Objective:

To understand the influence of environmental variability on fluctuations in marine populations, we must describe the environment's primary spatial and temporal patterns, and the mechanisms responsible for climate change. Our U.S. GLOBEC project focuses on decadal ocean variability in the North Pacific using retrospective analyses of atmospheric and oceanic observations. We expect to identify key environmental indicators that provide direct dynamical, rather than simply correlative, links between decadal changes in the physical environment and fluctuations in marine populations.

The initial focus was on preparing the data bases for use in the project. The project currently focuses on the analysis of the historical oceanic and atmospheric data sets we developed or customized. The analysis concentrates on describing the primary patterns of and mechanisms for seasonal, interannual, and decadal variability in:

• Wind stress, wind stress curl, and turbulent mixing
• Large scale ocean-atmosphere interactions
• Sea surface and subsurface temperatures
• Ocean stratification and mixed layer depth
• Open ocean and coastal surface Ekman processes
• Transports of mass, momentum, and energy
• Oceanic and atmospheric teleconnections.

Questions:

Our research is designed to address five main questions:

1. What are the major patterns of decadal change in ocean fields and processes in the NEP?
2. What are the mechanisms leading to decadal oceanic change, and wherein is the source of this change?
3. How do basin-scale and local processes interact in the major regions of the NEP to produce the oceanic responses observed in these regions?
4. How do the seasonal cycles in the different regions of the NEP vary on decadal scales?
5. How are the patterns, processes, and mechanisms of decadal change in the NEP similar to and different from those operating on seasonal to interannual scales?