Part I

Oceanographic Observations

NOAA Ship Ronald H Brown

Vocals/Stratus Leg 1 and Leg 2

Leg 1: Charleston, SC Oct 6 – Arica Nov 3 Leg 2: Arica Nov 9 – Arica Dec 2

Leg 1: Charleston, SC Oct 6 – Arica Nov 3 Leg 2: Arica Nov 9 – Arica Dec 2

Sampling in Ecuadorian,

Peruvian, international and

Chilean waters.

Sampling in international

and Chilean waters.

Blue circles – SST drifters

Yellow diamonds – Profiling floats

Underway from Rodman to Arica

with ~2.5 days at WHOI/Stratus

mooring and ~3 days at DART

• Air-sea fluxes, bulk meteorology

• Atmospheric profiling

• Cloud properties, photographs

• Aerosol physics, chemistry, optics

• Recover/deploy WHOI mooring

• Recover/deploy DART mooring

• Underway ocean sampling (T,S, vel)

• Radiosondes

• SST drifters

• Profiling ocean floats (T,S, O)

• Phytoplankton sampling

• Seawater DMS, DMSP, chlorophyll

• Underway PCO2

• Optical absorption spectroscopy

• C and X band radars

• CTD profiles, water sampling

• Ocean vertical microstructure profiles

WHOI Stratus buoy: bulk

meteorology; ocean

temperature, salinity, velocity

time series in upper 1500 m.

Chilean Navy Hydrographic

and Oceanographic Service

(SHOA) DART (tsunami

warning) buoy, fitted with WHOI

bulk meteorological sensors

and ocean T and S sensors in

upper 300 m.

WHOI Stratus buoy 2007

Mean wspd 6.6 m s-1

Mean incoming swr 205.7 W m-2

Mean incoming lwr 371.8 W m-2

Mean sst 20.09°C

Mean at 18.97°C

Chilean Navy Hydrographic

and Oceanographic Service

(SHOA) DART buoy 2007

Mean wspd 5.4 m s-1

Mean incoming swr 178.2 W m-

2 Mean incoming lwr 378.5 W

m-2

WHOI Stratus buoy 2006-2007

Net heat flux 18.1 W m-2

Net swr 194.4 W m-2

Net lwr -45.0 W m-2

Net sensible-10.9 W m-2

Net latent-120.3 W m-2

DART buoy 2006-2007

Net heat flux 27.5 W m-2

Net swr 168.4 W m-2

Net lwr -36.2 W m-2

Net sensible-10.1 W m-2

Net latent-94.7 W m-2

Heat fluxes

at 20˚S

Assess gridded

products and models

with 8 20˚S cruise

sections

7085100

-120

-80

-40

GFDL CM2.1

late

nt

7085100-40

-30

-20

-10

0

sensib

le7085100

-100

-75

-50

-25

0

longw

ave

7085100150

200

250

300

sola

r

70851000

40

80

120

160

net

west longitude

7085100

-120

-80

-40

IROAM

7085100-40

-30

-20

-10

0

7085100-100

-75

-50

-25

0

7085100150

200

250

300

70851000

40

80

120

160

Model

WHOI ORS buoy

OAFlux (1984-2002) analysis

CORE (1984-2004)

NOAA ship observations

VOCALS 2008 20S section

longitude

heig

ht (k

m)

2001

altitude (km)

potential temperature (K)

-85 -80 -750

1

2

290

300

310

specific humidity (g kg-1

)

-85 -80 -750

1

2

0

5

10

2003

altitude (km)

-85 -80 -750

1

2

290

300

310

-85 -80 -750

1

2

0

5

10

2004

altitude (km)

-85 -80 -750

1

2

290

300

310

-85 -80 -750

1

2

0

5

10

2005

altitude (km)

-85 -80 -750

1

2

290

300

310

-85 -80 -750

1

2

0

5

10

2006

altitude (km)

-85 -80 -750

1

2

290

300

310

-85 -80 -750

1

2

0

5

10

longitude

2007

altitude (km)

-85 -80 -750

1

2

290

300

310

longitude

-85 -80 -750

1

2

0

5

10

2001

altitude (km)

potential temperature (K)

