The diagnosis of mechanical dissipation in the atmosphere from large- scale balance requirements

Abstract

The balance requirement does not support the high parameterized values of orographically induced gravity-wave drag in the lower stratosphere. A deeper analysis also does not suggest a major role for turbulent vertical transports above the boundary layer. On the other hand, our budget does indicate that more effort be spent on a better representation of the potential enstrophy cascade associated with Rossby wave breaking in the upper troposphere. These statements are qualified by the errors in the balance requirement itself. The extent to which this is a problem is discussed. A distinctive feature of these calculations is their internal consistency; that is, all the terms in the budget are evaluated as in the version of the ECMWF model used for assimilating the observations. -from Authors