Jumbo Content

ROSES Proposals

Radiative Products for the PACE Era

PI: Emmanuel Boss - University of Maine
Co-PI: Robert Frouin (Scripps Institution of Oceanography, University of California San Diego)
Hyperspectral radiative measurements spanning from UV to NIR such as will be available with PACE's OCI will improve our ability to estimate radiative products compared to the current ones by constraining atmospheric transmission at many more wavelengths, narrower bands and into a wider range of wavelengths than current satellites. Together with PACE's expanded suite of biogeochemical products, such as absorption by phytoplankton and dissolved organic materials, the improved radiative products will allow for improved constraints of aquatic biogeochemical rate process, for example, near-surface primary production and photo-oxidation.

It has recently become apparent that current radiative products are not optimal for users. In particular, to compute rates of photochemical and photobiological processes the necessary input is the sub-surface scalar irradiance and its attenuation with depth spanning from UV and across the visible. However, current ocean color radiative products are currently limited to above surface downwelling spectral irradiance and PAR.

Here we propose to expand the radiative products suite distributed by NASA's Ocean Biology and biogeochemistry Processing Group (OBPG) to include both daily and instantaneous (at the time of satellite passage) spectral downwelling and scalar irradiance below the surface, ocean albedo and the appropriate attenuation function to propagate them to different depths. We will provide OBPG the algorithms for these novel products and work closely with them on their implementation. In addition, we will generate software tools (subroutines) for users interested in obtaining band integrated PAR and UVA radiative values at a given depth or integrated over a depth range (e.g., mixed- layer). Prior to PACE, we will create and test demonstration algorithms using data from HICO (spectral and PAR) and MOBY (UVA) and validated using radiometry data available on SeaBASS, PANGAEA, profiling floats and from different mooring sites.

We will reach out to the relevant communities (e.g., ecosystem and biogeochemical modelers) early in this project to insure that the algorithms we produce are fit-for-purpose and that these communities are ready to ingest the relevant products as soon as they become available online.