Comment on "Contrasting carbon cycle responses of the tropical continents to the 2015-2016 El Niño".

Liu et al (Research Articles, 13 October 2017) inferred carbon flux anomalies in tropical continents with enough confidence to constrain the driving carbon-exchange processes. I show that they underestimated their error budget and that more effort must be invested in the satellite concentration retrievals and in the atmospheric transport models before such precision can be achieved.