In:
Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 22, No. 1 ( 2022-01-10), p. 319-333
Abstract:
Abstract. An intercomparison between 10 single-column (SCM) and 5 large-eddy
simulation (LES) models is presented for a radiation fog case study
inspired by the Local and
Non-local Fog Experiment (LANFEX) field campaign. Seven of the SCMs represent
single-column equivalents of operational numerical weather
prediction (NWP) models, whilst three are research-grade SCMs designed
for fog simulation, and the LESs are designed to reproduce in the
best manner currently possible the underlying physical processes
governing fog formation. The LES model results are of variable
quality and do not provide a consistent baseline against which to
compare the NWP models, particularly under high aerosol or cloud
droplet number concentration (CDNC) conditions. The main SCM bias
appears to be toward the overdevelopment of fog, i.e. fog which is too
thick, although the inter-model variability is large. In reality
there is a subtle balance between water lost to the surface and
water condensed into fog, and the ability of a model to accurately
simulate this process strongly determines the quality of its
forecast. Some NWP SCMs do not represent fundamental components of
this process (e.g. cloud droplet sedimentation) and therefore are
naturally hampered in their ability to deliver accurate
simulations. Finally, we show that modelled fog development is as
sensitive to the shape of the cloud droplet size distribution, a
rarely studied or modified part of the microphysical
parameterisation, as it is to the underlying aerosol or CDNC.
Type of Medium:
Online Resource
ISSN:
1680-7324
DOI:
10.5194/acp-22-319-2022
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2022
detail.hit.zdb_id:
2092549-9
detail.hit.zdb_id:
2069847-1
Bookmarklink