Status of GCOM-C/SGLI
Hiroshi Murakami
Japan Aerospace Exploration Agency(JAXA)
Earth Observation Research Center(EORC),GLI 250m 2003/09/24

1

1. Introduction of GCOM and SGLI
1.1 History and targets of GCOMJAXA and science groups (Global Climate Observation Mission (GCOM) and SGLI application committees)
have discussed about the Second generation Global Imager (SGLI), which is a radiometer of visibleinfrared, middle-resolution, and global and frequent observation, for more than five years.
After the trouble of ADEOS-2, we are setting 2011 as the launch date of the first GCOM-C satellite
which will carry SGLI. The SGLI have to be mature sensor with low risk, long life (consists of series ofthree satellites; total 13 years), and wide applicability. “2011” is perhaps delayed by a difficulty of financial resources
Targets of GCOM (consists of GCOM-W and GCOM-C satellite series) are followings.
Build an long-term observation system which can observe effective physical parameters
continuously (10~15 years) for solving the global climate change and water-cycle mechanism,and establish its usability
Process the satellite data aiming at integrative use into other observation systems, model data,etc., and provide users
Contribute to improvement in the predictive accuracy of a long-term climate change, whichconnects with national policy decision, through the improvement of the process research about aclimate-change mechanism and a numerical climate model with cooperation to the userorganizations.
Contribute to the operational fields, such as prediction of intense weather which brings about
disaster, through data distribution to the operational organizations which perform a weather
forecast, fishery information service, sea route information control, etc.
Develop new products effective in the elucidation of a climate change and a water cycle
mechanism which are difficult to make with the present analysis technology.

2

1. Introduction of GCOM and SGLI
1.2 JAXA’s earth observation scenario
Targets
Disastermonitoring &Resources
management

Globalworming &Water cycle
observation
Water cycle~2002[Optical imager]
MOS-1, ADEOS(87~95) (96~97)[Optical imager &SAR]
JERS-1 (92~98)

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015

ALOS

Missions for disaster monitoring[Precipitation
radar]
PR (97~)[Microwave
radiometer]
MOS-1 (87~95)

Geostationary satellite

GPM/DPR [Precipitation]

TRMM/PRADEOS-II/AMSR

GCOM-W / AMSR
[wind, SST , water vapor]

Aqua/AMSR-E

Globalclimatechange[Optical imaging[Vegetation, aerosol, cloud, SST, ocean color]radiometer]
MOS-1,ADEOS-II/GLI 250m, multi-angle, polarization
ADEOS/OCTS
GCOM-C / SGLI
(87~95) (96~97) [aerosol, cloud, ocean color,[Cloud and Aerosol 3D structure]
SST,
vegetation,
snow][Cloud profiling
EarthCARE
radar]

Greenhousegases[Spectrometer]
ADEOS/ILAS(96~97)

note

Launched

ADEOS-II/ILAS-IIGOSAT [CO2, Methane]
Development

Research

Extension3

1. Introduction of GCOM and SGLI
1.3 Outline of GCOM-W/AMSR2AMSR 2

Targets of GCOM-W are water-energy cycle.
GCOM-W1 will carry AMSR-follow on, AMSR-2.
GCOM-W AMSR-F/O characteristics
Sun-synchronous (ascending local time: 13:30)
Orbit (TBD)
Altitude: 699.6km, Inclination: 98.19deg
Launch Date2010 (HII-A)
Mission Life
5 years (3 satellites; total 13 years)
Scan
Conical scan microwave radiometer
Swath width
1450kmAntenna2.0m offset parabola antenna
Digitalization
12bit
Incident angle Apporox. 55 degree
Polarization
Vertical and Horizontal
Dynamic range 2.7-340K“2010” is perhaps delayed by a difficulty of financial resources
Band
(GHz)
6.925
10.65
18.7
23.8
36.5
89.0

Band
width
(MHz)
350
100
200
400
1000
3000

Polariza
tion
V
and
H

Beam width [deg](Ground resolution[km])
1.8 (35 x 62)
1.2 (24 x 42)
0.65 (14 x 22)
0.75 (15 x 26)
0.35 (7 x 12)
0.15 (3 x 5)

