Fog prediction for
the New York area in support to the Northeast Ceiling and Visibility
Initiative.
The main objective of
this project is to improve & evaluate the high resolution 1D
(column) numerical modeling approach for the fog prediction problem in
a complex environment.
The accurate
representation of the vertical structure of the lower atmosphere during
the evening transition, and later on in the stably stratified nocturnal
boundary layer, requires a high vertical resolution since sharp
vertical gradients usually characterize the temperature, humidity and
wind profiles in lower part of the atmosphere during that time. The
onset of fog and subsequent characteristics depend sensitively on
the evolution of the lower atmospheric profiles during the evening
transition. Therefore, the use of a high-resolution boundary layer
model is necessary for short-term numerical forecasts of fog.
As
preliminary explorations into the numerical simulation of fog,
numerical experiments were performed with the COBEL model. For
instance, an investigation of the sensitivity of the dew/frost
deposition process to environmental conditions was conducted:
Another series of COBEL simulations was performed once the SBDART
radiative transfer scheme was implemented in order to study the
possible impact of aerosols on the evening transition of the boundary
layer:
Some simulations were also performed to assess the sensitivity of
marine fog formation to variations in sea surface temperature typical
of the coastal areas of the northeastern United States:
The COBEL model was also used to carry out an investigation of the
effect of vertical resolution on the short-term forecast of a radiation
fog event:
more to come...
These efforts are part
of the National Ceiling and Visibility project, funded by the Federal
Aviation Administration (FAA) Aviation Weather Research Program
(AWRP).
* The
views expressed here are those of the author of this web page and do
not necessarily represent the views of the FAA.
