APPENDIX COVERVIEW OF THE GLOBAL CHANGE OBSERVATIONMISSION (GCOM)

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1.

Introduction

Comprehensive observation, understanding, assessment, and prediction of global climate change arecommon and important issues for all mankind. This is also identified as one of the importantsocio-economic benefits by the 10-year implementation plan for Earth Observation that was adopted by
the Third Earth Observation Summit to achieve the Global Earth Observation System of Systems(GEOSS). International efforts to comprehensively monitor the Earth by integrating various satellites,
in-situ measurements, and models are gaining importance. As a contribution to this activity, the Japan
Aerospace Exploration Agency (JAXA) plans to develop the Global Change Observation Mission(GCOM). GCOM will take over the mission of the Advanced Earth Observing Satellite-II (ADEOS-II)and develop into long-term monitoring of the Earth.
As mentioned in the fourth assessment report of the Intergovernmental Panel on Climate Change(IPCC), warming of the climate system is unequivocal as is now evident from observations of increases in
global average air and ocean temperatures and widespread melting of snow and ice. However, climatechange signals are generally small and modulated by natural variability, and are not necessarily uniform
over the Earth. Therefore, the observing system of the climate variability should be stable, and should
cover a long term over the entire Earth.
To satisfy these needs, GCOM consists of two medium-size, polar-orbiting satellite series and multiple
generations (e.g., three generations) with one-year overlaps between consecutive generations forinter-calibration. The two satellite series are GCOM-W (Water) and GCOM-C (Climate). Two
instruments were selected to cover a wide range of geophysical parameters: the Advanced Microwave
Scanning Radiometer-2 (AMSR2) on GCOM-W and the Second-generation Global Imager (SGLI) on
GCOM-C. The AMSR2 instrument will perform observations related to the global water and energy cycle,
while the SGLI will conduct surface and atmospheric measurements related to the carbon cycle andradiation budget. This chapter presents an overview of the mission objectives, observing systems, and data
products of GCOM.
2.

Mission Objectives

The major objectives of GCOM can be summarized as follows.
- Establish and demonstrate a global, long-term Earth-observing system for understanding climate
variability and the water-energy cycle.
- Enhance the capability of climate prediction and provide information to policy makers throughprocess studies and model improvements in concert with climate model research institutions.
- Construct a comprehensive data system integrating GCOM products, other satellite data, and in-situ
measurements.
- Contribute to operational users including weather forecasting, fishery, and maritime agencies by
providing near-real-time data.
- Investigate and develop advanced products valuable for understanding of climate change and water
cycle studies.
Detailed explanations of the objectives are as follows.
(1) Understanding global environment changes
A) Establish and demonstrate a global, long-term Earth-observing system that is able toobserve valuable geophysical parameters for understanding global climate variability andC-2

water cycle mechanisms.
B) Contribute to improving climate prediction models by providing accurate values of model
parameters.
C) Clarify sinks and sources of greenhouse gases.
D) Contribute to validating and improving climate prediction models by forming acollaborative framework with climate model institutions and providing long-term
geophysical datasets to them.
E) Detect trends of global environment changes (e.g., global warming, vegetation changes,
desertification, variation of atmospheric constituents, wide area air pollution, and depletionof ozone layers) from long-term variability of geophysical parameters by extracting
short-term (three- to six-year) natural variability.
F) Advance process studies of Earth environmental changes using observation data.
G) Estimate radiative forcing, energy and carbon fluxes, and albedo by combining satellite
geophysical parameters, ground in-situ measurements, and models.
H) Advance the understanding of the Earth’s system through the activities above.
I) Contribute to an international environmental strategy utilizing the results above.
(2) Direct contribution to improving people’s lives
A) Improvement of weather forecast accuracy (particularly typhoon track prediction, localized
severe rain, etc.).
B) Improvement of forecast accuracy for unusual weather and climate.
C) Improvement of water-route and maritime information.
D) Provision of fishery information.
E) Efficient coastal monitoring.
F) Improved yield prediction of agricultural products.
G) Monitoring and forecasting air pollution including yellow dust.
H) Observation of volcanic smoke and prediction of the extent of the impact.
I) Detection of forest fires.
3.