Sampling
interval[km]
10
5• AMSR-2 will continue AMSR-E observations (water vapor, cloud liquid water, precipitation, SST, windspeed, sea ice concentration etc.).
• Above images show evaporation (top), precipitation (middle), and their difference (bottom) in Jun (left)and December (right) 2005 estimated using AMSR-E L3 products.
4

1. Introduction of GCOM and SGLI
Polarization
1.4 Outline of GCOM-C/SGLI

Shortwave (SW) &thermal infrared (T)scanning radiometermuti-angle
radiometer (P)Targets of GCOM-C are carbon cycle and radiationbudget.
SGLI will continue almost of the GLI observations(sea surface temperature, ocean colour, aerosols,
cloud, vegetation, snow/ ice, and so on). The new
SGLI features (250m (VN) and 500m (T) channels
and two polarization/ multi-direction channels(P)) will enable improvement of land and coastal
monitoring and retrieval of land aerosols.
Narrow  and relatively high SNR for ocean products
New features of SGLI from ADEOS-2/GLI
GCOM-C SGLI characteristics
Sun-synchronous (descending local time: 10:30)
Orbit (TBD)
Altitude: 798km, Inclination: 98deg
Launch Date2011 (HII-A)

Mission Life

5 years (3 satellites; total 13 years)

Push-broom electric scan (VN & P)
Wisk-broom mechanical scan (SW & T)
1150km cross track (VN & P)
Scan width
1400km cross track (SW & T)
Digitalization
12bit
Polarization
3 polarization angles for P
Along track+45 deg and -45 deg for P
direction
Nadir for VN, SW and T“2011” is perhaps delayed by a difficulty of financial resources

Scan

Visible & near infrared (VN)
push-broom radiometer

CH
VN1
VN2
VN3
VN4
VN5
VN6
VN7
VN8
VN9
VN10
VN11
P1
P2
SW1
SW2
SW3
SW4
T1
T2

SGLI channels
Lstd
Lmax


VN, P:
VN, P, SW: nm
W/m2/sr/m
T: m
T: Kelvin
380
10
60
210
412
10
75
250
443
10
64
400
490
10
53
120
530
20
41
350
565
20
33
90
670
10
23
62
670
20
25
210
763
8
40
350
865
20
8
30
865
20
30
300
670
20
25
250
865
20
30
300
1050
20
57
248
1380
20
8
103
1640
200
3
50
2210
50
1.9
20
10.8
0.7
300
340
12.0
0.7
300
340

SNR at Lstd

IFOV

VN, P, SW: T: NET

m

250
400
300
400
250
400
400
250
400
400
200
250
250
500
150
57
211(TBD)
0.2
0.2

250
250
250
250
250
250
250
250
1000
250
250
1000
1000
1000
1000
250
1000
500
500

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1. Introduction of GCOM and SGLI
1.5 Features of SGLI ocean observation
250m Ocean colour product simulated using GLI 250m channels(a) GLI 1km Osaka Bay(1 Oct. 2003, CHL by LCI)(b) GLI 250m Osaka Bay(1 Oct. 2003, CHL by LCI)SGLI 250m resolution will enable to detect more fine structure in the
coastal area such as river outflow, regional blooms, and small current.
62. Status of GCOM SGLI program
2.1 Time table
Time

Event

JFY
2005

2005 Sep.
2005 Oct.

Review of GCOM-W/C Breadboard Model (BBM) study
Start BBM design and trial manufacture ~JFY2007
--

JFY
2006

2006 Jun 15
2006 Jun ~Jul.
2006 Sep.~Oct.
2006 Dec. 27
2007 Jan 29~31...

GCOM Symposium (Tokyo)
GCOM-W1 Evaluation in the Space Activity Commission sub-groups
Evaluation by Committee for Scientific and Technological Policy
Design review of the SGLI BBM
AMSR/E GLI workshop

JFY
2007

2007 Spring
...
200X

GCOM/EarthCARE Symposium in Tokyo (TBD)
Pre-evaluation of GCOM-C1 (TBD)•SGLI have to approved by this evaluation to go to the following steps.
•Now we are trying to undergo the evaluation…

