● The photosynthetic pathway (C3, C4) impacts the relationship between CO2 uptake and SIF, which helps to interpret satellite signals.

● TROPOMI SIF agrees well with the seasonality of crop gross primary production (GPP) when accounting for C3/C4 fractionation.

● TROPOMI SIF is highly correlated with USDA reported crop productivity at the county scale.

He, L.,  Magney, T.,  Dutta, D.,  Yin, Y.,  Köhler, P.,  Grossmann, K., et al. ( 2020).  From the ground to space: Using solar‐induced chlorophyll fluorescence (SIF) to estimate crop productivity. Geophysical Research Letters,  47, e2020GL087474. https://doi.org/10.1029/2020GL087474