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The meeting broke into two different groups to deal with the Comparative Analysis and Climate Change documents. (Coverage will be heavier with the Comparative Analysis working group.) The groups were attempting to have drafts suitable for review prepared by the end of 2001. Review will be by members of the SSC not involved in writing the document.

Nate Mantua provided the Climate Change Working Group Summary. The focus of this group is on how to use models to bridge scales between climate change and population dynamics in the study regions. Nate's group will base their paper on schematic diagrams of conceptual models of the study areas and will compare these conceptual models to the approaches used in each regional study. Time-space diagrams will be used with important factors highlighted. The working group plans to identify the scales contributing to variability. Understanding the scales at which variability can be introduced sheds light on system predicability. If mesoscale turbulence is the driving force in variability, the system will not be terribly predictable. If its PDO, the system may be much more predictable. The working group also intends to provide advice on how move from GLOBECs regional studies to climate scale issues. An organizing theme of this report will be the role and relative importance of large scale forcings (PDO, NAO, ENSO) and teleconnections to the the dynamics of th various regions studied in U.S. GLOBEC.

The following is a summary of the discussions that took place in the Comparative Analysis Working Group.

#### The structure of the Comparative Analysis document will be:

- Introduction
- Overview of the program
- Key issues in synthesis
- Key issues in comparative analysis
- Key Hypotheses
- Syntheses
- Conceptual and numerical models
- Physical models
- Biological models
- Coupled Bio-Physical models

Questions of diversity are difficult to address within GLOBEC due to its focus on target species. However, given the biological collections made during GLOBEC, the question may be handled to some extent. Even if diversity cannot be adequately addressed, questions of species richness can be useful as can discussions of 'physical or other diversity.'

Regime shifts should roll into this but may be more suitable in the climate change report. The time-space scales of various processes are important to the project as a whole. The climate change report will cover this in some detail.

Are there common/unique process occuring in the various regions?

#### A list of possible processes might be:

- Buoyancy driven flow (CGOA)
- Downwelling
- Cross-shelf transport
- Stratification (GB)
- Retention/loss
- Cross-shelf transport
- Along-shelf transport
- Sea/Ice dynamics (SO)
- Topographic control (Which mechanisms?)
- Behaviors involved (Implications for the organisms?)
- Top down versus bottom up control

Stratification is important in each system and retention also plays a large role. Retention and dispersal could be used as an organising theme, perhaps in terms of defining retentive areas in each region. Retention/dispersal may be due to topographic control and we'd need to describe the mechanisms behind this. Organism behavior also effects retention and loss. Does the interaction of life history strategy and retention/loss dynamics increase or decrease population level variability? Loss from bank systems may actually increase variability so it may be helpful to compare bank to shelf ecosystems.

The group could focus on retention/loss as the organising theme but perhaps could couch the question in terms of organism life history strategy. This would allow the group to weave in questions of top down/bottom up controls and trophic cascade versus physical forcing. An example of this might be Aluetian Low changing mixed layer depth and impacting phytoplankton production.

Life histories of target organisms might be excellent fodder for comparison because one could compare Calanus on the east coast and Neocalanus on the west. One could discuss the similarities and important differences between these organisms. For instance, Calanus finmarchicus is a broadcast spawner and can tune production to short term conditions, while Pseudocalanus is a brood spawner and is unable to begin a second clutch until the existing clutch has been spawned and so is better tuned to a steady state. Likewise Euphasia superba eggs are found at depths of about 1000 m. At such depth stable conditions exist and there are no changes in the antarctic circumpolar current. Euphasia pacifica's eggs are at the surface and experience variable conditions. The contrast between these two species and their environments would be an interesting study.

We know that the time scales of physical processes are important to life history features (which probably occur on time scales on the order of months). Processes such as stratification have linkages to climate level processes. We could bring in top down versus bottom up control and highlight the physical processes which might lead to one or the other in each system.

Statistical analyses may provide an important part of what we need to know. Solow et al.'s zooplankton work was based on PCA but uses 1st order autocorrelation.

Bob Beardsley suggested looking at wind stress and heat flux. Timing is important in setting up stratification on the Southern Flank of Georges Bank and may have very important implications for the success of cod/haddock (match-mismatch). Approximately 30 years of wind data are available for the Southern Flank and additional information is available in the ICES Backward Facing Workshop Reports.

Basin scale processes should be brought into the discussion in some way. Climate models are capable of showing NAO shifts and may allow for some degree of predictability. And it is becoming clear that some large scale process is effecting Calanus populations on either side of the Atlantic. Perhaps a way to start would be to overlay the various GLOBEC regional study areas on a map of global pressure anomalies

#### The list of topics includes:

- Address the limitations of the GLOBEC approach. We should discuss the areas GLOBEC cannot address and identify those things we simply cannot handle at the current time.
- Identify the next phases for research. What will the successor to GLOBEC style programs look like? On which areas should it focus?
- Examine the scale transfer question. How do we move from small scale processes to regional and larger scales?
- Discuss important basin scale processes.
- Address a number of base level bio-physical or ecological processes which are important such as:
  - Cross-shelf transport
  - Top down/bottom up
  - Life history strategy
  - Retention/Dispersal
- Identify how information produced by GLOBEC could be used in developing better management strategies and/or techniques.

Zack Powell noted that a focus on fisheries management alone was an unnecessary limitation of the potential usefullness of the Program. There are many areas in which GLOBEC technology can be employed, such as: transportation (shipping cost reduction), dumping, mining, MPAs, tourism, search/rescue. We have tools which can be applied in any number of arenas.

Mark Ohman asked about paleo-oceanographic work being conducted recently as some of it is very informative. The Program may want to investigate this area to look for evidence of coherent fluctuations in different systems. The could lead to and understanding of the variance structure/spectrum in any particular system. Mark pointed to sardine/anchovy and Alaska midden records as examples.

Modeling Section - US GLOBEC has not yet attempted to utilize climate models such as the NCAR model. Some of these models operate at a very large scale. The IPCC has archived climate change scenarios. Previously these archives contained only temperature fields. Recently, however, wind fields are also saved. One hundred year scenarios also exist for NAO and PDO. The Canadian Climate Center has archived model runs as well. The various climate models seem fairly consistent in terms of temperature, but differences exist for precipitation, etc. Can/should this information be integrated into US GLOBEC activities? This may be better addressed in the Climate Change Paper, but Zack and Cisco can add section to the comparative analysis paper dealing with climate change model.

The biological modeling section should examine energy flow and ecosystem structure to get an idea of how the system works. A section dealing with network analysis of the sort that Platt, Vesina, Steele et al. have constructed should be added. Modeling frameworks such as Ecopath and Ecosim should also be mentioned.

#### Areas outstanding are:

- Modeling Approaches (Dale)
- Climate Modeling Connection (Zack/Dale/Cisco)
- Network Modeling
- Haddock/cod on Browns, Western, Georges, Rockall banks (Crowder/Parrish)
- Topographic effects/control on circulation, stratification and buoyancy driven
- Understanding life history in terms of physics

This document should serve as a blueprint or implementation plan for synthesis.

Mike Fogarty provided Working Group Outline to the SSC.