Some of that CO2 rise is attributable to data fraud.
The short seasonal dip at Barrow is due to the short growing season. The data matches up with the known facts about CO2 production from fossil fuel burning, cement making and deforestation reducing natural uptake. There are plenty of unknowns like ocean uptake variations (e.g the 2016 El Nino is clearly visible), but there are few unknown unknowns. Some people claim volcanic activity creates the rise, but it can't create that rise. There is no "fraud" in the graph above, it is what it is.