(A) Project Goal
- [ POBE-Project-Summary.pdf ]
Using US and international observational datasets combined with physical and biological models, this project investigates the mechanisms of climate-related variability in three Pacific boundary ecosystems: Gulf of Alaska (GOA) and California Current System (CCS) referred to as the Northeast Pacific (NEP), the Humboldt or Peru-Chile Current System (PCCS), and the Kuroshio-Oyashio Extension (KOE) region. (The figure below shows the regional domains)
(B) Research Activities -
(1) Assess to what extent, and by what mechanisms, large-scale climate modes (e.g. PDO, NPGO, ENSO, and potentially others) drove coherent changes across Pacific boundary ecosystems over the period 1960-2007.
(2) Quantify and explain how changes in regional ocean processes (e.g. upwelling, transport dynamics, mixing and mesoscale structure) at each boundary control phytoplankton and zooplankton dynamics. Then, use those results to test the degree to which changes in each study region reflect bottom-up control of their respective ecosystems.
(3) Quantify the extent to which changes in the statistics of shorter-period events (e.g. intraseasonal oscillation, timing of spring transitions) during different phases of the longer-period climate modes (e.g. PDO, NPGO and others) determine the climate state of boundary-current ecosystems.
(4) Explore the range of uncertainties in the response of regional ocean dynamics and their ecosystems to climate change using forcing scenarios from selected climate model integrations that are part of the IPCC 2007 report. This last objective begins an assessment of the potential impacts of climate change on regional ocean ecosystems, a topic poorly addressed in the latest IPCC report, but the chief instrument for most fisheries and coastal management.
(C) Main Hypothesis -
This diagram below shows the main path of the hypothesis of the proposal. The hypothesis can be grouped in three principal sets. (H1) Linking large-scale physical variability to regional scales through comparison with available observations of the physical state of the regional oceans along the Pacific Boundaries. (H2) Understand the relative importance of regionally dependent forcing vs. large-scale. How much of the variability along the boundary is coherent and linked to modes of climate variability of the Pacific Ocean. (H3) Link changes in the physical state at the regional scale with changes in transport dynamics and nutrient flux. Our main hypotheses is that ecosystem variability in the Pacific boundaries is driven by changes in nutrient flux. Hence we seek for direct links between changes in horizontal and vertical transport to observed measures of ecosystem state.
(D) Research Tasks organization -
The research tasks are grouped in 5 topic areas that cover the following geographical locations (color coded): Pacific Basin, Northeast Pacific (NEP), Peru-Chile Current System (PCCS), the Kuroshio Region (KOE) and Cross-Bundary Synthesis Activities.
A detailed description of these research activities for each group is available on the [ Research Activities ] page.