The Index for Coastal Eutrophication Potential (ICEP) is an indicator for the potential of riverine nutrient export to sustain new production of non-diatoms phytoplankton biomass; it is calculated by comparing the N, P and Si loading to the Redfield ratios expressing the requirements of marine diatoms growth. A negative value of the ICEP indicates that Si is present in excess over the other nutrients and would thus indicate a low likelihood of HAB development. Positive values of ICEP indicate an excess of N or P over Si, which may lead to blooms of non-diatom, possibly harmful algae species. The ICEP represents the potential impact of the riverine delivery to the coastal zone. Here the ICEP value is presented with the MODIS satellite derived chlorophyll-a measurements. Areas with high chlorophyll-a measurements often correspond to high ICEP values, including the Bay of Bengal, parts of south-east Asia and the Baltic Sea. postal