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The particularities of the physics of the canopy layer pose challenges to the determination and use of traditional universal functions so helpful in the atmospheric surface layer. Progress toward "universal-like functions" such as those provided by Monin-Obukhov similarity theory for the canopy layer has been modest. One of the challenges lies in that the assumptions underlying Monin-Obukhov similarity theory do not hold within a canopy layer. This paper thus examines the local flux-profile relations for wind (&Phi;m) and for temperature (&Phi;h). It uses three different stability parameters, i.e., h/L(h) at tree top, local z/L(z), and the local bulk Richardson number (Ri), within a tall forest canopy in nighttime stable (indicated by h/L(h) > 0) conditions. Results suggest that the in-canopy &Phi;m can be described using the local Richardson number Ri. Furthermore, &Phi;m is found to increase linearly with Ri in the upper canopy layer for |Ri| < 1. When local |Ri| > 1, |&Phi;m| decreases with |Ri| in a power function, a result consistent for all levels of measurements within the canopy. When both local &Phi;h and local Ri are positive, i.e., the local downward turbulent heat flux is consistent with the local temperature gradient, the local &Phi;h increases with the local Ri when Ri < 1. However, &Phi;h does not change with Ri (or much more scattered) when Ri > 1. The relationship between local &Phi;h and Ri disappears when counter-gradient heat transfer occurs in strongly stable conditions. A self-correlation analysis is used to examine the influence of self-correlation and the physical meaning of these relationships

Local flux-profile relationships of wind speed and temperature in a canopy layer in atmospheric stable conditions