Abstract
MarsWRF, the general circulation model of Mars, is one of the most
commonly used models to study the dust cycle in the Martian atmosphere.
It has been widely used to study the mechanisms of dust storms and their
effects on the Martian atmosphere. To better understand the ability of
MarsWRF to simulate the dust cycle on Mars, this study assesses the
current dust lifting schemes in the model, specifically the convective
lifting and wind stress schemes. It is found that, by tuning lifting
efficiency, the model with the convective lifting scheme can generally
reproduce the seasonal variation of the mid-level atmospheric
temperature (T15) but cannot reproduce the observed spatial distribution
of dust devils, which exhibits non-homogeneous (uniform) distribution in
the northern (southern) hemisphere. The model with the wind stress
lifting scheme can generally capture the observed magnitude of T15 and
column dust optical depth (CDOD) with properly tuned lifting efficiency
and threshold drag velocity. There is a discrepancy in the assessment of
modeling seasonal variations of dust with T15 and CDOD, which may be
partly due to the observational uncertainties related to T15 and CDOD
and the empirical modeling methods of Martian dust optical properties
and radiative effect. For the spatial distribution of dust, there are
significant simulation biases regardless of the tuning, which may be
caused by the biases in the dust lifting process and large-scale
atmospheric circulation. The analysis highlights that dust lifting
schemes need further improvement to better represent the dust cycle and
their impacts on Mars.