JFY
2008~

2008 March

Review of the SGLI BBM

??
...
??
...
JFY2010 (TBD)
JFY2011 (TBD)

Develop Engineering Model (not approved)
Develop Pre-Fright Model (not approved)
GCOM-W1 Launch (TBD)
GCOM-C1 Launch (TBD)“ 2010” and “2011” are perhaps delayed by a difficulty of financial resources7

3. SGLI Ocean Science Plan
3.1 Products and target accuracy
SGLI radiance product (L1B)
Categoryradiance

Product
Radiometric corrected radiance withgeometric information

Type* File unit

1

S

Resolution

250m (land and
Scene, global (day) coast)
1km (offshore)Threshold for data
releaseStandard accuracy*1

Target accuracy*1

TBD

VN/SWIR 5%*2, 1%(relative)
TIR: 0.5K(@300K)

VN/SWIR 3%*2, 0.5%
(relative)

Threshold for data
releaseStandard accuracy*1

Target accuracy*1

50% (<600nm)
0.5W/m2/sr/um(>600nm)
50% (a_865)
15% (10km/month)

30% (<600nm)
0.25W/m2/sr/um(>600nm)30%
10% (10km/month)

SGLI Ocean products
Category

Atmosphericcorrection

In-waterparameters

Product
Normalized Water Leaving RadianceS

Atmospheric Correction Parameters
Photosynthetically Available Radiation

S
S

Euphotic Zone Depth

R

Chlorophyll-a Concentration

S

Suspended Solid concentration
Colored Dissolved Organic Matter

S
S

Inherent Optical Properties

R

Temperature Sea Surface Temperature

Application

Type File Unit

S

Ocean Primary Productivity

R

Phytoplankton Functional TypeR

RedtideR

Multi-sensor Ocean ColorR

Multi-sensor SST

R

scene, global(day/8 day/month)

Resolution

60% (443~565nm)
80% (a_865)
20% (10km/month)scene, global
250m (coast)
N/A
N/A(day/8 day/month) 1km (offshore)
4~9km (global bin)
60~+150% (offshore) 60~+150%
scene, global
60~+150% (offshore) 60~+150%(day/8 day/month)60~+150% (offshore) 60~+150%
scene, global
N/A
N/A(day/8 day/month)
500m (coast)scene, global
1km (offshore)
0.8K
0.8K (daytime)(day/8 day/month)
4~9km (global bin)
500m (coast)scene, global
1km (offshore)
N/A
N/A(day/8 day/month)
4~9km (global bin)
250m (coast)
N/A
N/A
scene, global
1km (offshore)(day/8 day/month)
N/A
4~9km (global bin) N/A
scene, global
250m (coast)
N/A
N/A(day/8 day/month) 1km (offshore)scene, global
500m (coast)
N/A
N/A(day/8 day/month) 1km (offshore)

30%(TBD)35~+50% (offshore),50~+100% (coastal)
50~+100%
50~+100%
TBD
0.6K

TBD
TBD
TBD
TBD
TBD

S: Standard products, R: Research products

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3. SGLI Ocean Science Plan
3.2 SGLI products and channels
 Lstd-

