Diffuse UV Reflectance of the Global Ocean from DSCOVR EPIC
Abstract
Earth Polychromatic Imaging Camera (EPIC) of the Deep Space Climate Observatory (DSCOVR) collects images of the full illuminated disk of Earth from the L1 vantage point between the Earth and the Sun. High cadence of EPIC observations, which produces up to 8-12 images of the same area from dawn to dusk, is a unique feature of EPIC dataset providing a dense time series. We have adapted the Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm for the EPIC processing, including cloud detection, aerosol retrieval, and atmospheric correction over global land and water.
This presentation will focus on the water leaving reflectance (rw) in the EPIC UV bands 340 and 388nm. The UV reflectance is a strong indicator of abundance of phytoplankton and dissolved organic matter that strongly absorb in the UV. EPIC data show a maximal reflectance rw 0.08-0.09 at 388nm for oligotrophic (nutrient poor) waters, in agreement with in-situ measurements and theoretical modeling. It also clearly shows the nutrient-rich eutrophic and major upwelling regions where UV reflectance rapidly drops. Moreover, despite rather coarse spatial resolution ( 10km), high cadence allows EPIC to capture spatio-temporal dynamics of phytoplankton blooms in the global ocean, resulting in strong inverse correlation of the EPIC's rw in the UV with the MODIS ocean color product. The monthly climatology of the EPIC's rw in the UV is a significant improvement over one obtained from OMI.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.A43B..07L
- Keywords:
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- 0321 Cloud/radiation interaction;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 0370 Volcanic effects;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSESDE: 3322 Land/atmosphere interactions;
- ATMOSPHERIC PROCESSES