photo: G. H.

Investigation of Turbulence Structures in the

Stable Stratified Boundary Layerwith the LM

Marc Krebsbach and Günther Heinemann

turbulence closure schemes in the LM simulations summary

turbulence closure schemes in the LMdiagnostic scheme prognostic scheme

Mellor, G. L. and T. Yamada: 1982, ‘Development of a Turbulence Closure Model for Geophy-sical Fluid Problems‘. Rev. Geophys. Space Phys. 20(4), 851–875

Müller, E.: 1981, ‘Turbulent flux parameterisation in a regional scale model‘. ECMWF workshop proceedings, 25.–27. November, 193–220

23 2212 NKMKle hm

‘level 2’ (Mellor & Yamada, 1982)

223

221 RiRiRiR f

solutions in terms of

modified procedure after Müller (1981)

with

z

z

1

more terms

vertical diffusion of TKE

expanded solution under stable conditions

additional item: circulation term

closure order 1.5 with prog. TKE

simulations

Greenland map

model area around Kangerlussuaq

Pa Pb 100 km

simulationsdiagnostic scheme prognostic scheme

grid point

heig

ht A

GL

in

m

simulationsdiagnostic scheme

grid point

height AG

L in mhe

ight

AG

L in

m

simulationsprognostic scheme

heig

ht A

GL

in

mheight A

GL

in m

grid point

summary

LM is able to simulate complex flow structures in tundra region different reaction to variations of closure length

mean quantities: accurate for diagnostic scheme, some disadvantages in the lowest 100 m AGL

turbulent quantities: clear advantage of the prognostic scheme

no pattern length scale in the investigated SBL closure length has to be adapted to the SBL

turbulent fluxes: max. ; mean o.k.

successful simulation of a hydraulic jumpOBSLM FF 2