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Parameterization of turbulent flux from bare-soil and undercanopy surfaces is imperative for modeling land–atmosphere interactions in arid and semiarid regions, where flux from the ground is dominant or comparable to canopy-sourced flux. This paper presents the major characteristics of turbulent flux transfers over seven bare-soil surfaces. These sites are located in arid, semiarid, and semihumid regions in Asia and represent a variety of conditions for aerodynamic roughness length (z 0 m; from< 1 to 10 mm) and sensible heat flux (from− 50 to 400 W m− 2). For each site, parameter kB− 1 [= ln (z 0 m/z 0 h), where z 0 h is the thermal roughness length] exhibits clear diurnal variations with higher values during the day and lower values at night. Mean values of z 0 h for the individual sites do not change significantly with z 0 m, resulting in kB− 1 increasing with z 0 m, and thus the momentum transfer coefficient …