Two bloom products were developed for the Oregon coast based on the observed change between running 8-day composite chlorophyll-a (CHL) and fluorescence line-height (FLH) products obtained by the MODerate Resolution Imaging Spectraradiometer aboard Aqua (MODIS-Aqua). These products were optimized to detect bloom onset via satellite in Oregon s coastal waters, a region typified by high frequency biological variance yet pervasive cloud cover (see McKibben et al. 2012, JGR-Oceans). The products are based on running relative differences between successive 8-day products: a current composite (an average of the previous 8 days) and a reference composite (an average of the 8-day period immediately preceding the current composite). The reference is differenced from the current, then the result is normalized to the reference. Resulting daily imagery highlights the geographic locations of greatest relative change observed between weekly average CHL or FLH over time, providing a way to track onset and advection of active blooms over time. Note the product is optimized to work best in Oregon s coastal waters, although it is operational further offshore and to the north or south as satellite coverage permits (coverage is increasingly better to the south and worst further offshore and to the north of Oregon). The bloom product accessible from this page is based on MODIS-Aqua FLH and shows the percent relative change in FLH over time. THIS IS AN EXPERIMENTAL PRODUCT: intended strictly for scientific evaluation by professional marine scientists.