Observing Systems

3.1. Overall concept
As mentioned in the previous section, the entire GCOM will consist of two satellite series spanning
three generations. However, a budget will be approved for each satellite. Currently, only the GCOM-W1
satellite has been approved for actual development as the first satellite in the GCOM series. Both
GCOM-W1 and GCOM-C1 satellites will be medium-size platforms that are smaller than the ADEOS-II
satellite. This is to reduce the risk associated with large platforms having valuable and multiple observing
instruments. Also, since the ADEOS-II problem was related to the solar paddle, a dual solar-paddle
design was adopted for both satellites. To assure data continuity and consistent calibration, follow-on
satellites will be launched so as to overlap the preceding satellite by one year. The concept is summarized
in Fig. 1.
Japanese Fiscal Year 2011

1-year

GCOM-W1
GCOM-W2

LaunchGCOM-W3
GCOM-C1
GCOM-C2

LaunchGCOM-C3

Fig. 1. GCOM concept
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3.2. GCOM-W1 and AMSR2 instrument
Figure 2 presents an overview of the GCOM-W1 satellite; its major characteristics are listed inTable 1. GCOM-W1 will carry AMSR2 as the sole onboard mission instrument. The satellite will
orbit at an altitude of about 700km and will have an ascending node local time of 1330, to maintainconsistency with Aqua/AMSR-E observations.

Fig. 2. Overview of GCOM-W1 satellite

TABLE 1
MAJOR CHARACTERISTICS OF GCOM-W1 SATELLITE
Instrument

Size

Advanced Microwave Scanning Radiometer-2 (AMSR2)
Sun-synchronous orbit
Altitude: 700km (over the equator)
5.1m (X) * 17.5m (Y) * 3.4m (Z) (on-orbit)

Mass

1991kgPower

More than 3880W (EOL)

Launch

JFY2001 by H-IIA Rocket

Design Life

5 years

StatusPhase-D

Orbit

Figure 1 presents an overview of the AMSR2 instrument in two different conditions. Also, basic
characteristics including center frequency, bandwidth, polarization, instantaneous field of view(FOV), and sampling interval are indicated in Table 2. The basic concept is almost identical to thatof AMSR-E: a conical scanning system with a large offset parabolic antenna, feed horn cluster torealize multi-frequency observation, external calibration with two temperature standards, andtotal-power radiometer systems. The 2.0m diameter antenna, which is larger than that of AMSR-E,
provides better spatial resolution at the same orbit altitude of around 700km. The antenna will be
developed based on the experience gained from the 2.0m diameter antenna for ADEOS-II AMSR
except the deployment mechanism. For the C-band receiver, we adopted additional 7.3GHz
channels for possible mitigation of radio-frequency interference. An incidence angle of 55 degrees(over the equator) was selected to maintain consistency with AMSR-E. The swath width of 1450km
and the selected satellite orbit will provide almost complete coverage of the entire Earth’s surface
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within two days independently for ascending and descending observations.

Fig. 3. Sensor unit of AMSR2 instrument in deployed (left) and stowed (right) conditions.
TABLE 2
MAJOR CHARACTERISTICS OF AMSR2 INSTRUMENT
Parameter
Center Frequency (GHz)

Performance and characteristics
6.925/7.3

10.65

18.7

23.8

36.5

89.0

350

100

200

400

1000

3000

Bandwidth (MHz)Polarization
NE∆T (K)1

Vertical and Horizontal polarization< 0.34/0.43< 0.70< 0.70

Dynamic range (K)< 0.60< 0.70< 1.20/1.40 2

2.7 to 340

Nominal incidence angle (deg.)

55.0

55.0/54.5 2

Beam width (deg.)

