Higher-order mean velocity profile in the convective atmospheric boundary layer*

The mean velocity profile in the surface layer of the atmospheric boundary layer is generally considered to follow the Monin-Obukhov similarity, a leading-order theory. It is well known that measured mean profiles show scatters that cannot be explained by uncertainties. We derive the higher-order mean velocity profile using the Multipoint Monin-Obukhov Similarity Theory, which includes additional parameters to account for the deviation from the Monin-Obukhov Similarity function. The relevant equations form a singular perturbation problem. An approximate solution is obtained using the method of matched asymptotic expansions. To obtain the coefficients in the higher-order terms, we conducted a field campaign, Multipoint Monin-Obukhov Horizontal ArrayTurbulence Studies (M2HATS) in the summer/fall of 2023 in Tonopah NV. Sonic anemometers on a tower and two Doppler lidars were deployed to obtain the mean profile up to an approximately 2 km height. Preliminary comparisons between the measurement results and the theoretical prediction will be presented.