CIOSS Ocean Optics

Aug 2005

Ocean Optics, Cal/Val Plans, CDR Records for

Ocean Color

Ricardo M LetelierOregon State University

Outline

- Defining Ocean Color products and their use

- Cal/Val issues with special emphasis in coastal environments

- Developing NOAA’s capability for ocean color CDRs Outcome of our first workshop

CIOSS Ocean Optics

Aug 2005

HES-CW Threshold & Goal Channels and their Applications

CIOSS Ocean Optics

Aug 2005

Uses for Ocean Color Products • Near real-time observations over regional

scales - for short term forecasting (i.e. human and ecosystem health, navigation hazards) - to study ecosystem response to physical

forcings (i.e. nat. res. management)

• Long term time-series to characterize seasonal, inter-annual and decadal changes (landscape change, ecosystem climate response)

CIOSS Ocean Optics

Aug 2005

From Gregg et al. 2005:

-Looking at interannual variability in global annual chlorophyll distribution

4% global increase

- Changes are not uniform Increases in coastal areas

-Trend is different that previously observed previously between the 80s and 90s

From Behrenfeld (unpublished)

CIOSS Ocean Optics

Aug 2005

CIOSS Ocean Optics

Aug 2005

CIOSS Ocean Optics

Aug 2005

nLw consistency & In Situ VerificationField Validation: Lwn’s

Temporal Consistency

From NASA / Ocean Color Processing Group

* Lwn: Normalized Water-leaving Radiance

CIOSS Ocean Optics

Aug 2005

From nLw to ocean color products Reflectance spectrum as a

function of [chl a]

COAS-OSU Direct Broadcast

1 CIOSS postdoc worked on the processing of the Oregon Coast optics and SeaWiFS/MODIS match-up data (2003-2004)

CIOSS Ocean Optics

Aug 2005

chlFLH empirical(this study)

MODIS chla_2In situ chl

GLOBEC NEP AUGUST 2002

CIOSS Ocean Optics

Aug 2005

CIOSS Ocean Optics

Aug 2005

Inverse bio-optics approach using the merging of concurrent remote sensing datasets

From Maritorena & Siegel (2005)

SeaWiFSMODIS Terra/Aqua

In situ Bio-optics

In situ discretesamples

Oregon Datasets

CIOSS Ocean Optics

Aug 2005

Developing long term Ocean Color Products

CIOSS Ocean Optics

Aug 2005

A Consistent Ocean Color Time Series Requires Similar:

• Calibration• Algorithms• Spatial and Temporal Resolution (Level-

3)• Data Format• Access• Analysis Tools• Quantification of errors and biases

CIOSS Ocean Optics

Aug 2005

Information FlowL1A data

Navigate, calibrate (vicarious) L2 algorithms (input ancillary fields of humidity,

ozone, wind speed, surface pressure) Binning in space and time L3 fields

• Satellite/sensor information appended to L1A – Issues regarding preserving geometry, etc. for

VIIRS– Differences between “level” world and IPO

definitions of RDR, SDR, EDR, etc.

CIOSS Ocean Optics

Aug 2005

Climate Data Records

• Chlorophyll (global) as Thematic Climate Data Record (TCDR)– May be others in the future as

knowledge improves

• nLw as Fundamental Climate Data Record (FCDR)– We require saving these at full

resolution of sensor– Assumes that Level 1A data are

preserved

CIOSS Ocean Optics

Aug 2005

Chlorophyll as TCDR• Ensuring consistency across multiple platforms

– Challenging in NPOESS era given launch-on-failure strategy• Sensor overlap greatly facilitates creation of consistent data records

• Sensor pre-launch & on-orbit characterization– Looking at the Moon– Need access to solar diffuser data

• Defining resolution scales• In situ data

– Vicarious calibration– Validation

• Intercalibration of in situ sensors– Need more than one sites?

• Archive services– Documentation– Data access and Formats

• Processing & reprocessing– Need science-focused processing system

CIOSS Ocean Optics

Aug 2005

Normalized Water-leaving Radiances (nLw) as FCDR

• Ancillary data fields– Documentation on models– Versions of fields– Current version of vicarious calibration– Ocean Color Project experience

• Ensembles of tables, input fields, etc.

• Validation– Need SeaBASS-like system for in situ

data

CIOSS Ocean Optics

Aug 2005

Roles and Responsibilities

• There is a continuing need for NASA involvement, given its extensive experience in ocean color and its focus on scientific research

• NOAA needs to begin to develop its own capacity to produce CDRs

• Next step will be a workshop focusing on the end-to-end processes needed to meet the science requirements for ocean color CDRs– Workshop will be held on the East Coast to

ensure involvement from NASA and NOAA

CIOSS Ocean Optics

Aug 2005

CIOSS Ocean Optics

Aug 2005