloads SWIM: Surface
Waves Investigation and Monitoring SCAT: wind SCATterometer
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11 Payloads SCAT Wind SCATterometer Real aperture radar in
Ku-band Fan beam concept Incidence angles (on ground): 20-65
Antenna size: 1.2mx0.4m Alternate polarization: HH-VV Rotation
speed: 3.2 rpm Power: 120 W Useful bandwidth: 0.5 MHz Two
scientific payloads SWIM: Surface Waves Investigation and
Monitoring SCAT: wind SCATterometer CSSAR/CAS
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12 Satellite Mass and dimensions Mass ~600 kg Primary structure
~1.5mx1.5mx1.5m Orbit Sun synchronous Local time at descending node
AM 7:00 Altitude at the equator 519 km Cycle duration 13 days
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13 CFOSAT Movie
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14 Ground system IWWOC Waves & Wind Mission Center Brest
CWWIC Instruments Mission Center Toulouse Control center S-band
network Xian Sanya Chinese Mission Center Beijing Mudanjiang
Beijing Kiruna Inuvik Users Worldwide