Southwest Pacific Ocean Circulation

and Climate Experiment (SPICE)—

Part II. Implementation Plan

A. Ganachaud1,2, G. Brassington3, W. Kessler2, C.R. Mechoso4,

S. Wijffels5, K. Ridgway5, W. Cai5, N. Holbrook6,7, P. Sutton8,

M. Bowen8, B. Qiu9, A. Timmermann9

, D. Roemmich10,

J. Sprintall10, D. Neelin4, B. Lintner4, H. Diamond11,

S. Cravatte1

, L. Gourdeau1, P. Eastwood12, T. Aung13

1Laboratoire d’Etudes en Géophysique et Océanographie Spatiales (LEGOS)/Institut de

Recherche pour le Développement (IRD), Toulouse, FRANCE/Nouméa, NEW CALEDONIA

2National Oceanic and Atmospheric Administration (NOAA)/Pacific Marine Environmental

Laboratory (PMEL), Seattle, WA, USA

3Centre for Australian Weather and Climate Research, A partnership between the Australian

Bureau of Meteorology and CSIRO, Melbourne, AUSTRALIA

4Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, CA,

USA

5CSIRO Marine and Atmospheric Research, Hobart/Aspendale, AUSTRALIA

6School of Geography and Environmental Studies, University of Tasmania, Hobart, AUSTRALIA

7Centre for Marine Science, University of Tasmania, Hobart, AUSTRALIA

8NIWA, Wellington, NEW ZEALAND

9University of Hawaii, Honolulu, HI, USA

10Scripps Institution of Oceanography, San Diego, USA

11NOAA/NCDC, Silver Spring, Maryland, USA

12PI-GOOS/SOPAC, Suva, Fiji Islands

13University of the South Pacific, Suva, Fiji Islands

CLIVAR Publication Series No. 133

NOAA OAR Special Report

October 2008
NOTICE from NOAA

Mention of a commercial company or product does not constitute an endorsement by

NOAA/OAR. Use of information from this publication concerning proprietary products or the

tests of such products for publicity or advertising purposes is not authorized. Any opinions,

findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Oceanic and Atmospheric Administration.

This report should be cited as:

Ganachaud, A., G. Brassington, W. Kessler, C.R. Mechoso, S. Wijffels, K. Ridgway, W. Cai, N.

Holbrook, P. Sutton, M. Bowen, B. Qiu, A. Timmermann, D. Roemmich, J. Sprintall, D. Neelin,

B. Lintner, H. Diamond, S. Cravatte, L. Gourdeau, P. Eastwood, and T. Aung (2008): Southwest

Pacific Ocean Circulation and Climate Experiment (SPICE)—Part II. Implementation Plan.

International CLIVAR Project Office, CLIVAR Publication Series No. 133, NOAA OAR Special

Report, NOAA/OAR/PMEL, Seattle, WA, 36 pp.

Contact: http://www.clivar.org/organization/pacific/pacific_SPICE.php, Alexandre

Ganachaud, Institut de Recherche pour le Développement, BP A5, 98848 Noumea, New Caledonia, Alexandre.Ganachaud@noumea.ird.nc

Contribution No. 3164 from NOAA/Pacific Marine Environmental Laboratory

Also available from the National Technical Information Service (NTIS)

(www.ntis.gov)

ii
LEGOS—Laboratoire d’Etudes en Géophysique

et Océanographie Spatiales

(www.legos.obs-mip.fr), Institut de

Recherche pour le Développement

(www.ird.fr), Toulouse, France/Nouméa, New

Caledonia (www.ird.nc)

NAT OI NAL OCEANIC AND ATMOSPHERIC ADMINISTRAT OI N

U.S. DEPARTMENT OF COMMERCE

NOAA/PMEL—National Oceanic and

Atmospheric Administration/Pacific

Environmental Laboratory, Seattle, WA, USA

(www.pmel.noaa.gov)

Centre for Australian Weather and Climate

Research, CSIRO/Bureau of Meteorology (BOM)

(www.cawcr.gov.au/)

UCLA/AOS—Department of Atmospheric and

Oceanic Sciences, University of California Los

Angeles, Los Angeles, CA, USA

(www.atmos.ucla.edu/)

CSIRO/CMAR—Commonwealth Scientific and

Industrial Research Organization/ CSIRO

Marine and Atmospheric Research,

Hobart/Aspendale, Australia

(www.cmar.csiro.au)

School of Geography and Environmental

Sciences/Centre for Marine Science, University

of Tasmania, Hobart, Australia (http:

//fcms.its.utas.edu.au/scieng/geog/)

IPRC—International Pacific Research Center,

School of Ocean and Earth Science and

Technology, University of Hawaii, Honolulu, HI,

USA (iprc.soest.hawaii.edu)

NIWA—National Institute of Water and

Atmospheric Research, Wellington, New

Zealand (www.niwascience.co.nz/ncco)

SOEST—School of Ocean and Earth Science

and Technology, University of Hawaii,

Honolulu, HI, USA

(www.soest.hawaii.edu/oceanography/)

SIO—Scripps Institution of Oceanography, San

Diego, CA, USA (sio.ucsd.edu)

NAT OI NAL OCEANIC AND ATMOSPHERIC ADMINISTRAT OI N

U.S. DEPARTMENT OF COMMERCE

National Climatic Data Center NOAA/NCDC—Silver Spring, MD, USA

(www.ncdc.noaa.gov/oa/ncdc.html)

PI-GOOS/SOPAC—Pacific Island Global Ocean

Observing System, SOPAC, Suva, Fiji Islands

(www.sopac.org/tiki-index.php?page=

Pacific+Island+Global+Ocean+Observing+

System+PI+GOOSl)

USP—University of the South Pacific, Suva, Fiji

(www.usp.ac.fj)

iii

Contents

1 Introduction 1

2 SPICE Objectives, Benefits, and Legacy 2

3 Overall Organization and Timetable 3

4 Modeling Strategy 5

4.1 Modeling Challenges . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4.2 Modeling Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.3 Modeling Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.4 Numerical Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.5 Data-Model Intercomparison . . . . . . . . . . . . . . . . . . . . . . 13

4.6 Sharing Model Output . . . . . . . . . . . . . . . . . . . . . . . . . . 13

4.7 Current and Proposed Regional Modeling Projects . . . . . . . . . 13

5 In Situ Observations 15

5.1 Observational Challenges . . . . . . . . . . . . . . . . . . . . . . . . 15

5.2 Observational Objectives . . . . . . . . . . . . . . . . . . . . . . . . . 17

5.3 Observational Approach . . . . . . . . . . . . . . . . . . . . . . . . . 17

5.3.1 Large-scale operations . . . . . . . . . . . . . . . . . . . . . 18

5.3.2 Regional scale operations . . . . . . . . . . . . . . . . . . . . 22

5.4 Proposed Observations and Infrastructure . . . . . . . . . . . . . . 22

5.5 SPICE-Related Observational Projects . . . . . . . . . . . . . . . . . 25

6 Data Management and Availability 27

7 Applications and Training 27

8 SPICE Legacy 28

9 References 29

10 Glossary of Acronyms (for Parts I and II) 33

v

Section 1. Introduction 1

1. Introduction

S

outh Pacific thermocline waters are transported in the westward-flowing South Equatorial Current from the subtropical gyre center toward the

southwestern Pacific Ocean—a major circulation pathway that redistributes water from the subtropics to the equator and to the Southern Ocean. The

transit in the Coral Sea is potentially of great importance to tropical climate

prediction because changes in either the temperature or the amount of water

arriving at the equator have the capability to modulate El Niño-Southern Oscillation (ENSO) cycle and thereby produce basin-scale climate feedbacks. The

southern fate of thermocline waters is, comparably, of major influence on Australia and New Zealand’s climate; its seasonal and interannual evolution influences air-sea heat flux and atmospheric conditions, and it participates in the

combined South Indian and Pacific Ocean “supergyre.” Substantial changes

in this circulation have been observed over the past 50 years and continue in

global climate projections. The subtropical gyre has been spinning up in recent

years with possible consequences for ENSO modulation and for the East Australian Current (EAC), whose influence has moved south, dramatically affecting

the climate and biodiversity of Tasmania.

Despite its apparent importance to the climate system, few observations

are available to diagnose the processes and pathways of transport through the

complicated geography of the southwest Pacific. The South Pacific Convergence Zone is poorly documented; the region is remote, and the large temporal variability and strong narrow currents in complex bathymetry pose serious challenges to an observing system. Numerical model results are sensitive

to parameter choices and forcing, and the results are uncertain because of the

lack of in situ data for validation. The existing observational network (Argo,

VOS XBT sampling, and satellite winds and altimetry) is beginning to provide a

large-scale picture, but the complex circulation and western boundary currents

require further dedicated study.

A first report (Ganachaud et al., 2007) lays out the scientific background

and identifies the open issues in the southwest Pacific Ocean. The present

document describes a proposed implementation for an international, regionally coordinated experiment, the Southwest PacIfic Ocean Circulation and Climate Experiment (SPICE). The plan integrates both observational and modeling analysis, and we put forward an overall coordination strategy and an incentive to develop specific collaborative projects to address SPICE issues.
2 Ganachaud et al.—SPICE, Part II. Implementation Plan

2. SPICE Objectives, Benefits,

and Legacy

The goal of SPICE is to observe, simulate, and understand the role of the

southwest Pacific Ocean circulation in (a) the large-scale, low-frequency

modulation of climate from the Tasman Sea to the equator, and (b) the

generation of local climate signatures whose diagnosis will aid regional sustainable development. This goal will be realized through four specific efforts,

which are discussed in detail in the SPICE Scientific Background document

(Ganachaud et al., 2007a):

1. Analysis of the southwest Pacific role in global coupled models;

2. Development of an observational program to survey air-sea fluxes and

currents in the Coral, Solomon, and Tasman Seas, and their inflows and

outflows, with special attention to the strong boundary currents and jets;

3. Combination of these observations with focused modeling efforts to devise a sustained monitoring program to adequately sample the time variability of the currents and their heat and mass transports;

4. Using remotely and locally sampled meteorological fields, and the ocean

analysis, determination of the air-sea heat and freshwater fluxes and water mass transformations that occur in the region, and their effects on

the local and global climate. A focus here may be the design of a process

study to observe, model, and understand the South Pacific Convergence

Zone.

These objectives were established to serve primarily CLIVAR objective 1

(“describe and understand the physical processes responsible for climate variability and predictability on seasonal, interannual, decadal, and centennial

timescales, through the collection and analysis of observations and the development and application of models of the coupled climate system in cooperation with other relevant climate research and observing programmes”). SPICE

objective 1 will help identify key features (e.g., SPCZ, meridional oceanic heat

transports), and their impacts in global climate simulations on seasonal and

decadal timescales. SPICE objectives 2 and 3 are to understand the relevant

air-sea fluxes and oceanic currents, and to design a sustained observing system

that will help improve climate modeling and ultimately prediction (seasonal

prediction of local climate; decadal prediction of the large-scale climate, including ENSO). SPICE objective 4 embraces the transition into operational benefits through local oceanic impacts on the environment (downscaling). This

includes local sea surface temperature (impacts on coral reefs; coastal/island
Section 3. Overall Organization and Timetable 3

climate and cyclone trajectories), sea level rise and its predictability, and capacity building (Pacific Island countries training for specific applications).

