Oceanic Remote Chemical/optical Analyzer (ORCA)

An autonomous profiler monitoring water quality in south Puget Sound

T,S, O2

NO3,

ORCA overall;Steven Emerson; Allan Devol

Jan Newton; Rick Reynolds

PRISM John Dunne; Wendi Ruef

General Support

Nutrient Analyzer

• Develop a robust remote chemical and biological monitoring system

• T, S, Light, Meteorology

• NO3, O2, Chl-a, turbidity

• NH4, Gas Exchange parameters

• Telemeter data back to UW

• Monitor the spectrum of time-scales

• Hourly (tides), Daily (solar), Weekly (plankton growth), Monthly (blooms), Annual (seasons, and inter-annual, e.g., El Nino)

• Describe natural variability and characterize and help evaluate potential human influence

• Validate PRISM physical and biological models

• Ground-truth satellite ocean color

ORCA GOALS

WHAT DOES ORCA LOOK LIKE?

light

solar panel

radarreflector

superstructure

Platform and housing For Winch, electronics, etc

Atlas float(cut awayview)

ballast ring

anchoring(break inscale)

pack

age

weather station

ORCA Schematic View

4.2 m

solar panel

WHERE IS ORCA?

Photosynthesis (P) : [O2]CO2 + H2O + nutrients CH2O + O2

Respiration and Decay (R) : [O2]CH2O + O2 CO2 + H2O + nutrients

Excess nutrients and stratification (eutrophication) can lead to consumption of all the oxygen in a system, so fish can no longer survive there

NutrientsSt

ratif

icat

ion

http://www.ocean.washington.edu/research/orca/

July 12 - 28, 2000

enhancement

October 15-21, 2000Sept. 20- Oct. 2, 2000

no enhancement surface enhancement

Sigma-t

Chl ug/l

O2 mg/l

enhancement no enhancement surface enhancement

0

5

10

15

0 500 10000

5

10

15

20

25

0 500 10000

5

10

15

0 200 400 600

12 Oct 0025 Sep 0010 Jul 00

dept

h (m

)

primary productivity (mg C m-3 d-1)

Effect of nutrient addition on phytoplankton productivityblue = ambient productionred = spiked with NH4 and PO4

Carr Inlet, WA Ecology

Goals for 2003

• Science Goals:

• MIXED experiment (April 2003)

• Nutrients; NO3 and NH4

• Move Orca for Brightwater

• Publish Orca Results

• Prism Goals:

• Use Orca to Validate ABC-POM

• Carr Inlet

• Brighwater site

• Outreach

• Maintain Orca Website

• Orca School

Longer Term Goals

• Science

• Study Bloom Dynamics/gas exchange/nutirent/physics coupling

• Mixed layer

• Aphotic zone

• Add Sensors (PO4, Eddy Correlation, micro-gradient)

• Publish Orca Results

• Expand Network:

• South Sound, Main Basin, Hood Canal, Admiralty Inlet

• Continue and Expand Outreach/Education