KORDI's requirements for MERIS CASE-2 water monitoring - Yu ...

KORDI’s s Requirements for MERIS CASE-2
water monitoring
Yu-Hwan Ahn
Korea Ocean Satellite Center (KOSC), KORDI

General Ocean Environment of Korean Seawaters
Yellow Sea
Yellow Sea
East Sea
East Sea
Water depths
- East sea(Japan Sea) : ~3km
- Yellow Sea : ~ 80m
- East China Sea : ~ 200m
Turbid water
East China East Sea China Sea

General Ocean Environment of Korean Seawaters
Yellow Sea
East Sea
Yellow color ;
- Shallow &
- Turbid waters
Turbid water
East China Sea

General Ocean Environment of Korean Seawaters
Yellow Dust problems
in O.C monitoring
1. Optical properties of
waters are influenced
by the Yellow Dust
2. It’s hard to remove
the atmospheric signal
from total signal
in addition ;
Yellow dust events are
considered as a very
serious natural hazard
in Korea for people’s
health

General Ocean Environment of Korean Seawaters
Phytoplankton Spring
Bloom at dumping site
27 Mar. 2002
SeaWiFS CHL
Out of existence of the
Phytoplankton Bloom
10 May. 2001
SeaWiFS CHL

General Ocean Environment of Korean Seawaters
• Turbid water from ECS
- low salinity
- impact on coastal fish farming
A
B
• Source of Suspended
sediment in the East China Sea
A : Wind driven Re-suspended
sediment from bottom ←
Yangtze river
B : Tidal current Re-suspension

General Ocean Environment of Korean Seawaters
SeaWiFS Chl-a image
(Sep.16.2003)
KOREA
Pohang
Jin-hae
bay
• Redtide in the Yellow Sea
• Extension of Redtide
to the East-Sea

General Ocean Environment of Korean Seawaters
SeaWiFS (12 Jul. 2001)
Red tide Index
SeaWiFS (22 Aug.
2001)
Red tide Index
• Phytoplankton bloom monitoring by Redtide Index(RI) in Yellow Sea

General Ocean Environment of Korean Seawaters
Green Algae Bloom
• Green Algae Bloom in Yellow/East China Sea(Korea/China)
• Bloom might have been originated from the Sansha Dam(Three Gorges Dam)
• Total removal quantity in Jeju : 196 ton
(Beach : 43 ton, coast : 153 ton)
(32° 35′ 225″N, 126° 35′ 340″E)

General Ocean Environment of Korean Seawaters
Green Algae in China
Total removal quantity in Qingdao : about 1 million ton
Sea
During 2008 Beijing Olympic Game, sailing
stadium of Qingdao was attacked by green
algae.

General Ocean Environment of Korean Seawaters
• Green Algae Monitoring by MODIS

Ocean Optical Properties of Korean Seawaters
• Yellow Sea, ECS & Coastal Area : CASE-II water
• South Sea & ECS : Mixed area of CASE-I and CASE-II water
• East Sea(Japan Sea) : CASE-I water
1 :1 line

Ocean Optical Properties of Korean Seawaters
• CHL : 0.1 – 100 mg/m 3 (redtide area)
• SS : 0.2 – 100 g/m 3 (in China coastal area, 1000 g/m 3 )

Ocean Optical Properties of Korean Seawaters
• IOPs & AOPs spectrum in the Yellow Sea and coastal area

Ocean Optical Properties of Korean Seawaters
• IOPs & AOPs spectrum shapes in the Redtide area

KORDI’s proposal for
CoastColour Project
(CASE-II water techniques)

Required parameters from CC MERIS Data
IOP : Light absorption & backscattering coefficients
AOP
-nL w
: Normalized water leaving radiance
-R rs
: Remote sensing reflectance
- K coefficients in blue & green bands
Water’s main parameters
- CHL : Chlorophyll concentration (mg/m 3 )
* Band ratio & Fluorescence technique
- SS : Suspended solid particle matter concentration (g/m 3 )
- CDOM : Absorption coefficient of dissolved organic matter at 400 nm (m -1 )
Water’s sub-parameters
- Algal bloom index (Redtide index; 0 – 1 or 1 - 10) & green floating algae monitoring
- Water quality(pollution) index (1 – 5)
- Water current vector (cm/sec)
- Underwater visibility (m)
Etc
- Atmospheric optical thickness - Yellow dust concentration in Atmosphere

Error requirements for CC MERIS Data (I)
Total radiance in orbit (TL) : ±5%
Atmospheric correction in turbid waters : ±5%
Water leaving radiance (Lw) : ±5%
-----------------------------------------------------------------
Total error : within ±5%

Algorithms for CC MERIS Data (I)
- Empirical & semi-analytical methods
- Neural Network etc
* Pure analytical method (future hyper-spectral sat.)
- least requirement : 20 bands,
- optimal bands number : ~60bands

Error Requirements for CC MERIS Data (II)
Parameters
Units
Clear water
(Error in Av.)
Turbid water
(Error in Av.)
nL w mW/cm 2 /μm/sr ±4 % ± 5 %
R rs sr -1 ±4 % ± 5 %
CHL mg/m 3 ±10 % ± 20 %
SS g/m 3 ± 10% ± 10 %
CDOM m -1 ±15% ± 30 %
nL w
: Normalized Water leaving radiance
R rs
: Remote sensing reflectance
CHL : Chlorophyll concentration
SS : Suspended solid particle matter concentration
CDOM : Absorption coefficient of dissolved organic matter at 400 nm

Error Requirements for MERIS Data (III)
Parameters
RI
(Algal bloom
Index)
Water Pollution
Index
Units
Clear water
(Error in Av.)
Turbid water
(Error in Av.)
Range 0.0 – 1.0 % %
Range 1 - 5 % %
Water current m/sec ±20 % ± 20 %
Underwater
Visibility
m ± 10% ± 10 %
CHL-FL mg/m 3 ±10 % ±10 %

KORDI’s s Proposals for CC project (I)
‣ An offer of in-situ Ocean Optical and Environmental Data in the
Korean Seawaters (Date : 2000 – 2008) for the development of the
CoastColour algorithms / Collaboration with CC project.
• L w (λ), E d (λ), R rs (λ) data obtained from field spectroradiometer
• a ph (λ), a ss (λ), a dom (λ) data
• CHL and SS data obtained with optical parameters

KORDI’s Collaboration Proposals (II)
‣ Offering of Near Real-Time in-situ Ocean Optical Data in the
Korean Seawaters (suggestion as one of CC test sites)
• FL(0 - ), L w (λ) and E d (λ) data obtained from I-eo-do & new Gageo-cho
(2010 ~) Ocean observing Station
360 o
L wT
L sky
E d
(0 + )

KORDI’s s demand
‣ Service about an offer of MERIS data (past data)
• Date : Jan. 2002 – Dec. 2008
• Area : around the Korean Peninsula
• Sat. Data : MERIS Level-1 & Level-2

KORDI’s s Proposals (III)
‣ MERIS Sat. data Exchange with GOCI
(After launching of GOCI, and if data quality is good)
• GOCI’s Launching Schedule : Nov. 2009
• Data : Level-1B
‣ Proposal for GOCI vicarious calibration &
Validation with MERIS in Korean waters

Thank you