VN, P: nm
T: m

Lmax

SNR

VN, P:
at Lstd
W/m2/sr/m VN, P: T: Kelvin
T: NET

IFOV*3

m

Land

Ocean

Atmosphere

Cryosphere

Ice Sheet Boundary Monitoring
Ice Sheet surface RouGHness
SNow ImPurity
Snow and Ice ALBedo
SNow Grain Size of Top layer
SNow Grain Size of Subsurface layer
SNow Grain Size of shaLlow layer
Snow and Ice Surface Temperature
Snow Covered Area in Forest and Mountain
Snow and Ice Classification
OKhotsk sea-Ice Distribution
Snow and Ice Covered Area
multi sensor Merged Sea Surface Temperature
multi sensor Merged Ocean Color parameters
Red TiDe
PHytoplankton Functional Type
Ocean Net Primary Productivity
Sea Surface Temperature
Inherent Optical Properties
absorption coefficient of Colored Dissolved Organic Matter
Suspended Solid concentration
CHLorophyll-A concentration
Euphotic Zone Depth
Ocean Photosynthetically Available Radiation
Atmospheric Correction Parameters
Normalized Water Leaving Radiance
ShortWave Radiation Flux
LongWave Radiation Flux
AeRosol by Polarization
Land AeRosol over the land by near Ultra violet
AeRosol over the ocean by Visible and near infrared
Water Cloud Geometrical Thickness
Ice Cloud Optical Thickness
Water Cloud Optical Thickness and Particle Effective Radius
Cloud Top Temperature and HeightClassified CLoud Fraction
CLoud FlaG including Cloud Classification and Phase
Land surface ALBedo
Land Cover TypeFire Detection Index
Plant Water Stress trend Index
Land Net Primary Production
Above-Ground BIOmass
Leaf Area Index
Fraction of Absorbed Photosynthetically Active Radiation
Land Surface Temperature
Shadow Index
Vegetation Roughness Index including BSI_P and BSI_V
Vegetation Index including NDVI and EVI
Atmospherically Corrected Land surface Reflectance
Precise Geometrically Corrected Image

CH

VN1
VN2
VN3
VN4
VN5
VN6
VN7
VN8
VN9
VN10
VN11
P1

380
412
443
490
530
565
670
670
763
865
865
670

10 60
10 75
10 64
10 53
20 41
20 33
10 23
20 25
8 40
20 8
20 30
20 25*1

210
250
400
120
350
90
62
210
350
30
300
250*1

250
400
300
400
250
400
400
250
400
400
200
250*1

250
250
250
250
250
250
250
250
1000
250
250
1000

U U
U T U
U T U

U U I
U U I

I
I

I U
I U

U U
U U

P2

865

20 30*1

300*1

250*1

1000 U U

SW1 1050 20 57
SW2 1380 20 8
SW3 1640*4 200 3
SW4 2210 50 1.9

248
103
50
20

U T

U U I

I

I U

U U U C C C C C C C C

E T M M U U III E

U T U U U U I
U U
U R
I

I
I

I U
I R

U
I
E I U C C C C C C C CIMUIU U U C C C C C C C C
R R
E

I

I R

R R

500
1000
150
1000
57
250 U T
211(TBD) 1000 U T

U R

I

U
U

U
U E
U

I
I
I

I T E
I I U
I T
U
E
I T
U U E
E
T
U M U
T
U U E
T
U M E UI T M
I I E IR UIIM
I I I IR U
R RE

M C C M C UUU R U E U U C C
C
U
U U
M

U
I R
U
I R
U
I U
U
I U
U C I R
U
I U
U
I R
C I

R
R
U
U
R
U
R

I
C I

U
U
U
U
U
U C U
U
U
R C U
R
U
R C U

U I

U M
R R
U U U S U U S U M S U
U U U S S S S E S S U

U U U S S S S U S R U

U U U S M S S U U R U
R
R

R
I

I

R C

I

I

R
R

R
I

T1

10.8*2 0.7*2 300 180~340

0.2

500

U

U

U U

U C U

U U

I

I

M I

T2

12.0*2 0.7*2 300 180~340

0.2

500

U

M

U U

U C U

U

R R

E

R

U U U U S S R S U S S U
M U C C C C C C C C C
M U U U C C C R U C C UUURM U U U U M S S S S S S
E U

R

M

M: Most essential, E: essential, U: used channel, T: correction targets, R: future research, I: indirect use, C: cloud detection, S: Snow detection*1: defined as intensity of non-polarized light, *2 :Unit is m, *3: 1km in the open ocean, *4: the light limit is at 1740nm
Green: Succession of GLI standard products, Red: New standard products, and White: research products.

