Abstract
Flux–profile relationships are crucial for parametrizing surface fluxes of momentum and heat, that are of central relevance for applications such as climate modelling and weather forecast. Nevertheless, their functional forms are still under discussion, and a generally accepted formulation does not exist yet. We reviewed the four main formulations proposed in the literature so far and assessed how they affect the theoretical behaviour of the kinematic heat flux (H0) and the temperature scale (T*) in the stable boundary layer, as well as their consequences on the existence of critical values for both the gradient and the flux Richardson numbers. None of them turned out to be fully consistent with the literature published so far, with two of them leading to very unreliable expressions for both H0 and T*. All considered, a convincing description of flux–profile relationships still needs to be found and seems to represents a considerable challenge.
Highlights
Layer—A Critical Discussion.Characterising the turbulent energy exchange between the atmosphere and the underlying surface is a central problem in boundary-layer research, especially under stable conditions, i.e., when turbulence is produced only by wind shear and tends to be suppressed by buoyancy
In this framework, following [1,4,6,11,12,13] and extending the analysis presented in [14], we systematically explored the consequences of adopting Monin–Obukhov similarity theory (MOST) under both weak and strong stability conditions, with particular reference to the behaviour of H0 and of the temperature scale T∗ when determined using four different universal similarity functions previously proposed in the literature
According to [34], under stable conditions the eddy covariance fluxes should be estimated over a few minutes, while longer integration times would result in inflating the stable boundary-layer (SBL) turbulence [35]
Summary
As highlighted in [22], MOST similarity relationship reliability increases when turbulent parameters are estimated over short time windows, mostly because nonturbulent motions are filtered out In this framework, following [1,4,6,11,12,13] and extending the analysis presented in [14], we systematically explored the consequences of adopting MOST under both weak and strong stability conditions, with particular reference to the behaviour of H0 and of the temperature scale T∗ when determined using four different universal similarity functions previously proposed in the literature (in both their gradient and bulk form). Since these functions are related to the gradient (Ri) and the flux Richardson number (R f ), consequences on the nonexistence of a critical value for Ri [23,24] are discussed
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
