East Sea -- Thermal/Bio-Optical Relationships

East Sea -- Thermal/Bio-Optical Relationships

• Define region of interest

• Extract ROI pixels from SST (AVHRR) and chlorophyll (SeaWiFS) imagery - daily scenes and monthly composites

• Examine thermal/bio-optical relationships (scatter plots, image overlays)

• Examine temporal and spatial changes (time-series analysis, histograms)

North Basin

Subpolar Front

South Basin

KoreanCoast

North Basin -- May 21, 1999

CHL

SST

AVHRR and SeaWiFSCollected ~ 6 hrs apart

CHL > 2.0 g/l

SST

CHL > 2.0 g/l Chlo

rophyll

SST

SST Chlo

rophyll

SST

Subpolar Front -- May 21, 1999

CHL

SST

CHL > 2.0 g/l

SST

AVHRR and SeaWiFSCollected ~ 6 hrs apart

Chlo

rophyll

Chlo

rophyll

SST

SST

CHL > 2.0 g/l

South Basin -- May 21, 1999

CHL

SST

CHL > 2.0 g/l

SST

AVHRR and SeaWiFSCollected ~ 6 hrs apart

Chlo

rophyll

Chlo

rophyll

SST

SST

CHL > 2.0 g/l

Korean Coast -- May 21, 1999

CHL SST SST SST

Chlo

rophyll

SST SST SST

CHL > 2.0 g/l

CHL > 2.0 g/l

Subpolar Front -- April, May, June, 1999

April 21, 1999CHL > 2.0 g/l

SST

May 21, 1999

June 9, 1999

CHL > 2.0 g/l

Chlo

rophyll

SST

Chlo

rophyll

SST

Chlo

rophyll

SST

Subpolar Front

Chlorophyll SST4/21/99

8.0 - 10.0

5/21/9911.5 - 13.5

6/09/9914.0 - 16.0

SeaWiFS Monthly Chlorophyll Composite -- April 1999

0 5.0

SeaWiFS Monthly Chlorophyll Composite -- May 1999

0 5.0

SeaWiFS Monthly Chlorophyll Composite -- June 1999

0 5.0

SeaWiFS Chlorophyll Concentration, by Region

1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 70

10

20

30

40

50

60

Chlorophyll (g/l)

1 0.0 - 0.52 0.5 - 1.03 1.0 - 1.54 1.5 - 2.05 2.0 - 2.56 2.5 - 3.07 > 3.0

May 1999

North BasinSubpolar FrontSouth BasinKorean Coast

% T

otal

RO

I A

rea

1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 70

5

10

15

20

25

30

35

8090

100April 1999

Chlorophyll (g/l)

North BasinSubpolar FrontSouth BasinKorean Coast

% T

otal

RO

I A

rea

1 0.0 - 0.52 0.5 - 1.03 1.0 - 1.54 1.5 - 2.05 2.0 - 2.56 2.5 - 3.07 > 3.0

1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 7 1 2 3 4 5 6 70

10

20

30

40

50

60

70

80

90

100

North BasinSubpolar FrontSouth BasinKorean Coast

Chlorophyll (g/l)

June 1999

% T

otal

RO

I A

rea

ROI

1 0.0 - 0.52 0.5 - 1.03 1.0 - 1.54 1.5 - 2.05 2.0 - 2.56 2.5 - 3.07 > 3.0

SeaWiFS Monthly Mean Chlorophyll Concentration, by Region

JFMAMJ JA JFMAMJ JA JFMAMJ JA JFMAMJ JA JFMAMJ JA0.0

0.5

1.0

1.5

2.0

2.5

3.0

Entire BasinNorth BasinSubpolar FrontSouth BasinKorean Coast

Mea

n C

hlor

ophy

ll (

g/l)

ROI

January - August, 1999

Summary

• SST at the front increased ~ 6° over 1.5 month period from late April to early June.

• SST/chlorophyll relationship is complex:- high chlorophyll related to mixing regimes?

- not tied as much to water mass distribution?

• At Subpolar Front, chlorophyll concentration was highest south of front in March and April, north of front in May and June (although concentrations were lower).

• Spatial/Temporal Distributions:April - highest chlorophyll in Korean Coastal and

South Basin; lower at Front and North Basin.

May - Decrease at Korean Coast and South Basin (sharp); no change at Front; highest at North Basin (sharp increase).

June - All areas very low, particularly South Basin; North basin is the highest.