SPICE is purposely oriented toward appropriate long-term monitoring to

serve climate prediction, and to foster projects and collaborations with other

fields such as ocean and weather prediction, coral and ecosystem monitoring,

and climate-related diseases. The expected SPICE legacy will be a monitoring system for climate-important quantities, operational tools for local applications along with training and appropriate data accessibility, and more generally a better understanding of (1) local climate impacts and predictability, (2)

fundamental climate processes involved in subtropical-tropical exchanges and

western boundary current variability, and (3) SPCZ dynamics.

3. Overall Organization and

Timetable

S

PICE is regionally focused, but integrates basin-scale studies of the

ocean-atmosphere system. The large-scale context, including the basin

scale South Pacific circulation and its connection with equatorial processes and climate variability, is addressed within CLIVAR and related projects.

The priorities that are specific to SPICE were set as follows (Fig. 1):

1. South Pacific Convergence Zone: formation, variability, air-sea interactions;

2. South Equatorial Current inflow: jet formation, bifurcation on Australia,

western boundary currents;

3. Tasman Sea circulation: EAC/EAUC variability; heat balance and air-sea

fluxes in the Tasman Sea;

4. Gulf of Papua and Solomon Sea circulation: western boundary current

and interior pathways, flow through the Solomon Straits;

5. Downscaling and environmental impacts of climate and oceanic environment changes: cyclones; sea level rise; coral reef sustainability; coastal

ecosystems.

The proposed approach is collaborative and cost-effective, based on existing human and technical resources, and fits within timetabled southwest Pacific activities (Fig. 2). The plan will rely heavily on ocean and atmosphere

modeling that will be combined with three types of observations: (1) process

studies to acquire basic knowledge in the north Coral Sea region, (2) monitoring where necessary, and (3) regional adaptation of global observing programs.

The following two sections describe the modeling and observational issues and

approach.
4 Ganachaud et al.—SPICE, Part II. Implementation Plan

S P C Z

SPICE 

North Coral Sea: issues

WBC and Straits

Thermocline 

water

formation

Link to the Equator and ENSO modulation

SEC inflow:

Jets and Bifurcation

Heat transports

EAC/EAUC:

Variability and air-sea fluxes

Local and regional

oceanic impacts

Figure 1: Main issues addressed within SPICE. Thermocline water formation and junction to the Equator are

addressed within larger-scale programs.

2004 2005 2006 2007 2008 2009 2010 2011 2012

PROGRAM

PLANNING

NUMERICAL

MODELING

OBSERVATIONS

MONITORING

SYSTEM 

DESIGN

FORMULATION OF 

SCIENTIFIC ISSUES

OBSERVATIONAL

PROGRAM DESIGN

SUBMISSION TO

NATIONAL AGENCIES

DEVELOPMENT OF NESTED REGIONAL MODELS

PRELIMINARY HYDROGRAPHIC CRUISES

MAIN HYDROGRAPHIC

CRUISES

MOORING DEPLOYMENTS

XBT ENHANCEMENT

VOS EQUIPMENT WITH IMET STATIONS

GLIDER TESTS OVER JETS AND WBCs

REPEAT GLIDER SURVEYS

REPEAT XBT SURVEYS

ARGO FLOAT DEPLOYMENTS CORAL SEA SEEDING

REGIONAL MODELLING AND ASSIMILATION

IN THE SOLOMON SEA

DEVELOPMENT OF LOCAL MODELING FACILITIES AND EXPERTISE

1ST SW PACIFIC WORKSHOP

AGU SPCZ/SPICE MEETING

SUBMISSION TO CLIVAR SSG

REGIONAL MODEL ASSIMILATION 

IN THE CORAL AND TASMAN SEA

Figure 2: Timetable of major southwest Pacific activities relevant to SPICE objectives.
Section 4. Modeling Strategy 5

4. Modeling Strategy

The SPICE program is stimulated by the need to improve climate prediction at both large scales and regional scales to allow island communities

to benefit from climate research. Model experiments will provide the

necessary linkage between the large-scale questions (e.g., how the subtropical

gyre waters get to the Equator) and the regional issues (e.g., what are the detailed pathways and impacts in the SW Pacific) through downscaling. A variety

of numerical models that include the region (Fig. 3), validated against observations, will help to understand dynamical aspects that cannot be adequately

observed and to identify the observable features, thereby providing guidance

to design the in situ observing program. Model types range from the global,

coupled system to local, high-resolution nested models (Fig. 3, middle). The

latter will be extensively used for this purpose, with downscaling and upscaling

to evaluate mesoscale and island effects. Important operational oceanography

projects concern the Southwest Pacific (e.g., Bluelink, Mercator, and SODA).

BLUElink and Mercator are assimilating systems that offer a nowcast and forecast estimate of the true ocean state that are supported operationally, providing information throughout the experiment. The current operational BLUElink

system provides 0.1◦ × 0.1◦ resolution in the experiment region and 0.9◦ × 0.1◦

resolution in the South Pacific, as shown in Fig. 4, within a single-system downscaling to represent the fine scale bathymetric pathways. This approach can

provide a useful verification to both the proposed regional high-resolution simulation of ocean and climate during the experiment period. In 2010 the operational BLUElink system will be upgraded to have eddy-resolving resolution in

the South Pacific. The assimilating systems can provide realistic boundary conditions to regional models; in return, regional studies contribute to improve the

truthfulness of large-scale models.

SPCZ issue and connection with VOCALS: Although precipitation plays a

key role in tropical climate and its variability, the South Pacific Convergence

Zone is not well simulated in coupled models, which generally fail to reproduce its southeastward bend, instead tending to generate a zonal SPCZ (double ITCZ, Mechoso et al., 1995). This is a major modeling challenge that needs

to be better understood in terms of cause and implications. Biases are apparent in the simulation of both the precipitation climatology and its sensitivity

to anomalous climate forcings. The elimination of this error is a principal goal

of the VOCALS program (Wood et al., 2006). VOCALS focuses on multiple aspects of ocean-atmosphere coupling, including errors in ocean dynamics and

associated effects on surface flux exchange or the parameterization of low-level

marine stratus clouds.
6 Ganachaud et al.—SPICE, Part II. Implementation Plan

Bluelink

Mercator

Forced models

Global 

coupled models

Nesting

Figure 3: The modeling approach will rely on a range of models from coarse climate models to high-resolution,

nested regional models. Upper left: the BLUElink (www.marine.csiro.au/bluelink) operational model grid

and southwest Pacific subdomain. Lower left: the Mercator French operational model (www.mercator-ocean.

fr). Middle: nesting of the Noumea ROMS model from the 2◦ Mercator grid to 1/12◦ grid around New Caledonia (www.ird.nc/UR65/ROMS). Upper right: an IPCC-IR4 global coupled model. Lower right: the OFES highresolution model.

This double ITCZ feature can be compounded by, and even interpreted as,

an eastern extension of the SPCZ “diagonal”: e.g., models may produce an

excessively zonally oriented SPCZ, precipitation that extends too far into the

eastern dry descent region, or precipitation that fills in the region between the

observed SPCZ position and the equator. This interpretation highlights that

severe biases often occur in the eastern SPCZ region, where the southeasterly

trades enter the convection zone. Feedbacks among inflow into a convection

zone, its moisture characteristics, and parameterized convection, are known

from other applications (e.g., Neelin et al., 2003) and may well contribute to

the biases in the SPCZ. Other potential contributions to SPCZ bias may include

eastern Pacific cloud feedbacks or circulation errors, or ocean model biases

(Dai et al., 2003; Takahashi and Battisti, 2007; Kirtman and DeWitt, 1997; Davey

et al., 2002).

Even if models simulate approximately correct precipitation climatologies

relative to the observations, the sensitivity of the models to perturbations in

climate variables such as temperature, moisture, or wind may not be correct.

Such “sensitivity biases” may provide insight into mechanisms of interest, such

as a model’s ability to simulate the interannual variability. At the same time,

they may facilitate the testing of hypotheses about processes controlling the

climatology, offering potential solutions for bias mitigation. As an illustration,
Section 4. Modeling Strategy 7

0°

10°S

20°S

30°S

40°S

50°S

145°E 155°E 165°E 175°E 175°W 165°W

0.4

0.3

0.2

0.1

0

–0.1

–0.2

–0.3

–0.4

Sea level anomaly (m)

0.1° × 0.1° 0.9° × 0.1°

Figure 4: BLUElink ocean prediction system (www.bom.gov.au/bluelink) sea level anomaly with 0.1◦ × 0.1◦

resolution in the SPICE region and 0.9◦ ×0.1◦ in the South Pacific.

consider how the high-frequency variations of the SPCZ could elucidate the significance of inflow to the spatial characteristics of the SPCZ. For anomalously

strong (low-level) trade wind inflow from the eastern Pacific toward the SPCZ,

lower tropospheric moisture along the eastern SPCZ margin will be lowered,

thereby inhibiting convection and precluding the SPCZ from expanding as far

to the east (Lintner and Neelin, 2008). Models with convection schemes lacking appropriate sensitivity to lower tropospheric moisture, or those that produce insufficiently large horizontal gradients in moisture between the eastern

Pacific dry zone and the SPCZ would, under similar trade wind perturbations,

underestimate the changes to the eastern edge of the SPCZ.

Evaluation of such mechanisms in models, such as those in the Coupled

Model Intercomparison Project-3 (CMIP3) archive hosted at Lawrence Livermore National Laboratories, and comparison to existing observations, can inform analysis of observations collected under SPICE, and may aid in the design

of future SPCZ observations.

4.1 Modeling Challenges

Numerical simulations of the oceanic and atmospheric circulation will confront the issues brought up in the scientific background document (Ganachaud

et al., 2007), ordered according to the spatial scales of interest:
8 Ganachaud et al.—SPICE, Part II. Implementation Plan

1. Teleconnections. Some aspects of the connections between the southwest Pacific Ocean and atmosphere and the basin-scale climate system

need to be identified. Teleconnections include the remote atmospheric

forcing, the oceanic pathways to the equator, and its influence on equatorial thermocline waters. On basin scales, those have been debated over

the past 10 years, and a focus on the southwest Pacific role is proposed

here.

2. SPCZ. A survey on how the current coupled atmosphere-ocean models

simulate SPCZ formation, climatology, and variability will be coordinated.

The analysis will be guided by recent developments such as the simple

theory for convective margins (Lintner and Neelin, 2007), which emphasizes the interplay of inflow moisture from the dry region, inflow rate,

convergence/evaporation, and convective threshold. The evolution of

the flow from the stratocumulus-covered region along the coast of South

America, to the transition region of shallow cumuli, and the region of

deep convection in the SPCZ, will be examined in detail.

