## Abbreviations  
The following abbreviations are used in this manuscript: \begin{tabular}{l l} ABS & Arctic and Boreal Shrublands \\ AG & Arctic Grasslands \\ AVHRR & Advanced Very High Resolution Radiometer \\ BRDF & Bidirectional Reflectance Distribution Function \\ CRO & Croplands \\ DBF & Deciduous Broadleaf Forests \\ DNF & Deciduous Needleleaf Forests \\ EBF & Evergreen Broadleaf Forests \\ EC & Eddy Co-variance \\ ECMWF & European Centre for Medium-Range Weather Forecasts \\ ENF & Evergreen Needleleaf Forests \\ EVI & Enhanced Vegetation Index \\ FluxSat & Fluxnet Data Fused with Satellite Images \\ GOME & Global Ozone Monitoring Experiment \\ GOSIF & the Global, OCO-2-based SIF Product \\ GPP & Gross Primary Productivity \\ IGBP & International Geosphere-Biosphere Programme \\ LTDR & Land Long-Term Data Record \\ MF & Mixed Forests \\ MODIS & Moderate Resolution Imaging Spectrometer \\ NDVI & Normalized Difference Vegetation Index \\ NIRv & Near-infrared Reflectance of Vegetation \\ OCO-2 & Orbiting Carbon Observatory-2 \\ PAR & Photosynthetic Active Radiation \\ PW & Permanent Wetlands \\ SIF & Solar Induced Fluorescence \\ SM & Soil Moisture \\ SV & Savannas \\ T & Temperature \\ TG & Temperate Grasslands \\ TS & Temperate Shrublands \\ VPD & Vapor Pressure Deficit \\ \end{tabular}   
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