A 13-Year Time Series of Surface PAR over the World Oceans from SeaWiFS and MODIS Data

Robert Frouin, Scripps Institution of Oceanography, UCSD, rfrouin@ucsd.edu (Presenter)
Bryan Franz, NASA Goddard Space Flight Center, bryan.a.franz@nasa.gov

A global, 13-year record of photo-synthetically available radiation (PAR) at the ocean surface (9-km resolution) has been generated from SeaWiFS, MODIS-Aqua, and MODIS-Terra data. The PAR values are essentially obtained by subtracting from the solar irradiance at the top of the atmosphere (known) the solar energy reflected by the ocean-atmosphere system (satellite-derived) and absorbed by the atmosphere (modeled). Observations by individual instruments, combinations of two instruments, and three instruments are considered in the calculations. Spatial and temporal biases between estimates from one, two, or three instruments are determined and corrected, resulting in a consistent time series for variability studies. Uncertainties are quantified on daily, weekly, and monthly time scales for the various instrument combinations from comparisons with in situ measurements. Modes of seasonal and non-seasonal variability are investigated, and the correlative behavior of PAR and chlorophyll concentration is examined. PAR monitoring will continue with current and future satellite ocean-color sensors, and the methodology will be extended to generating UV-A and UV-B irradiance.

Presentation Type:  Poster

Session:  Other   (Wed 10:00 AM)

Associated Project(s): 

• Related Activity

Poster Location ID: 160