Remote Sensing Of Solar Induced Chlorophyll Fluorescence From Satellites, Airplanes And Ground-Based Stations

With the advent of existing high resolution spectrometers in space (GOSAT, GOME-2, OCO-2), global observations of solar induced chlorophyll fluorescence (SIF) became feasible for the first time. The potential of SIF is to provide an independent and more direct proxy for photosynthetic activity and, depending on retrieval methodology, be less susceptible to atmospheric scattering. Empirically, strong linear correlations between SIF and gross primary production (GPP) have been shown in several studies, albeit with somewhat different slopes per biome type. Here, we show the first full year of data acquired by the Orbiting Carbon Observatory-2, which provides unprecendendet spatial resolution (1.3.2.3 km), data volume (more than 1 million measurements per day) and signal-to-noise ratios (>500). In addition, we show the first direct validation of space-based OCO-2 SIF measurements using the newly built Chlorophyll Fluorescence Imaging Spectrometer (CFIS), an imaging spectrometer optimized for SIF retrievals and OCO-2 validation. To conclude, we will present a new ground-based measurement system developed by UCLA for long term observations of SIF at ground-based stations.