MIXED-LAYER CONVECTIVE TURBULENCE THEORY WITH FIRST INTERNATIONAL SATELLITE-LAND SURFACE CLIMATOLOGY PROJECT FIELD EXPERIMENT DATA

The convective turbulence theory (CTT) [Stull, 1994] has several advan tages over traditional bulk atmospheric boundary layer similarity form ulations for the surface momentum and sensible heat fluxes under free convection. In particular, in CTT surface fluxes at scales of 10(1)-10 (2) km are parameterized directly from surface and mixed layer measure ments, without regard to the surface layer profiles or surface roughne ss. The equations of CTT are tested with the First International Satel lite-Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE) data set; the theory is extended so that geostrophic winds may be use d in place of mixed layer winds; the formulation is applied to satelli te-derived surface temperature data; and Stull's [1994] mixed convecti on interpolation formula is tested. The scatter on graphs of the mixed layer transfer coefficients for momentum and sensible heat is greater for the FIFE data than for the Boundary-Layer Experiment 1983 (BLX83) data used by Stull [1994], and the mean coefficient values are greate r, probably because of the use of radiosonde data at FIFE and spatiall y averaged aircraft data at BLX83. Surface momentum and sensible heat flux estimated on the basis of CTT produced reasonable results but pro vided little or no improvement over a direct correlation between the r eference fluxes and the mixed layer wind speed or the surface-to-mixed layer temperature difference. The geostrophic version of CTT provided results comparable to the original CTT. Remotely sensed surface tempe ratures used with geostrophic CTT allowed reasonable estimates of the surface sensible heat flux.