IOCCG-23 meeting at Rome, Italy, March 6-8, 2018

Prakash Chauhan

Space Applications Centre, Indian Space Research Organisation

Ahmedabad-380015, INDIA

ISRO REPORT ON OCEAN COLOUR ACTIVITIES

1

OCEANSAT-2 OCM Jan 31, 2018Natural Colour Composite

Ganga-Brahmaputra River Delta, Bay of Bengal

IOCCG-23 meeting at Rome, Italy, March 6-8, 2018

Update on Ocean Colour Activities in India

OCEAN COLOUR OPERATIONAL DATA PRODUCTS & DISSEMINATION FOR OCM-2

Retrieval algorithms for Ocean colour parameters over case-2 waters, coastal and inland waters

Inversion algorithms for quantifying absorption and backscattering process (IOP estimation)

In-situ database on AOP, IOP and in-water constituent concentrations for seas around India

India organised SAFARI-2 conference at Kochi during Jan 15-17, 2018.

AVIRIS-NG Airborne Hyperspectral data for Coastal / Inland waters

More than 74 sites in India were covered by AVIRIS-NG airborne campaign, including 5 sites for

coastal, inland waters and coral reefs

• Hyperspectral data is being analysed for algorithm development and retrieval of waters

colour parameters

• AVIRIS-NG Phase II is under progress. Overflights for 11 sites are planned in Phase II.

OCEANSAT-3 OCM sensor development

OCEANSAT-3 satellite is planned in later half of 2018. It will carry a

Ocean Colour Instrument, Sea Surface Temperature Monitor (SSTM),

Ku band Scatterometer and ARGOS system of CNES.

OCM-3 sensor having 13 bands and a SST sensor is currently under

development at ISRO.

2

OCM

SSTM

SCAT

OCEAN COLOUR DATA PRODUCTS FROM OCM-2

• Improved atmospheric correction in turbid waters and coastal waters

• Improved estimates of chlorophyll concentration using non-linear

optimization techniques

• Estimation of CDOM absorption using regional datasets.

• In-situ database on AOP, IOP and in-water constituent concentrations for

seas around India

CDOM absorption (443) from Oceansat-2, OCM (8 March, 2017) using new regional algorithm

Chlorophyll concentration in coastal waters Off Gujarat from OCM2 (1 April, 2017)

Improved atmospheric correction and chlorophyll estimation from OCM2( 27 December , 2015)

Bad

retrieval

(Negative

values)

Trichodesmium Bloom detection using OCEANSAT-2 OCM data on

May 3, 2017 Off Ratnagiri coast, Maharashtra, India

Trichodesmium

Greenwaters

Ratnagiri

Mumbai

Field Photos taken duringSagar Sampda Cruise

Field Photo Ratnagiri

Trichodesmium

OCEANSAT-2 OCM dataMay 3, 2017

Trichodesmium spp. is nitrogen fixing marine blue-green algae commonly

found in tropical oceans. They form massive blooms during summer period,

when surface waters are warm and devoid of nitrate. These blooms are

important for nitrogen bio-geo-chemistry of oceans.

Arabian Sea

May 11, 2017

Massive Outbreak of Noctiluca algal blooms in the Arabian Sea as captured by Indian OCEANSAT-2 OCM on Feb 8, 2018

Arabian Sea

Every year during winters

north-western Arabian

Sea experiences

outbreak of Noctiluca

algal blooms. This bloom

at times causes fish

mortality on Oman coast

due to hypoxia.

This image is captured by

Indian OCM sensor on

OCEANSAT-2 satellite on

Feb 8, 2018.

Field Photo

Noctiluca cells

Water in flask

Noctiluca colonyAlgal bloom

ISRO-NASA Joint Campaign on AVIRIS-NG Airborne Hyperspectral data

for Coastal / Inland waters

• The second phase started from 19th February. 52 sites in India will be

covered by AVIRIS-NG airborne campaign, including 11 sites for coastal,

inland waters and coral reefs

• Hyperspectral data analysis of first phase carried out for selected areas.

0

1

2

3

4

375 475 575

CDOM Absorption Coefficient from AVIRIS-NG data

Wavelength (nm)

CD

OM

Ab

sorp

tio

n C

oe

ff(m

-1)

Radiance Image of Band No-56 (Red)before atmospheric correction

Radiance Spectra

Reflectance Image after atmospheric correction

Reflectance Spectra

0

0.01

0.02

0.03

0.35 0.55 0.75 0.95

%error = 16%

0

0.01

0.02

0.03

0.35 0.55 0.75 0.95

Rrs: Aviris :In-situ

%error = 37%

High resolution CARTO-2E (2m) data for Coastal Pollution dumps and Point Source discharge in Mumbai region

Mumbai

IOCCG-23 meeting at Rome, Italy, March 6-8, 201820 21 22 23 24 25 26 27 28 29

Temp [°C]