3. Thermocline water pathways

a. Jets. The Southwest Pacific thermocline circulation in large-scale

models faces important flaws. The formation and dynamics of the

narrow oceanic jets is not very well understood. Large-scale models

produce jets with weak variability because of their limited resolution. A better understanding of the jet dynamics and their formation in the complex topography of New Caledonia and Vanuatu is

important to describe how SEC waters reach the Australian boundary currents.

b. Bifurcation. The SEC bifurcation against Australia occurs over a

large meridional extent, varies in time and depth, and encounters

the Queensland Plateau and the complex Great Barrier Reef system. Its position and variability is crucial to the amount of equatorward water implied by the basin-scale circulation (Qu and Lindstrom, 2002; Kessler and Gourdeau, 2007), with associated current

reversals and possible local impacts on the Great Barrier Reef ecosystem.

Most published simulations find the bifurcation north of its

observed position. Because of the spatial scales involved, an observation system is difficult to establish, and comprehending the bifurcation will heavily rely on accurate modeling.

c. Solomon Sea and route to the equator. The thermocline water flow

within the Solomon Sea is unexplored. High-resolution models

prove highly sensitive to details in their configuration. Because the

thermocline route associated with each strait differs importantly,

their relative contribution needs to be modeled accurately. Climate

simulations use an oceanic resolution that is too coarse to represent

the Solomon Sea and its straits, sometimes forcing the equatorward

flow to circumvent the Solomon Sea so that most thermocline waters reach the EUC via an incorrect route. How such a deviation
Section 4. Modeling Strategy 9

changes the time lag and water mass transformation before SEC waters reach the Equator needs to be understood.

d. EAC. The high variability in the EAC region is associated with complex interaction between boundary currents, eddies, and deep topographic features. The EAC separation, the Tasman Sea variability involving eddy and mean flow interactions, and its reattachment

north of New Zealand are not well understood.

e. Tasman Outflow. The Indian Ocean fate of SEC waters via the Tasman Outflow south of Tasmania determines the partition of intermediate and lower thermocline waters between those two basins.

The Tasman Outflow transport needs to be better comprehended.

It involves interaction between EAC variability, the amount of water

returned to the subtropical gyre via the STCC, and the Tasman Sea.

4. Variability of the ocean-atmosphere system. Both ocean and

atmosphere vary considerably on seasonal, interannual, and decadal

timescales within the equatorial and subtropical region, resulting in fluctuations in the SEC strength, bifurcation latitude, and boundary current

transports. The dynamics of those variations involve thorny interactions

between oceanic waves, islands, and oceanic flow patterns (Maharaj et

al., 2005, 2007; Kessler and Gourdeau, 2007). The challenge is to further explore this variability using intermediate-complexity ocean modeling techniques to better understand the mechanisms and their contributions.

5. Oceanic impacts

a. Pacific Island Countries. Coastal ocean circulation near islands involves large-scale components as well as topographic effects on

both ocean and atmosphere on scales smaller than 10 km. Ocean

temperature results from large-scale currents superimposed with local effects such as upwelling. While sea surface conditions affect

cloudiness, wind strength, cyclone trajectories, and biological dynamics, ocean imprint is essentially unknown in the Southwest Pacific islands.

b. Australia and New Zealand. The substantial warming in Tasmania

associated with an observed shift in the subtropical gyre is expected

to be associated with important changes in rainfall and atmospheric

circulation along the coast. Similarly, changes in oceanic conditions

are expected to influence the Great Barrier Reef and coastal New

Zealand ecosystems.

c. Global climate. The impact of anthropogenic climate change, concomitant with natural variability, will vary substantially with location. To generate climate projections that can be useful to local

communities, global climate projections need to be downscaled, incorporating local ocean influence.
10 Ganachaud et al.—SPICE, Part II. Implementation Plan

4.2 Modeling Objectives

The aforementioned challenges can be addressed through appropriately designed modeling experiments to, specifically,

1. Improve the realism of the southwest Pacific geography/bathymetry in

large-scale models;

2. Understand the Southwest Pacific dynamics and relation with basin-scale

climate;

3. Help optimize observational design strategies;

4. Simulate the small spatial-scale features associated with boundary currents, jets, islands, and straits, and upscale this into climate models;

5. Understand ocean-atmosphere interaction at regional, coastal, and island scales;

6. Adapt, or downscale, global climate projections into results that are useful to island communities;

7. Develop models based on low-cost infrastructure so that participating

countries can create or use their own modeling capacities.

4.3 Modeling Approach

The SPICE modeling activities will draw upon regional expertise and computing facilities hosted in research centers (Melbourne, Wellington, Noumea,

Hawaii, UCLA). We propose to address the SPICE objectives using a variety

of models and interlaced approaches. Six types of model will be used: (1)

basin-scale general circulation model (GCM) with typical resolution ranging

from 20 km–200 km, (2) coupled GCM, data-assimilating (3) reanalyses, (4) operational GCMs, (5) regional (nested) models with typical resolution of 2 km–

20 km, and (6) process, or simplified, models. Objectives 1 and 2 depend upon

4 and possibly 5. Conversely, objectives 4 and 5 rely upon large-scale models, forced or assimilated to provide boundary conditions to regional, highresolution models (“downscaling”). The use of ocean-atmosphere coupled models to address objective 5 entails detailed knowledge of the oceanic conditions

before coupling. Objective 6 is based on IPCC climate projections downscaled

with a regional climate model, e.g., REMO. This approach, along with that of

objective 5, will not only help to test and improve IPCC projection in the Southwest Pacific, but also respond to a high demand of Pacific Island countries who

are the most vulnerable to changes in oceanic and atmospheric conditions.

Overall, regionally improved models are expected to help identify large-scale

model deficiencies and prompt their correction. Such improvement may be

implemented through “upscaling” by embedding a regional model in a largescale model during integration.

4.4 Numerical Models

Basin scale or global scale GCMs, forced: Analysis of existing basin-scale or

global ocean GCMs is useful in identifying the dynamics of the South Pacific
Section 4. Modeling Strategy 11

Ocean. An analysis of the French NEMO model (ORCA05 configuration at 0.5◦

horizontal resolution; 31 levels) pinpointed the main mechanisms driving the

seasonal variability of the southwest Pacific gyre system (Kessler and Gourdeau,

2007). The Japan/U.S. OFES simulation (0.1◦ horizontal resolution, 54 levels)

output is currently available and preliminary studies revealed rich small-scale

structures in the southwest Pacific (Richards et al., 2006). Further analyses on

at least those two models (e.g., McCreary et al., 2007), combined with the limited available observations, will help understanding of the current system and

guide further observations and model improvements such as topography in the

straits, e.g., in the Solomon Sea.

Global scale GCMs, coupled: The oceanic and atmospheric conditions in

the southwest Pacific need to be analyzed in the existing model simulations

(IPCC-AR4/WRCP CMIP3 Multi-Model Data). This will allow validation of the

past and present conditions, and identification of the mechanisms and processes characterizing the role of the southwest Pacific with respect to the basinscale processes. Wind-stress sensitivity experiments using CGCMs will allow

further distinction of the mechanisms involving oceanic and atmospheric (airsea fluxes and SPCZ) dynamics. Analysis of IPCC simulations will also lead to

identification of key indexes and their future projection, such as the potential

for tropical cyclones.

Data-assimilating GCMs: Both reanalysed and operational ocean nowcasts

and forecasts will be available for the SPICE region. Current analysis products include the global SODA (www.atmos.umd.edu/~ocean), ECCO (www.ecco

-group.org), and BRAN (www.cmar.csiro.au/ofam1). Current operational

systems include BLUElink (www.bom.gov.au/oceanography/forecasts and

godae.bom.gov.au) and Mercator (www.mercator.eu.org). Over the timeframe of SPICE several of these systems will undergo system upgrades offering

improved resolution and performance. The objectives of the BLUElink ocean

prediction project are to estimate and predict the ocean state and circulation

in the Australian region which has been implemented as an operational system at the Bureau of Meteorology to service the Australian public. BLUElink

is a global system with enhanced resolution in all of the regional seas around

Australia, including the Coral Sea and Indonesian Throughflow. The timescales

of interest are short- to medium range, providing a 7-day forecast twice per

week. BLUElink resolves mesoscale ocean variability to a resolution of 10 km

at present and extends to 180◦E, therefore including all of the Coral Sea. The

performance of this system is evaluated through a series of ocean reanalyses

(BLUElink ReANalysis, BRAN) 1992–present, making use of historical observations including satellite altimetry, satellite sea surface temperature, and in situ

observations. The BLUElink project is supportive of observational programs

that contribute to the real-time network and can be routinely assimilated by

the operational system. Any delayed-mode observations would also contribute

to posterior validation and ocean reanalyses. The Coral Sea heat content is a

particular target to support (a) coupled atmosphere-ocean modeling for tropical cyclone forecasting, (b) forecasts of coral bleaching within the GBR as a service to GBRMPA and (c) Naval sonar applications. The Coral Sea circulation is

also critical for (a) surface current validation and skill assessment, and (b) spa-
12 Ganachaud et al.—SPICE, Part II. Implementation Plan

tial and temporal variability of the boundary current systems along Australia’s

east coast.

The Mercator global ocean prediction project will provide operational products and reanalyses in the southwest Pacific region for validation and boundary/initial conditions to regional models. Mercator and BLUELink work together under the GODAE framework.

Regional coupled ocean-wave-atmosphere systems and regional ocean data

assimilation schemes are currently being developed within BLUElink and will

be used to investigate short-range prediction and predictability as well as operational coupled tropical cyclone forecasting.

Regional models, forced: Downscaling. Regional models can be nested in

the aforementioned large-scale models to provide higher resolution and topography and parameters that are adapted and tuned to a specific region/experiment. Adaptive mesh refinement tools have demonstrated their efficiency over

the southwest Pacific (e.g., AGRIF, www-lmc.imag.fr/IDOPT/AGRIF used in

conjunction with the oceanic NEMO and ROMS models). This “downscaling”

approach will be used, as well as its atmospheric equivalent (WRF), to address

issues including ocean dynamics, ocean impacts on the ecosystem, local oceanatmosphere interactions, and cyclones. Tools such as AGRIF have a “two-way”

scheme that allows feedback of the fine grid model onto the coarse one, so

that the large-scale model benefits from improved simulation of fine, pointwise structures (e.g., straits or islands) through “upscaling.” High-resolution

models will also be nested in idealized climatological reanalyses and IPCC projections. An improved knowledge of the physical circulation will broaden the

range of applications with, for instance, biogeochemical modeling using the

SEAPODYM model.

