A comparison between the IOCCG Simulated Data Set and NOMAD V2 from an OWT

perspective

Timothy S. Moore

University of New Hampshire

GIOP meeting

Sept. 25, 2010

Anchorage Alaska

OWT NOMAD*

w/ IOPs

IOCCG

Sim.

Global Avg.

1 3 (9) 7 31

2 8 (14) 8 31

3 18 (17) 10 21

4 20 (26) 4 9

5 19 (14) 10 4

6 22 (13) 40 2

7 9 (7) 20 1

8 2 (1) 1 <1

Distribution of OWTs in Data sets vs. Ocean Obsverations (numbers are in percent)

* - AOP without matching IOPSs

N=41N=45

N=180

N=91

N=6N=19

N=45

N=43

OWT 1

OWT 2

OWT 3

OWT 4

OWT 5

OWT 6

OWT 7

OWT 8

ag411

OWT 1

OWT 4

OWT 3

OWT 2

OWT 5

OWT 6

OWT 7

OWT 8

bbp slope

aph

aph 443

Comparison to NOMAD data

IOCCG

OWT 1

NOMAD

ag s

IOCCG

NOMAD

log ag443

OWT 1

log aph443 ag443/at443 bbp slope

log ag443bbp slope

log aph443

OWT 2

IOCCG

NOMAD

-2.5 -2 -1.5 0.5-1 -0.5 0 -2.5 -2 -1.5 -1 -0.5 0 -0.5 0 0.5 1 1.5 3.52.5 32

ag443/at443

OWT 3

log ag443 bbp slopelog aph443

IOCCG

ag443/at443

OWT 4

log ag443 bbp slopelog aph443

IOCCG

ag443/at443

OWT 5

log ag443 bbp slopelog aph443

IOCCG

ag443/at443

OWT 6

log ag443 bbp slopelog aph443

IOCCG

ag443/at443

OWT 7

log ag443 bbp slopelog aph443

IOCCG

ag443/at443

OWT 8

log ag443bbp slope

log aph443

IOCCG

ag443/at443

All

Summary

• There are some inconsistencies in the OWT-based distributions of IOPs between NOMAD and the IOCCG simulated data set.

• Both data sets are skewed towards coastal/case 2 waters.

• Both data sets have some questions regarding the spectral slope of CDOM.

• If a new simulated data set is being considered, the generation of IOPs and IOP pairs could be further constrained by the variance and co-variance as seen in NOMAD within different OWTs.

• In addition, the representation of data points could be guided by the global distribution of naturally occurring OWTs.