1.8

1.2

0.65

0.75

0.35

0.15

IFOV (km) Cross-track x along-track

35x62

24x42

14x22

15x26

7x12

3x5

Approximate sampling interval (km)10

5Swath width (km)> 1450Digital quantization (bits)

12

Scan rate (rpm)40

3.3. GCOM-C1 and SGLI instrument
Figure 4 gives an overview of the GCOM-C1 satellite; its major characteristics are listed in Table 3.
GCOM-C1 will carry SGLI as the sole mission onboard instrument. The satellite will orbit at an altitude
of about 800km; the descending node local time will be 1030, to maintain a wide observation swath andreduce cloud interference over land.

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Fig. 4. Overview of GCOM-C1 satellite
TABLE 3
MAJOR CHARACTERISTICS OF GCOM-C1 SATELLITE
Instrument

Size

Second-generation Global Imager (SGLI)
Sun-synchronous orbit
Altitude: 798km (over the equator)
4.6m (X) * 16.3m (Y) * 2.8m (Z) (on orbit)

Mass

2093kgPower

More than 4000W (EOL)

Launch

JFY2014 by H-IIA Rocket

Design Life

5 years

StatusPhase-C

Orbit

The SGLI instrument has two major new features: 250m spatial resolution for most of the visible
channels and polarization/multidirectional observation capabilities. The 250m resolution will
provide enhanced observation capability over land and coastal areas where the influences of humanactivity are most obvious. The polarization and multidirectional observations will enable us toretrieve aerosol information over land. Precise observation of global aerosol distribution is a key for
improving climate prediction models.
SGLI consists of two major components: the Infrared Scanner (IRS) and the Visible and
Near-infrared Radiometer (VNR). An overview of the SGLI instrument is shown in Fig. 5 for theentire radiometer layout, IRS, and VNR components. Also, requirements for sensor performance arelisted in Tables 4 and 5. VNR can be further divided into two components: VNR-Non Polarized(VNR-NP) and VNR-Polarized (VNR-P). VNR-NP and VNR-P are the 11-channel multi-band
radiometer and the polarimeter with three polarization angles (0, 60, and 120 degrees). VNR-P has atilting function to meet the scatter angle requirement from aerosol observation. The IRS is an
infrared radiometer covering wavelengths from 1µm to 12µm. It consists of short infrared (SWI;
1.05 to 2.21µm) and thermal infrared (TIR 10.8 and 12.0µm) sensors. It employs a scanning mirror
system with a 45-degree tilted flat mirror rotating continuously to realize an 80-degree observation
swath and calibration measurement in every scan.
Through intensive discussions and optimizing studies, the number of SGLI channels wasdecreased from the 36 channels of GLI aboard ADEOS-II to 19 channels, while the number of
SGLI standard products will increase compared to those of GLI.
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Fig. 5. Overview of SGLI radiometer layout (upper), IRS instrument (lower-left), and VNR radiometers(lower-right).
TABLE 4
SGLI MAJOR PERFORMANCE REQUIREMENTS
Item
Spectral Bands

Scan Angle
Swath width
Instantaneous field of view
(IFOV) at nadir
Observing direction
Quantization
Absolute
Accuracy
Lifetime

Calibration

Requirement
VNR-NP : 11CH 380-865nm
VNR-P: 2CH 673.5, 868.5nm / 0, 60, 120deg Polarization
IRS SWI : 4CH 1.05-2.21µm
IRS TIR : 2CH 10.8, 12.0µm
VNR-NP: 70deg (Push broom scanning)
VNR-P: 55deg (Push broom scanning)
IRS SWI/TIR : 80deg (45deg rotation mirror scanning)
1150km for VNR-NP/P
1400km for IRS SWI/TIR
VNR-NP: 1000m(VN9CH), 250m
VNR-P
: 1000m
IRS SWI: 250m(SW3CH), 1000m(SW1,2,4CH)
IRS TIR: 500m±45 degrees in along track direction for VNR-P
Nadir for VNR-NP, IRS SWI, and IRS TIR
12bit
VNR : ≤3% IRS : ≤5% TIR : ≤0.5K
5 Years

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TABLE 5
SGLI OBSERVATION REQUIREMENT DETAILSCH
VNR-NPVNR-PIRS SWIIRS TIR

4.