Regional models, coupled: Regional ocean-atmosphere coupled models

will permit better understanding of specific ocean-atmosphere interactions (island cloud formation; tropical cyclones) and their evolution with time. ROMS

and WRF are experimentally used in a coupled configuration. The BMRC is

also leading a BLUElink project to develop a regional coupled model for the

tropical regions of Australia, i.e., the North West Shelf and the Coral Sea. This

regional ocean model has been configured to cover the entire region that is influenced by tropical cyclones. The model is based on MOM4 and will nest in

both the ocean reanalysis and the ocean forecast system. The initial target is to

improve the representation of upper ocean heat content for use in coupled regional modeling. Improvements to resolution in the horizontal and vertical will

be assessed relative to cost and stability. This modeling effort may be extended

to focus on higher-resolution modeling of the ocean circulation through improved representation of reef mixing parameterizations for the GBR. The coupled modeling will involve research and development of coupled atmospherewave and coupled atmosphere-ocean models. This improvement would benefit from regional atmospheric-ocean boundary-layer observations.

Process models: Process models are generally used to understand mechanisms of ocean or atmosphere systems. Reduced-gravity (first baroclinic-mode)

ocean shallow-water models have been shown to reproduce important aspects

of the seasonal and interannual variability in the South and southwest Pacific

(e.g., Holbrook and Bindoff, 1999; Bowen et al., 2006; Qiu and Chen, 2006;
Section 4. Modeling Strategy 13

Kessler and Gourdeau, 2007). While much simpler than GCMs, reduced-gravity

models tend to capture the important ocean dynamic processes fundamental

to the Pacific Ocean (e.g., Perkins and Holbrook, 2001; McGregor et al., 2004,

2007). Despite the obvious strengths of first baroclinic-mode models, a more

detailed understanding of the role of bathymetry and the first few baroclinic

modes in the southwest Pacific region as implied by satellite altimeter observations (Maharaj et al., 2005, 2007) would be expected to benefit from process

modeling studies that take better account of the vertical structure. Other linear

models will be used in the same context, such as the “Island Rule” that explains

the boundary current structures on the east coast of islands (Gourdeau et al.,

2007), and analytic planetary models (McCreary et al., 2007).

4.5 Data-Model Intercomparison

The BLUElink team has defined model intercomparison metrics for the Australian and Indian Ocean domain in collaboration with other partners of the

Global Ocean Data Assimilation Experiment (www.godae.org). This region includes the Coral Sea, and the metrics should be re-evaluated within SPICE to

take advantage of the observing system improvements and the dominant characteristics of the circulation, in collaboration with the Mercator group. The GODAE metrics for the South Pacific have been jointly prepared by the BLUElink,

Mercator, and Japanese groups and will serve as a reference for SPICE.

4.6 Sharing Model Output

SPICE will encourage sharing of model simulations within the “CLIVAR data

policy” to foster intercomparison and local, non-commercial applications.

Model simulations can be made available either directly through a local LAS/

opendap server, or through the PRIDE data server.

BLUElink and Mercator ocean nowcast and prediction data will be available for SPICE researchers on an opendap server (godae.bom.gov.au/www.

mercator-ocean.fr) through a user registration. BLUElink reanalyses will also

be provided by a opendap server through the registration as (www.cmar.csiro.

au/ofam1/). See Section “data sharing and policy” below.

4.7 Current and Proposed Regional Modeling

Projects

Table 1 presents a non-exhaustive list of modeling projects that relate to SPICE

objectives.
14 Ganachaud et al.—SPICE, Part II. Implementation Plan

Table 1: A non-exhaustive list of modeling projects that relate with SPICE objectives.

Topic/Project Objectives Institution(s) PI(s) Sponsor Funded

Large Scale

Large-scale air-sea coupling in

connection to ENSO and regional

ocean variability

2 UH/IPRC A. Timmermann

B. Qiu

N. Schneider

NSF TBS

SPCZ formation, climatology, and

variability in CGCMs

1,2 UCLA C.R. Mechoso

D. Neelin

B. Lintner

TBD TBS

Diagnosing and improving

convective processes in large-scale

ocean-atmosphere interaction

1,2 UCLA D. Neelin

B. Lintner

NOAA Yes

BLUElink-Coral Sea 3,4,5 BOM/OMFG G. Brassington Bureau of

Meteorology

Yes

Seasonal and interannual variability

in the NEMO-ORCA 0.5◦ GCM

1,2 IRD/PMEL L. Gourdeau

W. Kessler

IRD

NOAA/PMEL

LEFE

Yes

Role of Coral Sea and remotely

forced Rossby waves on ENSO and

PDV

2,7 Macquarie U.

UTas

BoM

S. McGregor

N. Holbrook

S. Power

Macquarie University Yes

Variability of the circulation in the

SPICE region from high-resolution

ocean models

1,2,4 UH/IPRC/

JAMSTEC

K. Richards

T. Qu

P. Dutrieux

B. Taguchi

H. Saski

NSF/JAMSTEC Yes

Circulation in the Solomon Sea from

high-resolution nested models

1,3,4 IRD/LEGOS/

LEGI

L. Gourdeau IRD/LEGI Yes

Development of a continuously

stratified model to investigate

planetary wave and flow effects in

the southwest Pacific

2,7 UTAS N. Holbrook UTAS TBS

Downscaling of IPCC AR4

projections

1,6 UH/IPRC K. Richards

A. Timmermann

NSF/NOAA TBS

Interior versus western boundary

pathways of South Pacific waters as

identified from ECCO

2 UH/IPRC

CALTECH/JPL

T. Qu

I. Fukumori

NSF/NASA Yes

Climate change detection in the

South Pacific gyre

2,7 UTAS

Macquarie U.

BoM

N. Holbrook

I. Goodwin

S. Power

ARC S

Regional scales and impacts

NZ regional modeling 2,4 NIWA G. Rickard

M. Hadfield

FRST(NZ) Yes

Coastal circulation and upwelling in

New Caledonia

4 IRD P. Marchesiello

J. Lefevre

A. Vega

ZONECO, Noumea

PNEC

Yes

Vulnerability of the South Pacific

Islands to tropical cyclones altered

by ENSO and climate change

6 IRD C. Menkes

P. Marchesiello

M. Lengaigne

ANR

IRD

Yes

Tuna and climate variability in the

Southwest Pacific

6 IRD CPS P. Marchesiello

S. Nichol

ZONECO, Noumea Yes

Infrastructure

Low-cost cluster computer facility

and regional modeling expertise

7 IRD J. Lefevre

P. Marchesiello

IRD Yes

S = submitted

TBS = to be submitted
Section 5. In Situ Observations 15

5. In Situ Observations

Analogous to high-resolution models nested in global circulation models, the

detailed regional SPICE observations will complement large-scale observation

programs, focusing on their unresolved aspects. Satellite ocean observations

are inadequate to observe small scales and/or subsurface flows of interest. The

Argo array provides CTD profiles over the water column; however, the Coral

and Tasman seas are poorly sampled by Argo. As a result, in the Coral Sea most

of our knowledge comes from numerical models and climatologies based on

scanty data. In the Tasman Sea area, the observation database is better supplied, and the high variability calls for targeted process experiments and monitoring. While investigations and further analysis of large-scale climatologies

will be necessary, a major observational effort is needed in the Coral, Tasman,

and Solomon seas. The South Pacific Convergence Zone (SPCZ) was identified

as a major issue that directly relates to the southwest Pacific Ocean and climate.

A major SPCZ-focused field program has been envisaged during the design of

SPICE, and a specific workshop was organized on this issue in December 2007.

Because of the size and remoteness of the SPCZ, a dedicated field experiment

would be costly and would need to involve a large number of scientists and laboratories. Given the present state of knowledge, it was decided to give priority

to numerical model and analytical approaches complemented with analysis of

remote sensing data and reanalysis products, without precluding a future SPCZ

field experiment.

5.1 Observational Challenges

The SPICE field observations are designed to address the following issues raised

in the scientific background document (Ganachaud et al., 2007):

1. Southwest Pacific air-sea fluxes and heat content. Surface heat content

is known to substantially affect weather and climate. On regional scales,

ocean heat content is closely related to seasonal weather extremes in the

Tasman Sea region. In the Coral Sea, it preconditions cyclone trajectories and intensity. On coastal or island scales, surface water properties

can affect weather systems such as the Australian “east coast lows,” and

weather, winds, and cloud formation near islands. Air-sea exchanges are

not accurately known in the southwest Pacific, and both flux products

and upper ocean heat content sampling need to be improved. While recent studies have indicated that ocean advection processes are important

in the Tasman Sea (Roemmich et al., 2005), the relative contributions of
16 Ganachaud et al.—SPICE, Part II. Implementation Plan

advection and heat storage compared to the surface heat flux are poorly

understood, especially on interannual to decadal timescales. The Tasman Sea heat balance requires a specific study with an improved understanding of the heat flux components, particularly their variability, and

how heat is partitioned between the atmospheric fluxes and recirculated

within the gyre.

2. Thermocline pathways

a. SEC inflow and bifurcation. The amount of thermocline water transported by the SEC into the Coral Sea, as well as its redistribution to

the Equator and to the EAC system, has direct climate implications

for the Equator and the Tasman Sea surroundings. It needs to be

observed comprehensively, and to some extent monitored.

b. Jets. The formation process of the jets on the east coasts of Vanuatu

and New Caledonia, and the pathways and delays needed for this

water to cross the Coral Sea determines part of the total time lag

to the Equator or to the Tasman Sea. Those processes, delays, and

transports are not well understood, and the spatial characteristics

of the jets require observational description.

c. Solomon Sea. The transit of thermocline waters in the Solomon Sea

occurs in interleaved currents amid complex reef and island systems. Climatologies suggest that the source of Solomon Sea water merges western boundary flow from the coast of Australia (the

NQC) and SEC waters that arrive directly from the southeast. The

exits to the north redistribute this inflow among the narrow straits

of Vitiaz, St. Georges, and Solomon, each of which implies a different pathway to the Equatorial Undercurrent. The flow structure,

transports, and water mass transformation induces delays and can

modify properties of the EUC waters. The ocean physics of this zone

is almost unexplored.

3. Tasman Sea

a. EAC and partition. Robust estimates of the mean and seasonal cycle of each inflow and outflow component of the circulation in the

Tasman Sea needs to be established, as well as identification of the

source, strength, property variability, and pathways of the major

water masses. From a large-scale perspective, the partition of the

western boundary flow between the Pacific and Indian Ocean gyres

is of major interest. Understanding this partition requires determining the mean and time-varying components of the EAC, the Tasman Front, STCC, and the Tasman Outflow, their variations on interannual to decadal timescales, and the effects of anthropogenic

change.

4. Impacts

a. Coastal circulation. The ocean circulation and biogeochemical properties are poorly known near most Pacific Island nations. How does
Section 5. In Situ Observations 17

the large-scale ocean circulation interact with regional climate and

ocean circulation near the Pacific Islands? How does the ocean circulation and its variations affect ecosystems and populations? These

are questions of major concern to all southwest Pacific nations. Climate change and projected ocean circulation changes will have a

strong, potentially dramatic impact on the southwest Pacific countries, and there is an urgent need to understand current physical

and biochemical ocean conditions, along with atmospheric characteristics and their evolution.

b. Corals. Coral reefs, which constitute the most important natural

resource as well as a natural shield against storm surges in many

islands, are under serious threat from sea surface temperature rise

and increase in ocean acidity through anthropogenic CO2 dissolution. Coral reef health is monitored within specific programs (e.g.,

UNESCO-funded Coral Reef Initiative in the South Pacific program,

www.crisponline.net; Great Barrier Reef management at AIMS,

www.aims.gov.au). Those will benefit from an improved knowledge of temperature and sea level changes associated with changes

in the ocean circulation, from the basin scale to the island scale and

on timescales from months to decades.