9

3. SGLI Ocean Science Plan
3.3 SGLI ocean standard products definitions and development methods•Normalized Water Leaving Radiance (NWLR) and Atmospheric Correction Parameters (ACP)•Definition: Standardized radiance of the SGLI spectral channels leaving from a sea surface in the case of atmospherictransmittance 1.0 , the solar zenith angle zero and the sun-earth distance 1AU. The reflective ingredient of a sea
surface is not included (mW/cm2/str/um). This is same as OCTS, GLI, SeaWiFS, and MODIS.
•Development: Evaluation and improvement of the aerosol processing by the match up of a past satellite and in situ
optical observations.
•Photosynthetically Available Radiation (PAR)•Definition: daily average of the light at wavelengths from 400nm to 700nm which phytoplankton uses for photosynthesisby Ein/m2/day.
•Development: Improvement of treatment of the daily variation of cloud amount, and evaluation using ground PAR
observations•CHLorophyll-A concentration (CHLA)•Definition: phytoplankton chlorophyll-a concentration by mg/m3•Development: Evaluation and improvement of bio-optical models (formulas) by in situ bio-optical observations•Suspended Solid concentration (SS)•Definition: Filter dry weight by g/m3 (total suspended matter)•Development: Same as CHLA
•absorption of Colored Dissolved Organic Matter (CDOM)•Definition: attenuation coefficient (m-1) of the colored dissolved organic matter at 440nm (TBD)•Development: Same as CHLA
•Sea Surface Temperature (SST)•Definition: bulk sea surface temperature (observed by drifting buoy at 1-m) by degree C•Development: Atmospheric correction, and cloud detection accuracy evaluation and improvement by comparison withexisting satellite data and in-situ SST data distributed on GTS or the Internet. Pre-launch evaluation of the atmosphericcorrection coefficient equivalent to the SGLI spectrum response by a radiation transfer simulation.

10

3. SGLI Ocean Science Plan
3.4 SGLI ocean research products definitions and development methods• Euphotic Zone Depth (EZD)• Definition: Total direction illumination (observation is cosine) defines by PAR as depth which becomes 1% (denominator: E0-).
• Development: Formulize relations between nLw and EZD calculated by in-situ measurements of underwater downward irradiance.
• Inherent Optical Properties (IOP)• Meaning: It can be used for the primary productivity model, plankton classification presumption, etc.
• Development: Formulize relations between in-situ bio-optical observations, such as CHLA, SS and CDOM, and a scattering and absorption
coefficients, and evaluate applicability to satellite data.
• multi sensor Merged Ocean Color parameters (MOC)• Definition: Data sets which combined with the product of other satellites and improved time resolution• Development: Same as an ocean color product peculiar to SGLI.
• multi sensor Merged Sea Surface Temperature (MSST)• Definition: Data sets which combined with the product of other satellites and improved time resolution• Development: Same as an ocean color product peculiar to SGLI.
• Ocean Net Primary Productivity (ONPP)• Definition: Net primary productivity by phytoplankton (breathing respiration is not taken into consideration)• Development: Evaluation of the applicability by the satellite data based on presumption and improvement of the parameter of thebiological production model by in situ observation, and processing of the existing satellite data.
• PHytoplankton Functional Type (PHFT)• Definition: The phytoplankton existence rate for every functions, such as nitrogen fixation, silicon fixation, and carbon dioxide discharge.
It grasps what kind of function plankton with exists, and it is used for climate change analyses, such as cloud nucleus formation.
• Development: The relation of the functional classification and the water-leaving radiance spectrum in in situ observation is put in a
database (the existence rate for every phytoplankton function and NWLR are associated), and it applies to satellite data.
• Red TiDe (RTD)• Definition: The coloring phenomenon which man distinguishes from red tide
• Development: From correspondence with in situ visual observation, classification observation, and the observation example by theexisting satellite, the relation between a nLw spectrum, and red tide and its classification is typified.

11

4. Summary• JAXA is planning Global Climate Observation Mission (GCOM), which consists of
GCOM-W and GCOM-C satellite series.
• GCOM-C carries a radiometer of visible-infrared, middle-resolution, and global
and frequent observation, Second generation GLI (SGLI).
• Aiming to the target launch year 2011, we have started sensor Breadboard
Model (BBM) study (design and trial manufacture) from autumn in 2005. (Thismay be delayed by today's difficulty of financial resources.)• We are trying to undergo the evaluation of mission approval from points of viewof social benefit, costs and reality (the evaluation is very important for the next
procedures).
• JAXA is looking for data requirement from operational agencies or user groups(IOCCG can be?) making commitment to use, and the present use examples, in orderto make a decision of the mission approval.

• We hope that SGLI science project, which does not exist yet, can support IOCCG
to promote application and merger of SGLI ocean-colour products.

12