-85 -80 -750

1

2

290

300

310

specific humidity (g kg-1

)

-85 -80 -750

1

2

0

5

10

2003

altitude (km)

-85 -80 -750

1

2

290

300

310

-85 -80 -750

1

2

0

5

10

2004

altitude (km)

-85 -80 -750

1

2

290

300

310

-85 -80 -750

1

2

0

5

10

2005

altitude (km)

-85 -80 -750

1

2

290

300

310

-85 -80 -750

1

2

0

5

10

2006

altitude (km)

-85 -80 -750

1

2

290

300

310

-85 -80 -750

1

2

0

5

10

longitude

2007

altitude (km)

-85 -80 -750

1

2

290

300

310

longitude

-85 -80 -750

1

2

0

5

10

PBL height tilted west in 2001, 2005, 2006, 2007;

no tilt in 2003, 2004, 2008.

C-130 85W sections can identify if this is synoptic variability.

specific humidity (g kg-1)potential temperature (K)

Cloud base

10% higher

than LCL

Cloud base

above 900 m

decoupled from

surface layer

Decoupling observed from the ship (2007)

SUMMARY OCEAN MEASUREMENTS VOCALS REX - R.H. BROWN LEG2 (Nov. 9th – Dec 2nd 2008) compiled by Fiamma Straneo (WHOI)

30 CTD (conductivity, temperature, depth) profiles (to 1000-2000m) were collected in eddies, fronts and the boundary current together with oxygen, turbidity and fluorometer pofiles. Water samples were collected for nutrients, chlorophyll and dimethylsulfide by C. Grados (IMARPE), B. Huebert (U. Hawaii), A. Hind and P. Matrai (Bigelow).

300 Underway CTD profiles (to 300-700m) were collected to map the large-scale, mesoscale and submesoscale structure of the upper ocean

4 Surface Drifters and 4 Profiling SOLO floats were deployed in the center of eddies or in frontal regions to provide long-term context to the VOCALS-Rex measurements.

15 VMP (vertical microstructure profiles) were collected to quantify mixing rates in the range of oceanic environments of the SEP (center and edges of mesoscale cyclones and anticyclones, the offshore region and the coastal upwelling region)

Underway data (velocity, temperature, salinity, fluorometer) was collected along the way throughout Leg 2.

SUMMARY of LEG 2 Ocean Measurements

C1

C2C3

A3

A2

Figure: Brown’s trajectory (black) and underway CTD sections (white dash)CTD stations (blue circles), VMP and CTD (blue with red rim),

24 hour monitoring stations (green circles – red rim), float and drifter deployments (white squares and circles).

Background field is SST for November 18th. Contours show

sea-surface height (contour interval 5 cm; positive red and negative blue).

Profiling Float Deployed from R.Brown (photo F. Straneo)

Vertical MicrostructureProfile (photo F. Straneo)

Property Profiles

Eddy-blue, mean-

black

eddy

eddy

3 Cyclonic eddies (C1, C2 and C3)were sampled in Leg 2

Characteristics- cold SST anomaly- shallow mixed layer- sub-surface warm, salty core (300m)

Preliminary Results 1: Characteristics of the Cyclonic Eddies

Preliminary Results 2: Coastal Upwelling Region and source of Eddies:Figure shows an underway CTD section up to the coast of Chile.

Upwelling of fresh and coldwaters of Subpolar origin to the surface

Cyclonic Eddy with a warm salty sub-surfacecore

Boundary currentwith same propertiesAs the eddies’ core

Preliminary Results 3: Sea water DMS (dimethylsulfide) was elevatedaround the edges of the cyclonic eddies likely due to the entrainmentof nutrients into the mixed layer – these regions also had more elevatedvalues of atmospheric DMS and, thus, play a role in offshore aerosol production

Sea water DMS variations are correlated with the upperocean’s temperature andsalinity variations.

The VOCALS-Peru Cruise ExperimentRV Jose Olaya Cr. 2008-10

The VOCALS-Peru Team

II. WORK PACKAGES

WP 1 – Atmosphere: Coastal Wind Jet Structure and Cloud Clearing

WP 2 – Physical and Biogeochemical characteristics of the upwelling cell(plume and front)

WP 3 – Biological properties: Community structures, interface fluxes and Fishdistribution

WP 4 – Ocean/atmosphere interactions and biological response

H1 - There is a strong feedback/interaction between the variability of the

atmospheric coastal wind, the upwelling cell and the associated

thermic front and cloud clearing between Pisco and San Juan.