5.2 Observational Objectives

The goal of the SPICE field program is to measure and monitor key climaterelevant quantities to help address the aforementioned challenges. The objectives are:

• To complete large-scale surveys of the Coral, Solomon, and Tasman Sea

inflows and outflows with special attention to the WBC and LLWBC;

• To test and apply large-scale in situ and remote monitoring of key climate

quantities, some of which are identified as air-sea fluxes, SEC inflow, Solomon and Tasman Sea inflows and outflows;

• To simultaneously observe/monitor those quantities in different parts of

the basin to accomplish regional mass, heat, and freshwater budgets;

• To carry out regional-scale process surveys on island- and coastal scales

to address local specificities, with possible monitoring.

5.3 Observational Approach

Although many aspects remain to be settled in focused projects, the broad outline of the SPICE field program is clear. It will rely on extensive regional collaboration, on the existing infrastructures and teams, and on regional adaptation

of global observation programs. An important aspect will be the requirement

for quasi-simultaneity of some observations in different parts of the basin. Exploratory surveys will be needed to identify key quantities that require monitoring. Experimental monitoring will precede the design of a long-term monitoring system. SPICE observations have distinct large-scale and regional-scale
18 Ganachaud et al.—SPICE, Part II. Implementation Plan

components, presented in the following two sections. This in situ observation

plan will be completed with remote observations (e.g., SST, SSH, SSS) calibrated

and adapted on the region.

The existing and proposed operations are presented for each aspect and

geographical area in Section 5.3.1–5.3.2; the proposed infrastructure and technology are laid out in Section 5.4.

5.3.1 Large-scale operations

Based on SPICE objectives, existing observation and monitoring programs will

be reinforced in the Coral and Tasman Sea. Those are Argo, the AWS network,

IMOS, the SOOP-IP network, the XBT/HRXBT network, and satellite products

(Fig. 5). A specific field experiment is proposed to complete the large-scale efforts. Figure 6 provides an overview. Oceanographic operations are organized

in three sub-regions: Coral Sea, Tasman Sea, and Solomon Sea.

a. Air-sea fluxes. Improved estimates of exchanges of heat between the

atmosphere and the ocean can be accomplished through in situ and remote

measurements. Direct measurements include hull SST and IMET stations installed on voluntary observing ships (BOM), moored IMET stations, XBT and

HR-XBT lines, and Argo floats with specific equipment. Such in situ measurements are used to calibrate high-resolution satellite SST measurements.

b. Coral Sea. The strategy to measure the SEC inflow to the Coral Sea is

based on regular surveys between the northern tip of New Caledonia and the

southeastern tip of the Solomon Islands. Because the Solomon Islands form a

continuous shallow barrier, such sections (Fig. 4) provide an estimate of the total inflow between 23◦S and the three northern Solomon Sea straits (5◦S). Two

hydrographic cruises have been made to provide an initial description of the

flow, in July 2005 and November 2006. During both cruises, an experimental

glider was deployed which successfully demonstrated the feasibility of those

measurements in this remote region (Gourdeau et al., 2007). The glider data

provided accurate estimates of the transport of narrow near-shore currents.

The SEC inflow monitoring will be continued, with regular seasonal surveys

sampling temperature, salinity, and currents down to at least 2000 m. In addition to hydrographic cruises whose recurrence is necessarily limited, VOS will

be used to deploy deep XBT probes together with Argo floats (see below) between New Caledonia, Vanuatu, and the Solomon Islands. It should be supplemented by surveys south of New Caledonia to estimate the southern branch of

the SEC, the SCJ (Ganachaud et al., 2008).

It is only recently (2006) that Argo floats have begun to infiltrate the Coral

Sea. On the basis of the average currents in the Coral Sea, a deployment every 6

months between New Caledonia and the Solomon Islands would fulfill the 3◦-

spacing Argo requirement. Deploying floats equipped with oxygen sensors will

be of major importance, as this measurement is a key parameter to identify water mass origins and pathways (Sokolov and Rintoul, 2000; Qu and Lindstrom,

2002, 2004; Maes et al., 2007).

c. Tasman Sea. Changes in the heat content in the Tasman Sea are currently monitored using data from the Wellington-Sydney XBT line, Argo floats
Section 5. In Situ Observations 19

10.0 cm/s

cm

90 100 110 120 130 140 150 160 170 180

70

60

50

40

30

20

10

0

Temperature, Salinity,

Chlorophyll, Fluorescence, 

Light absorbtion, Irradiance

Argo deployment 

area. 

Priority Argo 

deployment area. 

Argo: 

50 floats per year total 

X

Ships of Opportunity:

XBT (temperature)

CO2

Plankton

Air Sea Fluxes 

Southern Ocean 

Automated Timeseries:

PULSE Mooring

Tentative IMOS Bluewater Deployment/Observation plan out to June 2008. 

AODAC

AODAC

XL

eMII

Thermosalinographs

High resolution 

satellite

SST and SSH

 2008-2010 

deployments

 Argo floats

live (Jan 2008)

dead

Automated

Weather

Stations

60°N

40°N

20°N

0°

20°S

40°S

60°S

IRD/ECOP

Nouméa

0°E 40°E 80°E 120°E 160°E 160°W 120°W 80°W 40°W 0°W

HR-XBT lines

20°S

25°S

30°S

35°S

40°S

150°E 155°E 160°E 165°E 170°E 175°E 180°

500

450

400

350

300

250

200

150

6°S

10°S

14°S

18°S

22°S

26°S

30°S

140°E 150°E 160°E 170°E 180° 170°W 160°W

25

20

15

10

5

0

–5

–10

–15

–20

–25

Figure 5: Existing large-scale observation and monitoring programs that cover the southwest Pacific. From upper left, and anti-clockwise: Argo in the Coral and Solomon seas and current seeding plans; BOM AWS networks

on land and VOS; IMOS observation program; SST/SSH satellite measurements that require specific local treatments; HR-XBT lines (figure adapted from Roemmich et al., 2005); SOOP-IP VOS thermosalinograph IRD network.

in the Tasman Sea, and, by inference, altimetric sea surface height. To continue to estimate heat storage, the level of Argo deployments in the Tasman

Sea should be maintained or increased and adapted to the shallow topography in the eastern Tasman Sea. The region will also be frequently sampled

by ships hull SST sensors from AWS ships (see section 5.3.1.a above). An inflow/outflow observation system over the Tasman Sea is proposed to improve

the current heat budget monitoring, along with a combination from satellite

altimeter, Argo floats, and other measurements (e.g., Willis et al., 2004). The

system is based on two glider lines and a mooring array (Fig. 6). A first, exper-
20 Ganachaud et al.—SPICE, Part II. Implementation Plan

XBT lines

Argo floats

Surface floats

IMET station

Moorings

Cruise

Glider section

Solomon Strait moorings

Glider/moorings monitoring

Solomon Sea surveys

Coral Sea Argo seeding

SEC surveys (glider/hydro)

SEC monitoring (XCTD/VOS)

EAC surface drifter release

EAC glider monitoring

Norfolk Gap mooring array

Tasman Box HR XBT

TAS outflow mooring array

Figure 6: SPICE field experiment. Simultaneous measurements in different parts of the basin will allow analysis

and monitoring of the mass/heat budget within the area. Exploratory surveys will be followed by experimental

monitoring, with a possible long-term monitoring outcome. All components are planned by participating teams;

some are already funded.

imental glider survey will be tested off Tasmania to monitor the Tasman Outflow. This will be extended to a glider monitoring of the EAC inflow off Brisbane (28◦S), supplemented with Lagrangian measurements through regular release of surface drifters (about 30 drifters/years from the Brisbane-Fiji VOS line

within the East Australia Circulation surface Drifter Program). Additional XBT

probes will be released along a section of the PX30 line similar to that proposed

by the glider to increase the XBT sampling to approximately monthly. These

additional probes (BOM program) will supplement the high-density transects

currently conducted by CSIRO. To the east, a mooring array has been deployed

for 1 year over the Norfolk Gap, where the Tasman Front passes between Norfolk and New Zealand, and extended monitoring is under consideration. And

to the South, plans are underway to deploy a mooring array just south of Tasmania, to monitor the Tasman Outflow.

d. Solomon Sea. Exploratory observations are particularly crucial in the

little-documented Solomon Sea, where the current structure is complicated and

the entire northward SEC outflow occurs through narrow straits. Because the

three Solomon Sea straits (Vitiaz Strait, St. George Channel and Solomon Strait)

are the choke point of the northward-flowing SEC waters, mooring lines should

be deployed there to provide an efficient monitoring of their mass and heat
Section 5. In Situ Observations 21

transport on seasonal to interannual timescales (Fig. 6). The 1985–1986

6-month WEPOCS mooring data suggests two moorings are needed in both Vitiaz and Solomon Straits, as there appears to be significant horizontal shear

in these passages. Single moorings are planned in St. Georges Strait and the

“Indispensable” Channel (10◦S, 161.5◦E). Each mooring will consist of velocity measurements from upward/downward-looking ADCPs to fully resolve the

surface-to-subthermocline flow in each passage. These surface observations

were not resolved by the earlier WEPOCS mooring measurements. Discrete

current meters will measure the deeper currents. Temperature-salinity measurements will also be made at discrete points along the mooring lines, with

higher resolution in the surface to thermocline layers. Nearly all of this instrumentation is already available at CSIRO and SIO.

Hydrographic CTD surveys and preliminary monitoring will be critical in

different parts of the Solomon Sea. The use of gliders will be tested and possibly maintained there, because the region is remote and difficult to access

regularly with an oceanographic ship. A first CTD survey at 11.5◦S was accomplished in August 2007 to estimate the net inflow from the south, corroborated with an experimental glider monitoring of the LLWBC over that same

latitude. Hydrographic and possibly glider surveys inside the Solomon Sea will

be needed to understand how this inflow distributes within the Solomon Sea

and what water mass transformations occur before it exits.

A comprehensive monitoring system will be proposed to survey total mass

and heat transport into the Solomon Sea. The array consists of endpoint moorings measuring geostrophic mass transport, a set of inverted echosounders plus

pressure sensors (PIES) along the section to resolve vertically integrated heat

content and flow across the section, and the aforementioned gliders to deliver

the temperature distribution and flow in the upper 1000 m. It would be complementary to the Strait’s monitoring, assuring that there is no leakage through

smaller passages and that there are no systematic biases in either technique.

