Satellite-measured phytoplankton phenology in the California Current

OBJECTIVES:

The purpose of this project is to use satellite-measured ocean color time series to quantify changes in phytoplankton phenology over the California Current region. The timing of specific events in biological seasonal cycles has direct implications for the success and structure of other trophic levels and is a sensitive indicator of climate change. Strong spatial heterogeneity in biological seasonal cycles over the study region requires that multiple metrics of phenology be developed and tested to determine which are appropriate locally and which might be applicable across the entire region. These will be used to develop maps of spatial geography in phytoplankton phenology and quantify anomalies and any trends in the phenology metrics. Phenology changes will then be compared to local and basin-scale physical variability characterized by sea-surface temperature, wind and climate-related indices such as the El Nino-Southern Oscillation, the Pacific Decadal Oscillation, and the North Pacific Gyre Oscillation to provide insight into regionally dependent linkages to forcing mechanisms. Development, testing and initial focus will be on Sea-viewing Wide Field-of-view Sensor data and its 13-year mission time-window (Sept. 1997-Dec. 2010). In the final phases of the study, phenology metrics will be applied to Coastal Zone Color Scanner (1979-1986) and Moderate Resolution Imaging Spectroradiometer Aqua (2002-present) data to extend the analysis to over three decades. This proposal addresses the second NASA Strategic Goal: to "expand scientific understanding of the Earth and universe in which we live" and specifically contributes to three Earth system sciences Objectives (2.1.3, 2.1.5, 2.1.7) articulated in the 2011 NASA Strategic Plan.