H2 - There is a strong interaction between oceanic physical structures and

biogeochemical/fish community structures and distribution.

I. HYPOTHESES

! Specific 15-day cruise (atmospheric, hydrographic, biogeochemical and

fishery acoustics observations, glider and zooplankton experiments),

! Satellite and historical (1960-2007) in situ data

! Coupled Model platform: Atmosphere (WRF, MM5), physics (ROMS),

Biogeochemistry (PISCES, SEAPODYM)

III. TOOLS

Data setsData Instrument/sensor

Spatial/Vertical

resolutionAcquisition rate

Data/Samples

collected

Underway data

Winds, Rel Humidity, Ta, SLP Vaisalla Met. Shipboard Station 1 min interval

Currents VM-ADCP RDI-mod.OS-75 04-16 m, 0-600/700 m 3 sec 2.5 Gbytes

T , S , O 2 , Fluorescence, Turbidity Slocum-type glider 0-200m, Vert. vel.: 10cm/s LR/3m, HR/1 m

SST (°C), currents Surface drifters WOCE-SVP type

T (°), S (PSU) EDAS System 20 min interval

pCO2 (ppm) LICOR mod 6262 2sec/10 min average

Fish abundance and distribution SIMRAD EK-60 echosounder 0-500 m, 38/120/200 kHz. 1 nm (UBM) 2040 nm

On station - sensors

Ta, Winds, Rel.Humidity, SLP GAUSS System- NCAR 132 launchings

Conductivity, Temperature, Depth CTD SBE911+ 0-1000 m 24 measurement/sec 113 profiles

Fluorescence Chelsea UV Acquatracka (SN088-235) 0-1000 m (/6000m) 24 measurement/sec 113 profiles

Oxygen SBE-43 (S/N1342)-IRD 0-1000 m 24 measurement/sec 113 profiles

On station - samples

Oxygen concentrations Winkler method Standard depths (0-500m) 401 samples

Nitrates, Nitrites, Phosphates, Silicates UV Vis Spectrometer Lambda45 P Elmer Standard depths (0-500m) 401 samples

PH Metler Toledo mod. Multiseven Standard depths (0-500m) 375 samples

Chlorophyll-a Turner Design 10AU fluorometer Standard depths (0-75m) 260 samples

Phytoplankton Cualitative analysis Standard net 0m 37 samples

Phytoplankton Quantitative analysis Niskin bottles Standard depths (0-75m) 153 samples

Zooplankton Cualitative analysis WP-2 0m 35 samples

Zooplankton vertical distribution Hensen net 0-50m 17 samples

Anchovy eggs CUFES 0m 20min interval. 313 samples

Larvae collection/Zooplankton distrib. Bongo net 0-300m 16 samples

Observations of oceanic currents

structures off Southern PeruGérard ELDIN (LEGOS, Toulouse, France)

Thanks to Carmen GRADOS and the scientific party

onboard R/V José Olaya

Data for this presentation were obtained

during the VOCALS-REx cruise of R/V

José Olaya: 03-17 October 2008

• RDI 0S-75 VM-ADCP

• 8 m bins, 10 mn averages, ~16-600 m

• CODAS3 processing software and data

base

Selected ADCP sectionsPeru-Chile Under-Current (PCUC)

Callao

ParacasPisco

San Juan

Cerro Azul

Ica

Summary

• The Peru Current and Peru-Chile Under-Current (PCUC) werethe dominant features of the circulation during VOCALS-REx.

• Strong spatial/temporal variability in PCUC transport and core

location were observed. Model results reproduced such a

variability, even at moderate resolution:

• Strong small scale variability was noted in the surface layer.

• Surface flow was mostly southward and partly non-geostrophic.

Whether that flow formed an independent Peru-Chile Counter-Current,

or was an upward extension of the PCUC is underl investigation.

50-300m, 5-y avg, from a ROMS run,

(J. Boucharel)