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

λ
∆λ
nm: VNR, IRS SWIµm: IRS TIR
380
10
412
10
443
10
490
10
530
20
565
20
673.5
20
673.5
20
763
12
868.5
20
868.5
20
673.5
20
868.5
20
1050
20
1380
20
1630
200
2210
50
10.8
0.74
12.0
0.74

IFOV
m
250
250
250
250
250
250
250
250
1000
250
250
1000
1000
1000
1000
250
1000
500
500

SNR
SNR: VNR, IRS SWI
NE∆T(K): IRS TIR
250
400
300
400
250
400
400
250
1200
400
200
250
250
500
150
57
211
0.2
0.2

L (for SNR)
W/m2/sr/µm
60
75
64
53
41
33
23
25
40
8
30
25
30
57
8
3
1.9
300 (K)300 (K)

Products

Geophysical products made available by GCOM-W1 and GCOM-C1 are listed in Tables 6 and 7.
There are two categories of data products: standard product and research product. A “standard”
product is defined as a product with proven accuracy that is to be operationally processed anddistributed. In contrast, a “research” product is a prototype for a standard product and is processedon a research basis. Both tables indicate standard products with shading.

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TABLE 6
GEOPHYSICAL PRODUCTS OF GCOM-W1
Product

Areas

Grid
(km)

Integrated
water vapor

Global,over ocean

Integrated
cloud liquidwater

Accuracy 1
Range

Data releasethresholdStandard

Goal

15±3.5 kg/m2±3.5 kg/m2±2.0 kg/m2

0-70 kg/m2

Vertically integrated (columnar) water vapor
amount. Except sea ice and precipitating areas.

Global,over ocean

15±0.10 kg/m2±0.05 kg/m2±0.02 kg/m2

0-1.0 kg/m2

Vertically integrated (columnar) cloud liquidwater. Except sea ice and precipitating areas.

Precipitation

Global, except
cold latitudes

15

Ocean ±50 % Ocean ±50% Ocean ±20%Land ±120 % Land ±120 % Land ±80 %0-20 mm/h

Surface precipitation rate. Accuracy is defined as
relative error (ratio of root-mean-square error toaverage precipitation rate) in 50km grid average.

Sea surface
temperature

Global,over ocean

50±0.5 °C±0.5 °C±0.2 °C-2-35 °C

Except sea ice and precipitating areas. Goal
accuracy is defined as monthly mean bias error in
10 degrees latitudes.

Sea surface
wind speed

Global,over ocean

15±1.5 m/s±1.0 m/s±1.0 m/s

0-30 m/s

Sea iceconcentration

Polar region,over ocean

15

±10 %

±10 %

±5 %

0-100 %Snow depth

Land

30

±20 cm±20 cm±10 cm0-100 cm

Except ice sheets and dense forest areas. Accuracy
is expressed in snow depth and defined as mean
absolute error of instantaneous observations.

0-40 %

Volumetric water content over global land areas
including arid and cold regions, except areas
covered by vegetation with 2kg/m2 waterequivalent. Accuracy is defined as mean absolute
error of instantaneous observations.

Soil moisture

Land

50

±10 %

±10 %

±5 %

Except sea ice and precipitating areas.

Accuracy is expressed in absolute value of sea ice
concentration (%).

1 Accuracy is defined as root-mean-square error of instantaneous values unless otherwise stated. Assumed validation methodologies
are not explained here.

