Global 3-D Simulations of the Triple Oxygen Isotope Signature ΔO in Atmospheric CO.

The triple oxygen isotope signature ΔO in atmospheric CO, also known as its "O excess," has been proposed as a tracer for gross primary production (the gross uptake of CO by vegetation through photosynthesis). We present the first global 3-D model simulations for ΔO in atmospheric CO together with a detailed model description and sensitivity analyses. In our 3-D model framework we include the stratospheric source of ΔO in CO and the surface sinks from vegetation, soils, ocean, biomass burning, and fossil fuel combustion.