ABSTRACT

The Monin-Obukhov similarity theory (MOST) has been the theoretical foundation for understanding the atmospheric surface layer since its inception. However, it has been known since the late 1950s that a number of important surface layer statistics do not conform to MOST. Since the early 1970s much effort has been devoted to resolving this issue. In 2015 we proposed a revised theory, the multipoint Monin-Obukhov similarity theory (MMO), which overcomes the major limitations of MOST. It hypothesizes that the surface layer turbulence possesses complete similarity, but only represented by mutipoint statistics. Using the new physical insights gained from the AHATS field campaign, the theory further identifies the Obukhov length as a horizontal characteristic length scale, which is absent in MOST. More recently, we have derived MMO from first principles using the Navier Stokes and potential temperature equations for the case of the horizontal Fourier transforms of the velocity and potential temperature. Using MMO we have derived the turbulence spectra, cospectra, and the mean velocity and temperature profiles. MMO provides a new framework for understanding and investigating the atmospheric boundary layer, and has implications for a range of applications where the surface layer turbulence plays an important role.