Guo, Zhichang, Paul A Dirmeyer, Randal D Koster, Gordon Bonan, Edmond Chan, Peter Cox, C Tony Gordon, Shinjiro Kanae, Eva Kowalczyk, David Lawrence, P Liu, Cheng-Hsuan Lu, Sergey Malyshev, B McAveney, J L McGregor, K Mitchell, D Mocko, T Oki, K W Oleson, A J Pitman, Y C Sud, C M Taylor, D Verseghy, R Vasic, Y Xue, and T Yamada, 2006: GLACE: The Global Land–Atmosphere Coupling Experiment. Part II: Analysis. Journal of Hydrometeorology, 7(4), DOI:10.1175/JHM511.1. Abstract
The 12 weather and climate models participating in the Global Land–Atmosphere Coupling Experiment
(GLACE) show both a wide variation in the strength of land–atmosphere coupling and some intriguing
commonalities. In this paper, the causes of variations in coupling strength—both the geographic variations
within a given model and the model-to-model differences—are addressed. The ability of soil moisture to
affect precipitation is examined in two stages, namely, the ability of the soil moisture to affect evaporation,
and the ability of evaporation to affect precipitation. Most of the differences between the models and within
a given model are found to be associated with the first stage—an evaporation rate that varies strongly and
consistently with soil moisture tends to lead to a higher coupling strength. The first-stage differences reflect
identifiable differences in model parameterization and model climate. Intermodel differences in the evaporation–
precipitation connection, however, also play a key role.
