A global 0.05° dataset for gross primary production of sunlit and shaded vegetation canopies (1992–2020)

Distinguishing gross primary production of sunlit and shaded leaves (GPPsun and GPPshade) is crucial for improving our understanding of the underlying mechanisms regulating long-term GPP variations. Here we produce a global 0.05°, 8-day dataset for GPP, GPPshade and GPPsun over 1992-2020 using an updated two-leaf light use efficiency model (TL-LUE), which is driven by the GLOBMAP leaf area index, CRUJRA meteorology, and ESA-CCI land cover. Our products estimate the mean annual totals of global GPP, GPPsun, and GPPshade over 1992-2020 at 125.0±3.8 (mean ± std) Pg C a-1, 50.5±1.2 Pg C a-1, and 74.5±2.6 Pg C a-1, respectively, in which EBF (evergreen broadleaf forest) and CRO (crops) contribute more than half of the totals. They show clear increasing trends over time, in which the trend of GPP (also GPPsun and GPPshade) for CRO is distinctively greatest, and that for DBF (deciduous broadleaf forest) is relatively large and GPPshade overwhelmingly outweighs GPPsun. This new dataset advances our in-depth understanding of large-scale carbon cycle processes and dynamics.

Methods
The dataset used a revised two-leaf light use efficiency (TL-LUE) model with an added CO2 concentration regular scalar and the modified temperature scalar. These products are driven by the GLOBMAP leaf area index (GLOBMAP-LAI), Climatic Research Unit and Japanese reanalysis (CRUJRA 2.2) meteorological data, and European Space Agency Climate Change Initiative Land Cover (ESA-CCI) data.