Besides empirical algorithm with the Blue-Green Ratio

fluorescence remote sensing of Chlorophylls is also an important and valid method for retrieving chlorophyll-a concentration in the ocean

especially for Case Ⅱ waters and the sea with algal blooming.This study reviews the history of initial cognitions

investigations and detailed approaches towards chlorophyll fluorescence

introduces the biological mechanism of fluorescence remote sensing and main spectral characteristics such as the positive correlation between fluorescence and chlorophyll concentration

the Red-Shift phenomena.In addition

there are many influential factors which increase the complexity of fluorescence remote sensing

such as fluorescence quantum yield

physiological status of various algae

substance with related optical property in the ocean

atmospheric absorption etc.Based on these cognitions

scientists have found two ways to calculate the amount of fluorescence detected by ocean color sensors: fluorescence line height and normalized fluorescence height.These two ways are currently the foundation to retrieve chlorophyll-a concentration in the ocean.As the in-situ measurements and synchronous satellite data are accumulated

the fluorescence remote sensing of chlorophyll-a concentration in Case Ⅱ waters should be understood more deeply and new algorithm could be expected.