Lorenz energy cycle of the global atmosphere based on reanalysis datasets

The mean state of the global atmospheric energy cycle is re-examined using the two reanalysis datasets - NCEP2 and ERA40 (1979-2001). The general consistency between the two datasets suggests that the present estimates of the energy cycle are probably the most reliable ones. The comparison between the present and a previous study shows noticeable discrepancies in some of the energy components and conversion rates. The current estimate of the transformations from mean potential energy to mean kinetic energy C(P-M, K-M) further suggests that the near-surface processes play an important role in the conversion rate C(P-M, K-M), along with the Ferrel cell and Hadley cells, which probably change the direction of the conversion rate C(P-M, K-M).