A New Mass Flux Correction Procedure for Vertically Integrated Energy Transport by Constraining Mass, Energy, and Water Budgets.

Reconstruction of the atmospheric circulation from the numerical output of general circulation model (GCM) and reanalysis products often suffers from spurious values resulting in imbalances in the mass, energy, and water transport. A correction hence is needed prior to the analysis of energy transport. Most of the previous correction methods only employ a mass budget adjustment since it is the primary source of error. The present study proposes a new method of mass flux correction by constraining the mass, energy, and water budgets that can be applied to meridional energy transport and overturning circulation. The new method seeks a vertical dependent solution, unlike the conventional barotropic correction procedures. The procedure has been tested for one aquaplanet GCM and a reanalysis product. The method successfully corrects the spurious imbalances in the mean meridional energy transport and circulation. Plain Language Summary: Meridional energy transport is an essential climate diagnostic. However, the calculation of energy transport from climate model output and reanalyses often encounters spurious values due to mass, energy, and water budget imbalances. Although climate models are based on fundamental conservation laws, the numerical models often slightly deviate due to various interpolations, approximations, and low resolution. Traditionally, such imbalances are corrected by adjusting the mass flux to satisfy mass conservation, which corrects the spurious values in energy transport to a certain extent. The present paper proposes a new mass flux correction method that satisfies not only the mass conservation but also the energy and water conservation. Unlike the conventional vertically uniform correction, the present method provides a vertically dependent correction. Moreover, the new mass flux correction can also be applied to correct the mean meridional circulation. The result demonstrates that the new method is a remarkable improvement from the conventional methods. Key Points: The present study proposes a new flux correction method for vertically integrated zonal mean energy transport in the atmosphereThe proposed method satisfies the conservation of mass, energy, and water vapor, which was not a characteristic of most previous methodsUnlike the previous methods, the new approach provides a vertical dependent correction [ABSTRACT FROM AUTHOR]