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Sen Li, Zhong Zhong, Weidong Guo, and Wei Lu

1. Introduction The turbulent exchange process plays an important role in land–atmosphere interaction. Accurate representation of the eddy fluxes is essential for understanding the energy transfer in the land–atmosphere system and for successful numerical simulations of the atmosphere processes ( Lee 1997 ). Generally, the momentum and heat fluxes are estimated by the Bowen ratio energy balance (BREB) method ( Fritschen and Simpson 1989 ) and the profile method based on the Monin

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Hyun-Mi Oh, Kyung-Eak Kim, Kyung-Ja Ha, Larry Mahrt, and Jae-Seol Shim

1. Introduction More than 70% of the earth’s surface is covered with oceans. To understand the physical processes related to atmosphere–ocean interaction, flux measurements over the ocean are necessary. Because of insufficient direct observations of fluxes over the sea surface, air–sea fluxes in models have often been parameterized in terms of mean parameters and the bulk exchange coefficient. The parameterizations are based on the results of field experiments conducted over land and sea. While

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Shashi K. Gupta, David P. Kratz, Paul W. Stackhouse Jr., Anne C. Wilber, Taiping Zhang, and Victor E. Sothcott

) measurements of reflected and earth-emitted radiation in three broadband channels: a shortwave (SW) channel (0.2–5.0 μ m), a total channel (from 0.2 to >100 μ m), and a thermal infrared (IR) window channel (8–12 μ m). An extensive modeling effort is subsequently used with TOA measurements for deriving surface SW and longwave (LW) fluxes and corresponding flux profiles at multiple levels in the atmosphere. The three LW algorithms discussed in this study are part of the surface-only flux algorithms (SOFA

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Thara V. Prabha, Monique Y. Leclerc, Anandakumar Karipot, and David Y. Hollinger

1. Introduction Nocturnal respiratory release of carbon dioxide (CO 2 ) is an integral component of the ecosystem carbon balance. Several studies ( Goulden et al. 1996 ; Greco and Baldocchi 1996 ; Lindroth et al. 1998 ; Chen et al. 1999 ; Hollinger et al. 1999 ; Aubinet et al. 2000 ; Saleska et al. 2003 ) have reported an underestimation of CO 2 fluxes often associated with inadequate mixing in the stable boundary layer (SBL). Sporadic outbreaks of turbulence are also a common occurrence

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Carlos Domenech, Ernesto Lopez-Baeza, David P. Donovan, and Tobias Wehr

placed upon the retrieved cloud–aerosol profiles is consistent with a top-of-atmosphere (TOA) combined shortwave (SW) and longwave (LW) flux accuracy of 10 W m −2 for an instantaneous footprint of 10 × 10 km −2 ( EarthCARE Mission Advisory Group 2006 ). The scientific goals will be fulfilled by the payload of four instruments with precise collocated fields of view (FOV). The vertical atmospheric profiles will be acquired using a 353-nm high-spectral-resolution lidar (ATLID) and a cloud-profiling W

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Kun Yang, Jun Qin, Xiaofeng Guo, Degang Zhou, and Yaoming Ma

1. Introduction It is well recognized that the Tibetan Plateau (TP) provides an elevated heat source for the North Hemisphere ( Flohn 1957 ; Ye and Gao 1979 ), and this elevated heating drives the TP monsoon, enhances the Asian monsoon circulation, and significantly influences precipitation in China ( He et al. 1987 ; Yanai et al. 1992 ; Wu and Zhang 1998 ; Qian et al. 2004 ; Liu et al. 2007 ). The sensible heat flux is a major component of the TP heat source and has been addressed for

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Kun Yang, Toshio Koike, Hirohiko Ishikawa, Joon Kim, Xin Li, Huizhi Liu, Shaomin Liu, Yaoming Ma, and Jieming Wang

1. Introduction Turbulent flux near the earth’s surface is the key quantity for hydrometeorological modeling of land–atmosphere interactions and remote sensing of water resources. Aerodynamic and thermal roughness lengths are the two crucial parameters for bulk transfer equations to calculate turbulent flux. They are defined so that a surface nonslip condition and surface skin temperature can be applied within the framework of Monin– Obukhov similarity theory. The aerodynamic roughness length

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S. W. Hoch, P. Calanca, R. Philipona, and A. Ohmura

1. Introduction The divergence of the longwave radiative fluxes is an important component of the thermodynamics of the atmospheric boundary layer ( Kondratyev 1969 ; Garratt and Brost 1981 ). The cooling associated with the divergence of longwave radiation is understood to be essential for the establishment and maintenance of persistent surface inversion layers close to the surface during the polar night ( Cerni and Parish 1984 ). Over large ice sheets, the strong radiative cooling has been

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David P. Kratz, Paul W. Stackhouse Jr., Shashi K. Gupta, Anne C. Wilber, Parnchai Sawaengphokhai, and Greg R. McGarragh

1. Introduction Defining the radiative energy exchange at the top of the earth–atmosphere system and at the earth’s surface has long been identified as critical to understanding climate processes ( Suttles and Ohring 1986 ; GCOS 2003 ) and remains an active focus of research ( Stephens et al. 2012 ; Wild et al. 2013 ). The reflected shortwave (SW) and outgoing longwave (LW) fluxes at the top of the atmosphere (TOA) constitute the radiative energy exchange of the entire earth–atmosphere system

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Yingtao Ma, Rachel T. Pinker, Margaret M. Wonsick, Chuan Li, and Laura M. Hinkelman

1. Introduction a. Background Snow-covered mountain ranges are a major source of water supply for runoff and groundwater recharge. Snowmelt supplies as much as 75% of the surface water in basins of the western United States ( Beniston 2006 ). Factors that affect the rate of snowmelt include incoming shortwave (SW) and longwave radiation; surface albedo; snow emissivity and temperature; sensible, latent, and ground heat fluxes; and energy transferred to the snowpack from deposited snow or rain

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