ABSTRACT

Improved representation of the spatial distribution and temporal development of surface latent (λE), sensible (H), and ground heat (G) fluxes is required not only to advance our understanding of important water and energy cycle processes but also to better describe the complex feedback mechanisms and interactions that occur between the land surface and the atmosphere. The latent heat flux provides the critical link between the water and energy cycles within the Earth system. Apart from enabling a description of water vapor exchanges for global water budget estimation, the accurate estimation of latent heat flux across a range of space-and timescales is needed in order to provide independent

CONTENTS

10.1 Introduction ........................................................................................................................ 249 10.2 Global Surface Heat Flux Estimation .............................................................................. 251

10.2.1 Evaporation Measurement: A Historical Context ............................................. 251 10.2.2 Descriptions of Models Used for Global Retrievals..........................................253