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TABLE 7
GEOPHYSICAL PRODUCTS OF GCOM-C1 (1/3)
Area Group

commonRadiance

Product

Category

GLI
Day/night
heritage*1

Production unit

Grid size

TIR and land 2.2µm:
TOA radianceboth,A(non-Pol)(including system geometric Standard
Scene
Other VNR, SWI:
B(Pol)
correction)
daytime (+special
operation)
Precise geometric correction

Surface
Atmospheric correctedreflectance reflectance (incl. clouddetection)
Vegetation index

Release threshold*2Standard accuracy*2

Target accuracy*2

VNR,SWI Land/coast:
VNR,SWI: 5% (absolute),
250m,
offshore: 1km,
Radiometric 5% (absolute)*3 1% (relative) *3
polarimetory:1km
Geometric<1 pixel
TIR: 0.5K (@300K)
TIR Land/coast: 500m,
Geometric<0.5 pixel
offshore: 1km

VNR,SWI: 3% (absolute),
0.5% (relative) *3
TIR: 0.5K (@300K)
Geometric<0.3 pixel

LandStandardA

Both

Scene, Global (mosaic 1, 16
days, month)

250m<1pixel<0.5pixel<0.25pixel

Standard

B

Daytime

Scene, Global (1, 16 days,
month)

250m

0.3 (<=443nm),
0.2 (>443nm) (scene) *7

0.1 (<=443nm),
0.05 (>443nm) (scene) *7

0.05 (<=443nm),
0.025 (>443nm) (scene)*7

Standard

A
Daytime

Scene, Global (1, 16 days,
month)

250m

Daytime

Scene, Global (1, 16 days,
month)

1km
1km
250m, 1km

Grass: 25%, forest: 20% Grass: 20%, forest: 15%
Grass: 10%, forest: 10%(scene)(scene)(scene)Grass: 50%, forest: 50%
Grass: 30%, forest:20%
Grass: 20%, forest: 10%
Grass: 50%, forest: 50%
Grass: 30%, forest:30%
Grass: 20%, forest: 20%
Grass: 50%, forest: 100%
Grass: 30%, forest: 50%
Grass: 10%, forest: 20%
Grass and forest: 40% (scene) Grass and forest: 20% (scene) Grass and forest: 10% (scene)
Grass and forest: 30% (scene) Grass and forest: 20% (scene) Grass and forest: 10% (scene)

Scene, Global (1, 16 days,
month)
Global (month, year)

500m<3.0K (scene)<2.5K (scene)<1.5K (scene)

1km

N/A

N/A

Vegetation fAPAR
and carbon Leaf area index
cycle
Above-ground biomass
Vegetation roughness index
Shadow index

Standard
Standard
Standard
Standard
Standard

B
B
B
B
B

Temperature Surface temperatureStandard

B

BothLand net primary production ResearchC

DaytimeWater stress trend

ResearchC

N/A

Scene, Global (1, 16 days,
month)

500m

N/A

N/A

ResearchB

Both*12

Scene

500m

N/A

N/A

Land cover typeResearch

B

Daytime

250m

N/A

N/A

Land surface albedo

ResearchB

N/A

Global (month, season)
Scene, Global (1, 16 days,
month)

30% (yearly)
10% *13 (error judgmentrate)
20% *14 (error judgmentrate)
30% (error judgment rate)

1km

N/A

N/A

10%

Cloud flag/Classification

StandardA

Both

Scene, Global（1 day, month）

1km

Classified cloud fraction
Cloud top temp/height
Water cloud OT/effective
radiusIce cloud optical thickness
Water cloud geometrical
thickness
Aerosol over the oceanLand aerosol by near UVStandard
Standard

A
A

DaytimeBothGlobal （1 day, month）

Standard

B

Daytime

Scene, Global （1 day, month）

Application Fire detection index

Cloud
Atmosphere
Aerosol

RadiationbudgetStandard

B

Daytime

Scene, Global（1 day, month）

10%
(with
whole-skyIncl. below cloud amount
Incl. below cloud amountcamera)*9*920% (on solar irradiance)
15% (on solar irradiance)
10% (on solar irradiance)*9*4*51K
3K/2km (top temp/height)
1.5K/1km (temp/height)*5
10%/30%(Cloud100% as CLW*7
50%*7 / 20%*8
OT/radius)*6
30%*6
70%*8
20%*8

