deletions | additions       diff --git a/TCCON_not_only_provides_validation__.tex b/TCCON_not_only_provides_validation__.tex  index 9383d89..3aa2e1f 100644  --- a/TCCON_not_only_provides_validation__.tex  +++ b/TCCON_not_only_provides_validation__.tex 
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TCCON not only provides validation for a number of satellite missions, but can also contribute to understanding of carbon cycle science, typically via use in conjunction with atmospheric chemical transport models. For example, TCCON CO$_2$ data revealed an underestimate in the seasonal cycle of net ecosystem exchange (NEE) in an earlier version of the CASA biosphere model \cite{Yang_2007}. More recently, \citet{Wunch_2013} showed a robust relationship between boreal surface temperature anomalies and the magnitude of summer CO$_2$ drawdown in the northern hemisphere columns; the strength of that relationship is underestimated when using biospheric models or the CarbonTracker data assimilation system. In including TCCON X$_{CO_2}$ data in an inversion, \cite{Chevallier_2011} \citet{Chevallier_2011}  highlighted that Australia is a region where total column observations have greater power than surface in situ measurements to provide constraints on surface flux estimates.