-140

-130

-120

-110

-90

-80

-70

-60

-40

-30

-20

-10

-150

-100

-50

0

Dep

th [

m]

0.00 0.04 0.08 0.12 Chl-a [ug/L]

0.00 0.02 0.04 Rrs [/sr]

0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 kEd [/m]

0.0E+0 2.0E-3 4.0E-3 Lu [uW/cm^2/nm/sr]

Nov 15, 2002 [1130IST]65°58.326E/ 13°03.558S

Temp

Chl-a

kEd412

kEd443

kEd490

Rrs443

Rrs490

Rrs555

Lu670

In-situ Bio-Optical data collection

•Radiometric measurements

•Spectrophotometeric measurements

•HPLC

•Fluorometry

•CTD

•Microscopy

•Nutrients

•pH

•DO

•Ancilliary data

•Aerosol optical depth

•C13 and N15 Measurements

•POC & DOC

In-situ data collection in collaboration with other

National Institutes and Universities.

Measurement & Analysis according to Ocean Optics

Protocols

0

0.5

1

1.5

2

2.5

3

3.5

800

769.0

0,

738.0

0,

707.0

0,

676.0

0,

645.0

0,

614.0

0,

583.0

0,

552.0

0,

521.0

0,

490.0

0,

459.0

0,

428.0

0,

397.0

0,

366.0

0,

335.0

0,

304.0

0,

273.0

0,

wavelength

ab

s m

-1

0 m 10m 20 m

7

Calibration-Validation Plans for Oceansat Missions

OCM-2, 3 vicarious calibration using

Kavaratti Cal-Val site

2009 - 2015

OCM2

BandVC-gain

coefficient

1 0.95

2 1.02

3 0.95

4 0.96

5 0.92

6 0.89

7 0.89

8 0.81

OCM-III proposed Cal-Val activities

Rann of Kutchchh desert site

for vicarious calibration of

OCM-3

1

2

54

78

9

63

10

11

12

13

141

5

Location of Instruments

1 – Radar tide gauge

2 – SeaPRISM

3 – Micro met tower

4 – Global radiation budget

5 – Rain gauge

6 – IR thermometer

7 – wave rider buoy

8 – ACS, AC-9

9 – bottom pressure recorder

10 – Bio-optical buoy

11 – Satellite transmitter

12 – Robotic above water

hyper-spectral radiometer

13 – Aerosol sampler

14 – solar panel

15 – steps

16 – Conductivity sensor

17 – Current meter

18 – PH sensor

19 – Chlorophyll sensor

• A permanent observational platform in case-2 waters off

Veraval for measurement of bio-optical, physical chemical &

atmospheric parameters.

• Regular sea-truth campaign for validation of products

• Radiosonde and Buoy observations for validation of SSTM

IOCCG-23 meeting at Rome, Italy, March 6-8, 2018

Future EO Satellites for Ocean Observation

OCEANSAT-3Global Ocean Coverage

Payloads

• 13 Band Ocean Colour Monitor

• 2 Bands for SST

• Ku Band Scatterometer

Status

• PSLV Launch 2018-19

OCEANSAT-1 OCEANSAT-2 RISAT-1 SARAL INSAT-3D OCEANSAT-3 INSAT-3DR GISAT

GISAT

Continuity of space observations…..

Ocean

&

Atm

osphere

1999 2009 2018

2018-19

9

IOCCG-23 meeting at Rome, Italy, March 6-8, 2018

Oceansat-3 OCM Instrument

• Oceansat OCM 3 for assured continuity

• 13 Channels in 400-1010 nm range incomparison

• 2 Channels around 11 and 12 μm forSea Surface Temperature

• Bandwidth 10 nm or lower.

• Polar Sun Synchronous Global Mission

• Local Area Coverage at 360m andGlobal Area coverage at 1 Km

• Complete Globe coverage in 2 days

Band No.

λc

(nm)Application Potential

B1 412 Yellow Substance Absorption

B2 443 Low Chlorophyll-a concentration

B3 490 Moderate Chlorophyll –a concentration

B4 510 High Chlorophyll –a concentration

B5 555 Chlorophyll-a reference band

B6 566 Trichodesmium bloom (Phycoerythrinpigment) detection for nitrogen cycle

B7 620 Algal bloom detection and Sedimentconcentration

B8 670 First Baseline for Chlorophyll Fluorescence

B9 681 Chlorophyll Fluorescence detection

B10 710 Second baseline for Chlorophyll fluorescence

B11 780 Atmospheric correction; avoids O2 absorptionband

B12 870 Atm. Correction. Good separation fromprevious bands. Better for coastal waters

B13 1010 Atm. Correction. over for coastal waters

SST bandsB14 11250 Sea surface temperature detection

B15 12250 Sea Surface Temperature detection

Ocean Colour Bands

Old bands New bands

Payload development is in progress for OCEANSAT-3

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IOCCG-23 meeting at Rome, Italy, March 6-8, 2018

Thank You 11