ResearchC

Daytime

Scene, Global （1 day, month）

N/A

Standard
Standard

A
B

DaytimeDaytime

Scene, Global （1 day, month）

Aerosol by Polarization

Standard

B

Daytime

Scene, Global （1 day, month）

Long-wave radiation flux

ResearchC

Daytime

Scene, Global （1 day, month）

Short-wave radiation flux

Research

B

Daytime

Scene, Global （1 day, month）

Scene, Global （1 day, month）

1km (scene),
Scene, Global （1 day, month） 0.1deg (global)

C-10

N/A

300m

0.05 (scene τa_670,865)
0.1 (Monthly τa_670,865)*10 0.1(scene τa_670,865)*10
0. 1(scene τa_380 )0.15 (Monthly τa_380)*10 0.15 (scene τa_380)*10
0.15(Monthly
0.15 (scene τa_670,865)*10 0.1 (scene τa_670,865)
τa_670,865)*10
Downward 10W/m2, upward
N/A
N/A
15W/m2 (monthly)
Downward 13W/m2, upward
N/A
N/A
10W/m2TABLE 7
GEOPHYSICAL PRODUCTS OF GCOM-C1 (2/3)
Area Group

Product

Category

Normalized water-leaving
Standard
radiance (incl. clouddetection)
Atmospheric correction
Standard
Ocean color parameter
Photosynthetically available
Standard
radiation
Euphotic zone depth

In-water

GLI
Day/night
heritage*1
B
DaytimeA
B

Chlorophyll-a concentration Standard

A

Ocean

Inherent optical properties
Temperature Sea-surface temperature
Ocean net primary
productivity

Standard

Scene, Global (1, 8 days,
month)A

DaytimeDaytimeDaytime

Scene, Global (1, 8 days,
month)
Scene, Global (1, 8 days,
month)

C

Daytime

Scene, Global (1, 8 days,
month)

StandardA

Both

Scene, Global (1, 8 days,
month)

Daytime

Scene, Global (1, 8 days,
month)

Phytoplankton functional
type

ResearchC

Daytime

Scene, Global (1, 8 days,
month)

Coast: 250m
Offshore: 1km
Global: 4-9km

50% (<600nm)
30% (<600nm)
0.5W/m2/str/um (>600nm) 0.25W/m2/str/um (>600nm)

N/A−60 to +150% (offshore)−60 to +150% (offshore)

Red tide

Research

B

Daytime

Scene, Global (1, 8 days,
month)

B

DaytimeA

Both

Coast: 500m
Others: Same as above
Coast: 500m
Others: Same as above

Coast: 250m
Others: Same as above

Application

Area, Global (1, 8 days, month)

Coast: 250m
Offshore: 1km
250m (scene),(global)
250m
1km

CryosphereA

DaytimeA
B

DaytimeDaytime

Scene, Global (1, 16 days,
month)
Area (1day)
Global (16 days, month)

B

DaytimeArea (1, 8 days)

250m

A

Daytime

Scene, Global (1, 16 days,
month)

B

Daytime

Scene, Global (1, 16 days,
month)

500m (scene),(global)250m (scene),(global)B

Daytime

Scene, Global (1, 16 days,
month)

1km

Snow grain size of top layer ResearchC

DaytimeSnow and ice albedo

B

Daytime

Scene, Global (1, 16 days,
month)
Global (1, 16 days, month)

250m (scene),(global)1km

Research

60% (443~565nm)−60 to +150% (offshore)

Research

multi sensor merged ocean
Researchcolor
multi sensor merged SST
Research
Snow and Ice covered area
Standard(incl. cloud detection)
Okhotsk sea-ice distribution Standard
Area/
distribution Snow and ice classification Research
Snow covered area in forests
Researchand mountains
Snow and ice surface
Standard
Temperature
Snow grain size of shallow
Standard
layer
SurfaceSnow grain size ofproperties
Research
subsurface layerStandard accuracy*2

