Operational Nowcasting of Algal Blooms in the Baltic Sea Using MERIS and MODIS
Abstract
The Swedish Meteorological and Hydrological Institute are operating a daily satellite based monitoring service of cyanobacterial blooms in the Baltic Sea during the summer period. The main data source has been the AVHRR (NOAA) sensor, which are reliable but have low spatial and radiometric resolution. To improve the service, data from MERIS (ENVISAT) and MODIS (AQUA EOS), which has higher spatial and radiometric resolution, has been included. The disadvantage using MERIS or MODIS separately is the longer revisit intervals and smaller swath width compared to AVHRR, which makes it difficult to get daily coverage. By combining MODIS and MERIS this problem can be minimized. A method to detect cyanobacterial blooms in MODIS data using normalized water leaving radiance in the 551 and 670 nm bands, has been made operational and adapted to similar MERIS bands (555 and 665 nm). Differences between MERIS and MODIS data are generally small and dissimilarities are often due to discrepancy in flag definitions. Future work will focus on data availability since both sensors are operating beyond their technical lifetime.
- Publication:
-
ESA Living Planet Symposium
- Pub Date:
- December 2010
- Bibcode:
- 2010ESASP.686E.337H