Such methodology is being developed and demonstrated in the California Current under the NOAA funded CORC initiative, and would be migrated to the

Solomon Sea after successful operation off California.

e. SEC inflows, outflows, and bifurcation. Monitoring simultaneously the

aforementioned transports will provide an unprecedented description of the

SEC water pathways and associated heat transports. Those include (Fig. 6): the

SEC inflow near 163◦E, the EAC transport at 28◦S, and the Solomon Sea meridional transport at either 10◦S (South Solomon Sea) or 6◦S (Solomon Sea Straits).

These measurements, if concomitant and associated with appropriate modeling experiments, will provide a description of the bifurcation of thermocline

water in the southwest Pacific and its redistribution to the Tasman Sea and to

the Equator. They will also provide an indirect estimate of the NCJ bifurcation processes, as they reach the coast of Australia, which cannot be directly

observed because of its large latitudinal range and the partitioning due to its

encounter with the North Queensland Plateau.

f. Analyses of existing large-scale datasets. While in situ observations in

the southwest Pacific have been scant thus far, efforts have been made to consolidate information from both in situ and remotely sensed data into gridded

datasets (e.g., the Digital Atlas of Southwest Pacific upper Ocean Temperatures
22 Ganachaud et al.—SPICE, Part II. Implementation Plan

(DASPOT, Holbrook and Bindoff, 2000) and the CSIRO Atlas of Regional Seas

(CARS, Dunn and Ridgway, 2002), AVHRR, T/P, Jason1 (Willis et al., 2003)).

These have contributed to our understanding of the seasonal and interannual

variability, water masses, and heat storage variability. Update and analysis of

these datasets will continue as new instruments are deployed to provide new

insights and guidance to the fieldwork planning. A working knowledge of the

historical datasets will also help to provide a more seamless transition from the

XBT to Argo data era.

5.3.2 Regional scale operations

Regional SPICE or SPICE-related operations aim at comprehending (a) local

impacts of oceanic and climate variations on the local environment, and (b)

small-scale processes that relate and possibly influence the large-scale circulation. Regional studies have necessarily diverse objectives, and will integrate,

in most cases, biochemical, fish, or environmental scopes. Because of such diversity, SPICE cannot integrate detailed regional operations. However, the proposed regional collaboration will provide a natural incentive to coordination

with the large-scale operations.

a. Regional process studies. Several aspects of the large-scale thermocline water circulation are interrelated with small scales (e.g., jet formation processes, WBC dynamics against the contorted Australia-PNG coastline, standing

eddies on the EAUC pathway). Because those interactions between strong currents and topographic obstacles impact nutrient availability and biology, specific field studies associating physical and biochemical aspects will be required.

Variations in oceanic conditions’ influence on meteorological processes will,

similarly, entail multidisciplinary experiments. Regional process studies—some

of which are ongoing—will include focused regular CTD-O2-LADCP surveys in

coastal regions with biochemical sampling, mooring lines, and meteorological

parameter measurements.

b. Regional monitoring. Continuous, in situ measurements of the sea surface temperature, the sea surface height, and the sea surface salinity from the

Pacific Islands can be determinant to understanding large-scale ocean circulation as well as local conditions and their impacts (e.g., sea level, coral reefs, cyclone trajectories). Coastal station networks already exist, notably the Tsunami

Warning System in the South Pacific (www.bom.gov.au/pacificsealevel), the

Integrated Marine Observing System (IMOS, www.imos.org.au) on Australian

coasts, and the IRD time series (www.ird.nc/ECOP/siteecopuk/cadres.htm)

on the French Islands. SPICE should support the network of existing time series

extension, perpetuation, and possibly association with other types of measurements (e.g., CO2 monitoring).

5.4 Proposed Observations and Infrastructure

The SPICE field program is based on existing infrastructures, regional and remote. This includes the Hobart CMAR, the Noumea IRD center, Wellington

NIWA, and Scripps Oceanographic Institution.
Section 5. In Situ Observations 23

a. Hydrography. Standard hydrographic surveys consist of observations of

temperature, salinity, and velocities over the water columns—or at least 2000 m.

SPICE-proposed hydrographic sections are high resolution and integrate oxygen measurements to identify water mass origins. Temperature and salinity allow calculation of the velocity relative to a given depth, which, combined with

ADCP and/or drifter measurements, provide a detailed description of the velocity field. Hydrographic vessels that can be made available to SPICE projects

include the 66 m RV Southern Surveyor (CSIRO-Hobart), the 28-m RV ALIS (IRDNouméa), large ships from the French national fleet (www.ifremer.fr/flotte/

navires), the 70-m RV Tangaroa, and 28-m RV Kaharoa (NIWA-Wellington),

and associated hydrographic instruments and engineers from the respective institutes.

b. Gliders. Gliders are autonomous underwater platforms that are moved

over the water column by modifying their buoyancy and “glide” using wings

that confer a horizontal velocity associated with their vertical displacements.

Gliders orient themselves to accomplish the equivalent of a slow hydrographic

section associated with a variety of measurements including temperature and

salinity, over the upper water column. The present technology has been tested

in the Coral Sea (Gourdeau et al., 2007), then in the Solomon Sea (Kessler et al.,

2008), providing successful, repeated measurements of the transports across

a 900 km distance and across strong currents. Gliders are expected to be an

important contribution to monitor boundary current, especially in regions of

difficult accessibility. Gliders are currently operated in collaboration between

Scripps Oceanographic Institution, NOAA, and IRD. The CSIRO (CMAR-Hobart)

was funded to purchase gliders and develop an operational facility.

c. XBT from VOS. Expendable Bathythermograph (XBT) probes deployed

from commercial vessels on their routes have been able to provide repeated

measurements of the upper 400 m water column in different parts of the world

and over the past 35 years (www.jcommops.org/soopip). XBT data are the

main source of knowledge of oceanic variability, especially in the southwest

Pacific Ocean where little other data exist. Over 10 years of XBT measurements

are now available along each transect of the “Tasman box” (Fig. 6) between Australia (28◦S), Fiji (18◦S, 178◦E), and New Zealand, with sampling typically occurring approximately four times each year (Roemmich et al., 2005). These highdensity transects are fundamental to the proposed observation network. Funding is secured to maintain them in the next 5 years, and to upgrade (deeper

probes; higher frequency is considered within the SPICE context). XBT lines

between Fiji and Honolulu and Noumea and Japan are currently maintained

(Fig. 6). A new line between Noumea and Guadalcanal is being started to monitor the SEC inflow using a combination of Argo float releases and XBT probes.

d. Drifters. Floats from the Argo program (www.argo.ucsd.edu) will be

deployed during SPICE. The present Argo coverage is very low in the Coral and

Tasman seas because of the topographic configuration: floats get entrained in

boundary currents close to the coast and are pushed toward the shore by the

prevailing winds during their surface phase, and eventually beach. The long

ARGOS surface transmission times may be a major cause of this drift. But, to

our knowledge, about half the floats that crossed the Coral Sea have so far “survived” the WBC transit, and while this area would be opportune for float de-
24 Ganachaud et al.—SPICE, Part II. Implementation Plan

ployments with fast Iridium® transmitters (thereby reducing the surface drift),

it appears reasonable to continue deploying standard floats. Floats equipped

with an oxygen sensor will be especially relevant as strong oxygen gradients

permit efficient identification of water origins.

Satellite-tracked surface drifting buoys provide a convenient platform to

measure surface velocities and temperature or more properties in some cases

(Lumpkin and Pazos, 2006). Regular deployment is planned during all seafaring cruises. Through a collaboration of the Bureau of Meteorology, NOAA,

and the University of Melbourne, floats will be deployed to monitor specifically the Lagrangian properties and transport of the East Australia Current (“the

East Australia circulation surface drifter program”). Preliminary deployments

have started; the target is to deploy 30 drifters/year for 5 years off the coast of

Queensland using volunteer ships.

e. Moored instruments. Moored subsurface current meters, including

upward-looking ADCPs, are capable of providing the needed time series of the

currents and transports in the Solomon Straits, and have proven relevant in

the Indonesian Straits during the recent International Nusantara STratification

ANd Transport program (INSTANT) project (www.ldeo.columbia.edu/res/

div/ocp/projects/instant.shtml). Nearly all of this instrumentation and

expertise is already available at CSIRO and SIO; deployment and maintenance

will be carried out during hydrographic surveys in collaboration with IRD.

There are presently no moored surface stations in the Tasman-Coral Sea.

Surface meteorological moorings are essential to obtaining high-quality meteorological observations of wind, air, and sea temperature, humidity, pressure, radiation, precipitation, and salinity which can be used to infer air-sea

fluxes. Such instrumentation will be deployed in the Southern Ocean within

the Integrated Marine Observing Network (IMOS), an Australian, governmentfunded 4.5-year program to provide infrastructure to observe the coastal and

open ocean around Australia. While similar instrumentation in the SPICE region would be of high value to the determination of air-sea fluxes, its deployment and maintenance costs are very high, and no funding source has been

identified at this point. A Deep Ocean Assessment and Reporting of Tsunamis

(DART) buoy will be installed, and a cost-effective solution to equip this buoy

with meteorological sensors is under consideration.

The moorings, inverted echosounders/pressure sensors (PIES), and gliders

necessary to the South Solomon Sea integral transport measurement system

would be provided by SIO, with funding from the NOAA CORC project. Two

moorings are required at the end points of the section carrying enough microcat T/S sensors to calculate dynamic height differences along the section. The

PIES instruments will be located on the seafloor and measure bottom pressure

with extreme precision, as well as acoustic travel time to the sea surface as a

proxy for heat content/dynamic height. Their (and the mooring) data will be

interrogated and telemetered to shore by the gliders. Several gliders would operate along the section simultaneously to provide sufficient temporal resolution

for the transport changes to be captured.

f. Surface measurements from VOS. VOS equipped with real-time transmitting automatic weather stations (AWS) provide repeated data that are highly

valuable to air-sea flux estimation. There are currently eight vessels that par-
Section 5. In Situ Observations 25

ticipate in the Australian Volunteer Observing Fleet (AVOF) program, the New

Zealand RV Tangaroa and the Noumea-based RV ALIS. Their routes include

coastal Australia (Queensland to South Australia), Bass Strait, and the Tasman

Sea (Fig. 5). The network is being extended, and several of these ships will be

fitted with ship hull SST sensors through the IMOS program (previous section).

There is some capacity to take advantage of these ships for additional observations, such as surface drifter or XBT deployments.

Sea surface salinity (SSS) measurements have proven useful to understand

important aspects of climate variations in the South Pacific as those reflect

the precipitations—notably the SPCZ and the ocean circulation. A network

of manual and automated sea surface temperature and salinity measurement

systems mounted on commercial ships using a water intake has been covering the southwest Pacific Ocean since 1956. This network now transmits its

data in real time (www.jcommops.org/soopip/ and www.legos.obs-mip.fr/

observations/sss/). The importance of SSS in the climate system has motivated the development by European and USA/Argentina space agencies of dedicated satellite missions (SMOS and Aquarius) to enhance global observations,

and the in situ network is expected to establish a ground basis for calibration.

