workshop with the goal of exploring current major challenges in sea ice prediction and identifying new methods, observations, and technologies that might advance seasonal to decadal sea ice predictive capabilities through improved understanding of the Arctic system. The content of this report is largely informed by the discussions held during the workshop and is augmented by the committee’s deliberations.

A key theme resonating throughout the report is the importance of a coordinated and integrative approach to advance sea ice prediction. In fact, fundamental to the success of the workshop was a purposeful approach taken to foster a dialogue between polar researchers, agency representatives, and end users. The committee concludes that there is a need for this dialogue to be sustained well beyond the confines of the workshop format. A committed and deliberately integrative approach, founded on a sustained and coordinated conversation among the user, modeling, and observation communities, is necessary to:

• Identify and address key gaps in our fundamental understanding of the Arctic environment and its connection to the global climate system;

• Balance high-priority stakeholder needs against realistic predictive capabilities;

• Foster coordinated support of this work within the private and public sectors;

• Provide guidance in allocation of resources to support the most promising avenues in addressing the most pressing needs.

This deliberately integrative approach would not only help address the challenges identified in Chapter 2, but is also necessary to effectively implement many of the strategies laid out in Chapter 3.

In this spirit, there are several key overarching challenges, not unique to the topic of sea ice prediction, that hinder advancements in our predictive capabilities:

• Treating the Arctic sea ice cover not in isolation, but as an integral part of the complex Arctic system which, in turn, is an integral element of the global system;

• Understanding how the recent regime shift in the Arctic sea ice cover from predominantly multiyear to first-year ice affects the processes governing the atmosphere-sea ice-ocean system, the power of statistical prediction methods, the validity of current numerical models and their parameterizations, and observational requirements, including instrument design; and

• Clearly defining the needs of the growing number of stakeholders, many with additional and more sophisticated requirements, and balancing these needs against realistic predictive capabilities.

The detailed needs of the diverse stakeholder community are reflected in an equally diverse set of temporal and spatial