The western and eastern boundary regions of the tropical Pacific Ocean are the primary conduits of tropical-subtropical interaction. These regions thus play crucial roles in ocean dynamics and climate variability on both regional and global scales. To examine this critical region, the Eastern Pacific Task Team was formed.
Amongst other charges in its terms of reference, the priorities of the Eastern Pacific Task Team include:
- Engaging regional experts and institutions within the eastern Tropical Pacific boundary region
- Defining observational requirements, including time and space scales that should be resolved
- Building capacity for improved sustained observing capability
- Facilitate the development of a regional research project, which may contribute guidance for a sustained observing system
Task Team to focus on the eastern Tropical Pacific boundary region; giving priority to engaging regional experts and institutions. In addition to defining needed observations, goals of the TT could include: (a) Capacity building for improved sustained observing capability; and (b) Facilitation of the development of a regional research project, which may contribute guidance toward a sustained observing system.
Task Team Publications
- Jul. 2015: Terms of Reference (see below)
Task Team Details
Task Team Members and Affiliations:
- Yolande Serra, University of Washington, USA*
- Ken Takahasi, Instituto Geofiscio del Peru, Peru*
- Eric Alfaro, Universidad de Costa Rica, Costa Rica
- Simon De Szoeke, Oregon State University, USA
- Boris Dewitte, Laboratoire d’Etudes en Géophysique et Océanographie Spatiale, France
- Dimitri Gutierrez, Intituo del Mar del Peru (IMARPE), Peru
- Rodney Martinez, Centro Internacional para la Investigación del Fenómeno de El Niño, Ecuador
- Willington Renteria, Instituto Oceanográfico de la Armada Oceanografía, Ecuador
- Efrain Rodriguez-Rubio, Independent, Colombia
- Wolfgang Schneider, Universidad de Concepcion, Chile
- Yan Xue, NOAA Climate Prediction Center, USA
Terms of Reference
For the eastern Pacific boundary region:
- Determine the observational requirements, including time and space scales that should be resolved, either through Backbone contributions or through specialised/pilot contributions to TPOS.
- Develop observational strategies and design plans for the region, taking into account, as appropriate, the readiness of technology and feasibility of measurements, the evolving Backbone Observing System, and guidance being developed by other TPOS 2020 Task Teams.
- Provide guidance as required to the Backbone Observing System Task Team and, as required, other Task Teams on strategies and plans for the region.
- Foster interaction and collaboration between the TPOS and other international programs that have an observational focus in the tropical eastern Pacific boundary region.
- Provide guidance on implementation and explore potential opportunities to collaborate with regional institutions for the implementation and maintenance of TPOS and its national components, and to evolve process-oriented boundary measurements towards a sustained system.
By Feb. 1, 2015 develop TORs for a Task Team to focus on the eastern Tropical Pacific boundary region, giving priority to engaging regional experts and institutions In addition to defining needed observational, goals of the TT could include: (a) Capacity build for improved sustained observing capability; and (b) Facilitate the development of a regional research project, which may contribute guidance for a sustained observing system.
The western and eastern boundary regions of the tropical Pacific Ocean are the primary conduits of tropical-subtropical interaction. These regions thus play crucial roles in ocean dynamics and climate variability on both regional and global scales, and need to be adequately covered by the TPOS.
January 2014 Workshop White Paper 8a (Takahashi et al) discussed a number of scientific drivers for interest in the Eastern Pacific boundary region:
- Seasonal and sub-seasonal climate prediction, including for the coastal region
- Role of the eastern Pacific in ENSO diversity;
- Thermocline feedback processes in the eastern Pacific;
- Coastal dynamical and biogeochemical processes;
- Convective processes in the eastern Pacific and the connections to ENSO;
- Decadal variability and climate change; and
- Regional impacts and applications.
The paper provided a number of TPOS-related recommendations including:
- Develop strategies for the TAO array, in particular along the equatorial waveguide (to 95°W) and examine the potential for high-density Argo monitoring farther to the east;
- Promote and support a network of sustained coastal surface (sea level, SST, and wind) and subsurface measurements, including suitable biogeochemical variables;
- Organize an international meeting in the SE Pacific region, including resource holders; and
- Explore bilateral or regional cooperation mechanisms for ship deployment.
Guidance from the 1st TPOS 2020 Steering Committee meeting
The SC concluded the activities for the western and eastern boundary regions needed to be considered separately (cf the conclusions of the La Jolla Workshop).
The discussion revisited the scientific questions and issues discussed in La Jolla, as summarised above. From a scientific perspective, two areas were highlighted:
- The need to improve understanding of upper ocean and coupled processes in the equatorial eastern Pacific, such as warming from regional northerly wind anomalies, and upper ocean feedbacks for equatorial Kelvin Waves impinging on the western Pacific coastal region. There are a number of long-standing errors in climate models in the eastern Pacific which contribute to systematic errors in seasonal and sub-seasonal forecasts and longer-term climate simulations.
- The need to observe and monitor CO2, pH, chlorophyll and oxygen, and associated oceanic transports and air- sea fluxes, in the near-equatorial and coastal zone. This represents a significant knowledge gap.
In terms of benefit and societal impact, the reasons for making the eastern part of TPOS a focus are numerous and include:
- Near real-time monitoring of equatorial/coastal Kelvin wave and coastal and eastern Pacific winds which have a number of ecosystem and regional climate impacts;
- Monitoring of intraseasonal atmospheric equatorially propagating disturbances (e.g. MJO or convective Kelvin) for mid-range forecasting;
- Initialization and validation of seasonal forecast models, including coupled modes;
- Monitoring of upper ocean water mass formation and circulation; and
- Monitoring of ocean biogeochemistry for management of marine ecosystems and associated fisheries.
There is strong potential to strengthen regional collaboration by bringing together a core group of researchers across regional agencies. Persistent serious errors in representing the thermocline in models may make the eastern Pacific a good focus for a systematic errors workshop (see also the Modelling and Data Assimilation Task Team).
The importance of re-implementing the 95°W line of TAO was discussed at length, noting that in the past, high levels of vandalism made sustaining these moorings extremely difficult; new technologies may reduce the risks and make fixed-point observing feasible. As with other regional activities, any focused regional work around the far eastern Pacific boundary will inform requirements and options for the Backbone.
The need to improve data sharing in near real time was also noted. TPOS 2020 has no mechanism to facilitate discussions on data sharing, but it could be part of a change project in concert with others. The Permanent Commission for the South Pacific (CPPS) should also be engaged. The potential for a coastal air-sea interaction process study was also discussed.
In making a decision to form a Task Team, the Steering Committee noted that all of the other Task Teams (Backbone, Planetary Boundary Layer, Biogeochemistry and Modelling and DA) will be undertaking work relevant to the eastern Pacific and thus there is a requirement for strong coordination.
In developing TORs for a Task Team to focus on the eastern Tropical Pacific boundary region, the Steering Committee suggested giving priority to engaging regional experts and institutions. In addition to defining needed observations, goals of the TT could include: (a) Capacity building for improved sustained observing capability; and (b) facilitation of the development of a regional research project, which may contribute guidance for the sustained observing system.
The Task Team should report to the Steering Committee at its annual meetings and otherwise as required. The TT will mainly work by correspondence and web meetings.