5.5 SPICE-Related Observational Projects

Table 2 provides a non-exhaustive list of the observational projects that respond to the aforementioned SPICE objectives and challenges.
26 Ganachaud et al.—SPICE, Part II. Implementation Plan

Table 2: A non-exhaustive list of the observational projects that respond to the aforementioned SPICE objectives and challenges.

Topic/Project Obs. Component Institution(s) PI(s) Sponsor Funded

SEC Inflow

South Equatorial Current and

jets from modeling and

observations

5.3.1.b IRD

PMEL

Scripps

L. Gourdeau

W. Kessler

R. Davis

IRD-LEFE

NOAA

CORC

Yes

Solomon Sea

Solomon Sea inflow from the

South

5.3.1.d IRD

PMEL

Scripps

C. Maes/L.

Gourdeau

W. Kessler

R. Davis

IRD

NOAA

CORC

Yes

Circulation in the Solomon Sea

from models and observations

5.3.1.d IRD

PMEL

S. Cravatte

A. Ganachaud

G. Eldin

LEFE/IDAO

ANR

OPBC

Yes

S

Yes

Transports through the

Solomon Straits

5.3.1.d CSIRO

Scripps

IRD

J. Sprintall

S. Wijffels

A. Ganachaud

NSF

Australia

ANR

S

S

S

Integral mass/heat transport

entering the Solomon Sea

5.3.1.d Scripps U. Send

R.Davis

D. Rudnick

NOAA, 5-year

program

approved

Annual

renewals

pending

Tasman Sea

EAC glider monitoring from

Hobart and Brisbane

5.3.1.c CSIRO S. Wijffels CSIRO

IMOS

Yes

Tasman Front at Norfolk Ridge 5.3.1.c NIWA P. Sutton

M. Bowen

FRST Field

completed

HRXBT Brisbane-Fiji and

Sydney-Wellington

5.3.1.c CSIRO K. Ridgway CSIRO Yes

East Australia Circulation

Surface Drifter Program

5.3.1.c BOM/NOAAU

Melbourne

G. Brassington BOM/NOAA Yes

Tasman Outflow Mooring array 5.3.1.c CSIRO K. Ridgway IMOS TBS

Population connectivity in two

oceans: a multispecies

comparative study

5.3.1.c Macquarie U.

UTAS

CSIRO

L. Beheregaray

N. Holbrook

P. England

R. Babcock

ARC S

Climatological Data

Historical rainfall maps and

South Pacific Convergence Zone

(SPCZ) reconstruction for

1951–2007

5.3.1.a NIWA

NOAA/NCDC

U. Melbourne,

IBIMET-CNR

A. Lorrey NOAA Yes

Relative importance of

bathymetry, mean flow, and

wind stress in altimetric

signatures of Rossby waves

5.3.1.f Macquarie U.

NOCS

UTas

A. Maharaj

P. Cipollini

N. Holbrook

Macquarie U.

ARC

TBS

Operational Programs

AWS and SST on VOS 5.3.1.a BOM Yes

High-resolution SST analysis

over the Australian domain

5.3.1.a BOM/AIMS BOM Yes

Regional Applications

Coastal circulation and

upwelling in New Caledonia

5.3.2.a IRD P. Marchesiello

A. Ganachaud

ZONECO Yes
Section 7. Applications and Training 27

6. Data Management and

Availability

The availability of SPICE data should follow the CLIVAR policy (www.clivar.

org/data/data_policy.php), which includes quality controls and free, unrestricted access. SPICE involves different types of data, each of which is in most

cases associated with existing servers or programs (e.g., Argo floats, operational

oceanography projects). A central web page will inform about planned experiments and redirect toward appropriate data servers.

An important issue will be to make Southwest Pacific data available for research, training, and applications (e.g., availability under useful formats). The

Pacific Region Integrated Data Enterprise (PRIDE, apdrc.soest.hawaii.edu/

PRIDE/) is a NOAA-sponsored program to create integrated data products to

address issues related to vulnerability of coastal and island communities to climate, marine ecosystems, and climate-related risk management. In line with

that, the U.S. Global Climate Observing System (GCOS) Program manages

NOAA’s activities at the Asia-Pacific Data Research Center (APDRC, apdrc.

soest.hawaii.edu/). The APDRC has in turn developed the infrastructure

necessary to make data resources readily accessible and usable to researchers

and general users. The APDRC, via the U.S. GCOS Program, will be able to integrate servers for new model simulations and data types related to SPICE.

7. Applications and Training

The bridge between the large-scale ocean and atmosphere circulation and their

local impacts on environment and eventually sustainability will be established

in collaboration with regional agencies and universities. On basin and global

scales, the ultimate purpose of SPICE and follow-ups is to improve climate prediction. Such improvement will be of direct benefit to Pacific Island Countries

(PICs) whose climate is strongly influenced by ENSO. But a major SPICE objective is to improve knowledge and prediction of the ocean conditions in the

southwest Pacific, pertaining to a wide range of temporal and spatial scales,

from basin scales to island effect scales. During SPICE, tools will be developed
28 Ganachaud et al.—SPICE, Part II. Implementation Plan

(e.g., database access, model simulation diagnostics), as well as independent

projects that are specific to a location or process. This development must include appropriate training to serve local interests and respond to the demand

from Pacific Island country governments to improve their appreciation of vulnerability to changes in the oceanic and climate environment and their capacity to respond to such changes.

SPICE, in collaboration with the Pacific Islands Global Ocean Observing

System (PI-GOOS, hosted by SOPAC, the Pacific Islands Applied Geoscience

Commission, based in Suva, Fiji), will endorse and encourage training initiatives. Training can cover a wide range of topics, some of which were already

mentioned in this document (e.g., sea level rise, oceanic conditions and coral

health, tropical cyclones) with specific research or application projects, classes

on database usage and developing capacity building in operational oceanography.

8. SPICE Legacy

SPICE is a process study to identify southwest Pacific features that are relevant

to climate. The efficacy and reliability of the proposed measurements on climate prediction will be assessed through the modeling efforts. This will pinpoint the key quantities that may lead to the development of a long-term South

Pacific monitoring system to deliver data for initialization and calibration of climate forecasts. Regionally, SPICE will lead to improved ocean condition knowledge and forecasts, with direct applications to Pacific Island countries.

Through the CLIVAR data policy, measurements and model outputs will be

made publicly available through appropriate data servers (see Section 6). Relevant training will help build the capacity in local communities to use southwest

Pacific data and forecasts for pertinent response to societal demand.
Section 9. References 29

9. References

Bowen, M.M., P.J.H. Sutton, and D. Roemmich (2006): Wind-driven and steric

fluctuations of sea surface height in the southwest Pacific. Geophys. Res.

Lett., 33, L14617, doi:10.1029/2006GL026160.

Dai, Y., R. Yu, X. Zhang, Y. Yu, and J. Li (2003): The impact of low-level cloud

over the eastern subtropical Pacific on the “double ITCZ” in LASG FGCM-0.

Adv. Atmos. Sci., 20, 461–474.

Davey, M., M.M. Huddleston, K.R. Sperber, P. Braconnot, F. Bryan, D. Chen, R.

Colman, C. Cooper, U. Cubasch, P. Delecluse, D. DeWitt, L. Fairhead, G.

Flato, C. Gordon, T. Hogan, M. Ji, M. Kimoto, A. Kitoh, T. Knutson, M. Latif,

H. Le Treut, T. Li, S. Manabe, C. Mechoso, G. Meehl, S. Power, E. Roeckner,

L. Terray, A. Vintzileos, R. Voss, B. Wang, W. Washington, I. Yoshikawa, J. Yu,

S. Yukimoto, and S. Zebiak (2002): STOIC: A study of coupled model climatology and variability in tropical ocean regions. Climate Dyn., 18, 403–420.

Dunn, J.R., and K.R. Ridgway (2002): Mapping ocean properties in regions of

complex topography. Deep-Sea Res., 49, 591–604.

Ganachaud, A., W. Kessler, S. Wijffels, K. Ridgway, W. Cai, N. Holbrook, M.

Bowen, P. Sutton, B. Qiu, A. Timmermann, D. Roemmich, J. Sprintall, S.

Cravatte, L. Gourdeau, and T. Aung (2007): Southwest Pacific Ocean Circulation and Climate Experiment. Part I. Scientific Background. NOAA

OAR Special Report/International CLIVAR Project Office, CLIVAR Publication Series No. 111. (www.ird.nc/UR65/SPICE).

Ganachaud, A., L. Gourdeau, and W. Kessler (2008): Bifurcation of the subtropical south equatorial current against New Caledonia in December 2004 from

a hydrographic inverse box model. J. Phys. Oceanogr., 38, 2072–2084.

Gourdeau, L., W.S. Kessler, R.E. Davis, J. Sherman, C. Maes and E. Kestenare

(2007): Zonal jets entering the Coral Sea. J. Phys. Oceanogr., in press.

Holbrook, N.J., and N.L. Bindoff (1999): Seasonal temperature variability in the

upper southwest Pacific Ocean. J. Phys. Oceanogr., 29, 366–381.

Holbrook, N.J., and N.L. Bindoff (2000): A digital upper ocean temperature atlas

for the southwest Pacific: 1955–1988. Aust. Meteorol. Mag., 49, 37–49.

Kessler, W.S. (2008): Gliders in the Solomon Sea. Presentation at Western Pacific

Geophysics Meeting, Cairns, Australia, 31 July 2008.

Kessler, W.S., and L. Gourdeau (2007): The annual cycle of circulation of the

southwest subtropical Pacific, analysed in an ocean GCM. J. Phys. Oceanogr.,

37, 1610–1627.

Kirtman, B.P., and D.G. DeWitt (1997): Comparison of atmospheric model wind

stress with three different convective parameterizations: Sensitivity of tropical Pacific Ocean simulations. Mon. Wea. Rev., 125, 1231–1250.
30 Ganachaud et al.—SPICE, Part II. Implementation Plan

Lintner, B.R., and J.D. Neelin (2007): A prototype for convective margin shifts.

Geophys. Res. Lett., 34, L05812, doi:10.1029/2006GL027305.

Lintner, B. R. and J. D. Neelin (2008): Eastern margin variability of the South

Pacific Convergence Zone. Geophys. Res. Lett., 35, L16701, doi:10.1029/

2008GL034298.

Lumpkin, R., and M. Pazos (2006): Measuring surface currents with Surface Velocity Program drifters: the instrument, its data, and some recent results.

Chapter 2 in Lagrangian Analysis and Prediction of Coastal and Ocean Dynamics (LAPCOD), A. Griffa, A.D. Kirwan, A.J. Mariano, T. Ozgokmen, and

T. Rossby (eds.), Cambridge Univ. Press, Cambridge, UK, 39–67.

Maes, C., L. Gourdeau, X. Couvelard, and A. Ganachaud (2008): What are the

origins of the Antarctic Intermediate Waters transported by the North Caledonian Jet? Geophys. Res. Lett., in press.

