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Anja Goldbach and Wilhelm Kuttler

. 2008 ; Granger and Hedstrom 2011 ), or combining flux gradient and model methods (e.g., Elo 2007 ). Furthermore, sensible heat flux can be measured directly using scintillometers, while latent heat flux has to be assessed indirectly if this method is used (e.g., McJannet et al. 2011 ; Bouin et al. 2012 ). However, it was possible to determine both heat fluxes directly using the eddy covariance (EC) technique. This method has already been established for various lake surfaces. One of the longest

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Jatin Kala, Mark Decker, Jean-François Exbrayat, Andy J. Pitman, Claire Carouge, Jason P. Evans, Gab Abramowitz, and David Mocko

-sided surface area of leaf per ground surface area. LAI is critical in any LSM since it affects the albedo of the terrestrial surface and hence the amount of net radiation available to drive sensible and latent heat. LAI also affects the partitioning of net radiation between sensible and latent heat fluxes ( Verstraete and Dickinson 1986 ) because it controls the surface area of vegetation in direct contact with the atmosphere and affects the efficiency by which water can be transferred from within the

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Xi Chen, Yongqin David Chen, and Zhicai Zhang

1. Introduction In the highly populated Huaihe River plain region in China ( Fig. 1 ), human activities, especially agriculture, influence the hydrological processes, and water resources management must focus on sustainability, tracked based on an accurate understanding of water distribution and fluxes. In other words, water storage in and movement among all dynamically linked reservoirs must be estimated in order to evaluate water availability caused by human impact. This task of modeling the

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William B. Bennett, Jingfeng Wang, and Rafael L. Bras

1. Introduction Ground heat flux (GHF), one of the main components of the land surface energy budget, is the dominant source of energy near the surface soil layer and is of primary importance to the ecosystem of the earth. GHF is comparable in magnitude to sensible and latent heat flux over relative dry soil at a diurnal time scale. The widely used Penman approach (e.g., Arya 1988 ) for the estimation of evaporation in land surface schemes of regional and global climatic models requires GHF

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Heping Liu, Qianyu Zhang, and Gordon Dowler

albedos (e.g., about 0.06 for open water and 0.08 for vegetated lands) ( Henderson-Sellers 1986 ; Bonan 1995 ). It is known that sensible heat flux H is primarily determined by the air temperature difference between the water surface and the overlying atmosphere as well as the turbulent exchange coefficient. Latent heat flux λE is dependent upon vapor pressure differences between the water–atmosphere interface and the overlying atmosphere as well as the turbulent mixing intensity ( Henderson

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F. Castellví and R. L. Snyder

and large areas of uniform fetch, which are uncommon in many grape production areas.” Because the surface renewal (SR) method may operate close to the canopy ( Paw U et al. 1995 , 2005 ), fetch requirements may be minimized, which makes it a useful micrometeorological method for small grape vineyards where fetch requirements limit the application of other methods. Spano et al. (2000) , Castellví et al. (2002) , and Castellví (2004) have used the SR method to estimate sensible heat flux H

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Wenhui Cui and Ting Fong May Chui

imbalance when the eddy covariance technique was applied over heterogeneous landscapes ( Foken et al. 2004 ; Foken 2008 ; Stoy et al. 2013 ). For instance, Kochendorfer and Paw U (2011) identified the role of atmospheric advection in the energy balance using a large array of eddy covariance systems. Higgins et al. (2013) introduced an analytical approach to explore the advection transport mechanism over a land–lake transition and calculated the lateral flux of water vapor in the atmosphere. The

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Eleanor Blyth, John Gash, Amanda Lloyd, Matthew Pryor, Graham P. Weedon, and Jim Shuttleworth

to rainfall or river runoff, there are no publicly available global evaporation data. However, relevant surface exchange data are becoming available through the flux network (FLUXNET; Baldocchi et al. 2001 ). Many medium-term (5–10 years), ground-based observations of carbon dioxide and surface energy fluxes are now being made by FLUXNET at a network of locations across the world in different climate zones and over different ecosystems. Therefore, FLUXNET is arguably the most comprehensive

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Shuwen Zhang, Bangjun Cao, Weidong Zhang, Qian Cao, Yuan Liu, and Chongjian Qiu

1. Introduction Accurate estimates of the surface turbulent heat fluxes have always been the central and practical concern in atmospheric science and hydrometeorology, because the fluxes characterize the mass and energy exchanges between the surface and the atmosphere aloft and have a profound impact on the upper airflow. Besides, accurate estimates of the surface heat fluxes are imperative for accurately validating modeling of surface energy and mass balances ( Kalma et al. 2008 ). The

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G. O. Odhiambo and M. J. Savage

1. Introduction The 1998 Republic of South Africa National Water Act ( Republic of South Africa 1998 ) suggests a possible prescription for water allocation and charges for different land uses, making it even more crucial to consider how evaporation, which is one of the main components of the water balance, is to be measured or estimated routinely with reliable accuracy and precision ( Savage 2009 ). Reliable estimation of energy fluxes from a surface is also important for understanding

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