20% (10km/month)

Scene, Global (1, 8 days,
month)AC

Release threshold*2

80% (AOT@865nm)

Standard

Research

Grid sizeA

Research

Suspended solid
concentration
Colored dissolved organic
matterProduction unit

C-11

1km

50% (AOT@865nm)
15% (10km/month)

30% (AOT@865nm)
10% (10km/month)

N/A

30%

−60 to +150%−35 to +50% (offshore), −50
to +100% (coast)−60 to +150%−60 to +150%−50 to +100%−50 to +100%

N/A

N/A

a (440): RMSE<0.25, bbp(550): RMSE<0.25

0.8K (daytime)

0.8K (day & night time)

0.6K (day and night time)

N/A

N/A

70% (monthly)

N/A

N/A

error judgment rate of large/
small phytoplankton
dominance<20%; or error
judgment rate of the dominantphytoplankton functionalgroup <40%

N/A

N/A

error judgment rate <20%

N/A

N/A

N/A

N/A

−35 to +50% (offshore), −50
to +100% (coast)
0.8K (day & night time)

10% (vicarious val with other 7%
sat. data)
5%
N/A

5%

N/A

30%

10%
N/A

N/A

1km 5K (vicarious val with other2K
sat. data and climatology)
1km 100% (vicarious val. with50%
climatology between temp-size)
1km

Target accuracy*2

3%
10%

1K
30%

N/A

N/A

50%

N/A

N/A

50%

N/A

N/A

7%

TABLE 7
GEOPHYSICAL PRODUCTS OF GCOM-C1 (3/3)
Area Group
Cryosphere

Surfaceproperties
Boundary

GLI
Day/night
heritage*1

Product

Category

Snow impurity

Research

B

DaytimeIce sheet surface roughness Research
Ice sheet boundary
Researchmonitoring

C
B

Production unit

Grid size

Daytime

Scene, Global (1, 16 days,
month)
Area (Season)

250m (scene),(global)1km

DaytimeArea (Season)

250m

1km

Release threshold*2Standard accuracy*2

Target accuracy*2

N/A

N/A

50%

N/A

N/A

0.05 *15

N/A

N/A

<500m

Common notes:*1. Heritage levels from ADEOS-II/GLI study are shown by A-C; A: high heritage, B: Remaining issues, C: new or many issues remaining to be resolved*2. The “release threshold” is minimum levels for the first data release at one year from launch. The "standard" and "research" accuracies correspond to full and extra success criteria of the mission. Accuracies
are basically shown by RMSE.
Radiance data notes:*3. Absolute error is defined as offset + noise; relative error is defined as relative errors among channels, FOV, and so on. Release threshold of radiance is defined as estimated errors from vicarious, onboard
solar diffuser, and onboard blackbody calibration because of lack of long-term moon samples
Atmosphere notes:*4. Vicarious val. on sea-surface temperature and comparison with objective analysis data
*5. Inter comparison with airplane remote sensing on water clouds of middle optical thickness*6. Release threshold is defined by vicarious val. with other satellite data (e.g., global monthly statistics in the mid-low latitudes)*7. Comparison with cloud liquid water by in-situ microwave radiometer*8. Comparison with optical thickness by sky-radiometer (the difference can be large due to time-space inconsistence and large error of the ground measurements)*9. Comparison with in-situ observation on monthly 0.1-degree*10. Estimated by experience of aerosol products by GLI and POLDER
Land data notes:*11. Defined with land reflectance~0.2, solar zenith<30deg, and flat surface. Release threshold is defined with AOT@500nm<0.25*12. Night time 250m product can be produced by special observation requests of 1.6µm channel*13. Evaluate in semiarid regions (steppe climate, etc.)*14. Fires >1000K occupying >1/1000 on 1km pixel at night (using 2.2um of 1 km and thermal infrared channels)
Cryosphere notes:*15. Defined as height/width of the surface structures

C-12