Qualitative Estimation of Sun-Induced Chlorophyll Fluorescence (SIF) Using Sentinel-3 OLCI Sensor Data

This paper evaluates the ability of Sentinel-3 satellite data to qualitatively estimate chlorophyll fluorescence, a direct indicator of the physiological state of vegetation. Estimates are compared in absorption zones, O2-B and O2-A, using data collected in three different ecosystems. The proposed method calculates the simple ratio of radiance outside and inside the oxygen absorption bands. Results show that the method, using the O2-A absorption band, can effectively predict field-derived chlorophyll fluorescence measurements. The observed differences between the variants are discussed and the importance of considering errors and biases in the measurements is pointed out. This qualitative approach based on satellite data offers potential for improving spatial and temporal resolution in monitoring chlorophyll fluorescence at global or regional scales.