Maharaj, A.M., P. Cipollini, and N.J. Holbrook (2005): Observed variability of the

South Pacific westward sea level anomaly signal in the presence of bottom

topography. Geophys. Res. Lett., 32, L04611, doi:10.1029/2004GL020966.

Maharaj, A.M., P. Cipollini, N.J. Holbrook, P.D. Killworth, and J.R. Blundell

(2007): An evaluation of the classical and extended Rossby wave theories in

explaining spectral estimates of the first few baroclinic modes in the South

Pacific Ocean. Ocean Dyn., 57(3), 173–187, doi:10.1007/s10236-006-0099-5.

McCreary, J.P., R. Furue, T. Jensen, H.-W. Kang, B. Bang, T. Qu, and T. Miyama:

Interactions between the Indonesian Throughflow and circulations in the

Indian and Pacific Oceans. Prog. Oceanogr., in press.

McGregor, S., N.J. Holbrook, and S.B. Power (2004): On the dynamics of interdecadal thermocline depth and sea surface temperature variability in the

low to mid-latitude Pacific Ocean. Geophys. Res. Lett., 31, L24201,

doi:10.1029/2004GL021241.

McGregor, S., N.J. Holbrook, and S.B. Power (2007): Interdecadal sea surface

temperature variability in the equatorial Pacific Ocean. Part I: The role

of off-equatorial wind stresses and oceanic Rossby waves. J. Climate, 20,

2643–2658.

Mechoso, C.R., A.W. Robertson, N. Barth, M.K. Davey, P. Delecluse, P.R. Gent, S.

Ineson, B. Kirtman, M. Latif, H. Le Treut, T. Nagai, J.D. Neelin, S.G.H. Philander, J. Polcher, P.S. Schopf, T. Stockdale, M.J. Suarez, L. Terray, O. Thual,

and J.J. Tribbia (1995): The seasonal cycle over the Tropical Pacific in General Circulation Models. Mon. Wea. Rev., 123, 2825–2838.

Neelin, J.D., C. Chou, and H. Su (2003): Tropical drought regions in global

warming and El Niño teleconnections. Geophys. Res. Lett., 30(24), 2275,

doi:10.1029/2003GL018625.

Perkins, M.L., and N.J. Holbrook (2001): Can Pacific Ocean thermocline depth

anomalies be simulated by a simple linear vorticity model? J. Phys.

Oceanogr., 31, 1786–1806.

Qiu, B., and S. Chen (2006): Decadal variability in the large-scale sea surface

height field of the South Pacific Ocean: Observations and causes. J. Phys.

Oceanogr., 36, 1751–1762.

Qu, T., and E. Lindstrom (2002): A climatological interpretation of the circulation in the western south Pacific. J. Phys. Oceanogr., 32, 2492–2508.
Section 9. References 31

Qu, T., and E. Lindstrom (2004): Northward Intrusion of Antarctic Intermediate

Water in the Western Pacific. J. Phys. Oceanogr., 34, 2104–2118.

Richards, K., N. Maximenko, F. Bryan, and H. Sasaki (2006): Zonal jets in the

Pacific Ocean. Geophys. Res. Lett., 33, L03605, doi:10.1029/2005GL024645.

Roemmich, D., J. Gilson, J. Willis, P. Sutton, and K. Ridgway (2005): Closing

the time-varying mass and heat budgets for large ocean areas: The Tasman

Box. J. Climate, 18, 2330–2343.

Sokolov, S., and S. Rintoul (2000): Circulation and water masses of the southwest Pacific: WOCE section P11, Papua New Guinea to Tasmania. J. Mar.

Res., 58, 223–268.

Takahashi, K., and D.S. Battisti (2007): Processes controlling the mean tropical

Pacific precipitation pattern. Part II: The SPCZ and the southeast Pacific

dry zone. J. Climate, 20, 5696–5706.

Willis, J.K., D. Roemmich, and B. Cornuelle (2003): Combining altimetric height

with broadscale profile data to estimate steric height, heat storage, subsurface temperature, and sea-surface temperature variability. J. Geophys. Res.,

108(C9), 3292, doi:10.1029/2002JC001755.

Wood, R., and the VOCALS Scientific Working Group (2006): VOCALS-Regional

Experiment: Scientific Programme overview, www.eol.ucar.edu/

projects/vocals.

Section 10. Glossary of Acronyms (for Parts I and II) 33

10. Glossary of Acronyms (for Parts I and II)

AAIW Antarctic Intermediate Water

ACC Antarctic Circumpolar Current

ADCP Acoustic Doppler Current Profiler

AGRIF Adaptive Grid Refinement In Fortran

AGU American Geophysical Union

AIMS Australian Institute of Marine Science

ANR Agence Nationale de la Recherche (Funding agency, France)

APDRC Asia-Pacific Data Research Center

ARC Australian Research Council

AVHRR Advanced Very High-Resolution Radiometer

AVOF Australian Volunteer Observing Fleet

AWS automatic weather stations

BMRC Bureau of Meteorology Research Centre

BODAS BLUElink Ocean Data Assimilation System

BOM Bureau of Meteorology (Australia)

BRAN BLUElink ReANalysis

CARS CSIRO Atlas of Regional Seas

CGCM coupled general circulation model

CALTECH California Institute of Technology

CLIVAR Climate Variability and Predictability

CMAR CSIRO Marine and Atmospheric Research

CMIP3 Coupled Model Intercomparison Project-3

COADS Comprehensive Ocean-Atmosphere Data Set

CORC Consortium on the Ocean’s Role in Climate

CSIRO Commonwealth Scientific and Industrial Research

Organization

CTD Conductivity-Temperature-Depth

DART Deep-ocean Assessment and Reporting of Tsunamis

DASPOT Digital Atlas of Southwest Pacific upper Ocean Temperatures

EAC East Australia Current

EAUC East Auckland Current

ECC East Cape Current

ECCO Estimating the Circulation and Climate of the Ocean

ENSO El Niño-Southern Oscillation
34 Ganachaud et al.—SPICE, Part II. Implementation Plan

ERS1/2 European Remote-Sensing Satellites1/2

ERSST Extended Reconstructed Sea Surface Temperature

EUC Equatorial Undercurrent

FRST Foundation for Research, Science and Technology

GBR Great Barrier Reef (Australia)

GBRUC Great Barrier Reef Undercurrent

GCM general circulation model

GCOS Global Climate Observing System

GODAE Global Ocean Data Assimilation Experiment

HRXBT High-Resolution Expendable Bathythermograph

IMET Improved Meteorology system for marine meteorological

observations

IMOS Integrated Marine Observing System

INSTANT International Nusantara Stratification and Transport

IPCC Intergovernmental Panel on Climate Change

IPCC-AR4 Intergovernmental Panel on Climate Change Fourth

Assessment Report

IPRC International Pacific Research Center

IRD Institut de Recherche pour le Développement

ITCZ Intertropical Convergence Zone

JAMSTEC Japan Marine Science and Technology Center

JPL Jet Propulsion Laboratory

LADCP lowered acoustic Doppler current profiler

LAS Live Access Server

LEFE Les Enveloppes Fluides de l’Environement (Funding agency,

France)

LEGI Laboratoire des Ecoulements Géophysiques et Industriels

LEGOS Laboratoire d’Etudes en Géophysique et Océanographie

Spatiales

LLWBC low-latitude western boundary current

MOM4 Modular Ocean Model 4

MOMA Modular Ocean Model—Array processor version

NCDC National Climatic Data Center

NCJ North Caledonian Jet

NEMO Nucleus for European Modeling of the Ocean (NEMO)

NGCC New Guinea Coastal Current

NGCUC New Guinea Coastal Under Current

NIWA National Institute of Water and Atmospheric Research

NOCS National Oceanography Centre, Southampton

NQC North Queensland Current

NOAA National Oceanic and Atmospheric Administration

NTIS National Technical Information Service

NVJ North Vanuatu Jet

NSF National Science Foundation
Section 10. Glossary of Acronyms (for Parts I and II) 35

OAR Oceanic and Atmospheric Research [NOAA]

OFES Ocean General Circulation Model For the Earth Simulator

OMFG Ocean and Marine Forecasting Group

ORCA A Global Ocean configuration of OPA (Ocean Parallélisé)

PACSWIN PACific Source Water Investigation

PBECS Pacific Basin Extended Climate Study

PDV Pacific Decadal Variability

PIES Pressure Gauge Equipped Inverted Echo Sounder

PI-GOOS Pacific Islands Global Ocean Observing System

PINs Pacific Island Nations

PMEL Pacific Marine Environmental Laboratory [NOAA]

PNEC Programme National d’Etudes Cotières

PNG Papua New Guinea

PRIDE Pacific Region Integrated Data Enterprise

PSU practical salinity units

REMO Max-Planck Institut für Meteorologie Regional climate Model

RiCom River, Coast and ocean model

ROMS Regional Ocean Modeling System

RV Research Vessel

SAM South Annular Mode

SAMW SubAntarctic Mode Water

SCJ South Caledonian Jet

SEAPODYM Spatial Ecosystem And Population Dynamics Model

SEC South Equatorial Current

SECC South Equatorial Countercurrent

SIO Scripps Institution of Oceanography

SLW Subtropical Lower Water

SMOS Soil Moisture and Ocean Salinity

SODA Simple Ocean Data Assimilation

SOEST School of Ocean and Earth Science and Technology

SOOP-IP Ship Of Opportunity Programme Implementation Panel

SOPAC South Pacific Applied Geoscience Commission

SPCZ South Pacific Convergence Zone

SPESMW South Pacific Eastern Subtropical Mode Water

SPICE Southwest Pacific Ocean Circulation and Climate Experiment

SPMW South Pacific Mode Water

SPREP Pacific Regional Environment Programme

SSG Scientific Steering Group

SSH Sea Surface Height

SSS Sea Surface Salinity

SST Sea Surface Temperature

START Global Change System for Analysis, Research, and Training

STCC Subtropical Countercurrent
36 Ganachaud et al.—SPICE, Part II. Implementation Plan

STF Subtropical Front

STMW Subtropical Mode Water

SVJ South Vanuatu Jet

T/P TOPEX/Poseidon

TAO Tropical Atmosphere Ocean

TF Tasman Front

TO Tasman Outflow

UCLA/AOS University of California Los Angeles/Department of

Atmospheric and Oceanic Sciences

UH University of Hawaii

UNESCO United Nations Educational, Scientific and Cultural

Organization

USP University of South Pacific

UTas University of Tasmania

VAMOS Variability of the American Monsoon Systems (CLIVAR/WCRP)

VOCALS VAMOS Ocean-Cloud-Atmosphere-Land Study

VOS Voluntary Observing Ship

WBC Western Boundary Current

WE Wairarapa Eddy

WEPOCS Western Equatorial Pacific Ocean Circulation Study

WOCE World Ocean Circulation Experiment

WRCP World Climate Research Programme

WRF Weather Research and Forecasting

XBT eXpandable Bathy Thermograph

XCTD expendable conductivity-temperature-depth

ZONECO Zone Economique Exclusive de Nouvelle Calédonie (Applied

oceanic and shore research, New Caledonia)