9 Water Vapor and Entropy Production in the Earth’s Atmosphere

Abstract

This chapter investigates the production of entropy by moist processes in the Earth’s climate system. The atmospheric circulation can be considered as a dehumidifier and heat engine operating in parallel: the dehumidification process reduces the system’s overall efficiency far below the Carnot limit. In idealized simulations, moist processes are found to be a much stronger source of entropy production than is frictional dissipation. These results are then discussed in the context of the Earth’s entropy production budget.