RIAM-Chemical weather FORecasting System (CFORS)

RIAM-Chemical weather FORecasting System (CFORS)

Contact Information:

Gregory R. Carmichael
Department of Chemical & Biochemical Engineering
The University of Iowa
Iowa City, IA 52242
Telephone: (319) 225-1399
E-mail: gcarmich@icaen.uiowa.edu

Prof. Itsushi Uno and Mr. Koji Ishihara
Research Institute for Applied Mechanics
Kyushu Univ., Japan
E-mail: iuno@riam.kyushu-u.ac.jp

Model Description:

The University of Iowa and Kyushu University are developing and applying an operational Chemical weather FORecasting System (RIAM-CFORS) based on 3D on-line regional scale chemical transport model fully coupled with RAMS (Regional Atmospheric Modeling System).

The basic approach followed to study aerosol/chemical interactions is to utilize a regional-scale, process oriented model (i.e., STEM-II). The basic modeling approach, and processes considered are presented at http://www.cgrer.uiowa.edu/people/carmichael/ACESS/CTM_main.html . The model is designed as a flexible framework that can run in both on-line and off-line modes, and consists of a series of plug-and-play modules. The model can be run with meteorological inputs from MM5, RAMS, or objectively analyzed NCEP or ECMWF fields. The model includes a size-resolved inorganic aerosol module that considers aerosol dynamics, surface chemistry, and gas-to-particle exchange. The aerosol model calculates the aerosol composition of inorganic soluble species (sodium, potassium, calcium, magnesium, ammonium, sulfate, nitrate, and chloride) and the distribution of volatile species (ammonium, nitrate, carbonate, and chloride). The approach taken is to treat gas/particle exchange as a kinetic process under thermodynamic constraint. This aerosol module has been incorporated into the three-dimensional model (STEM-II), along with on-line dust and sea-salt aerosol emissions. More details regarding RIAM-CFORS may be found at: http://www.cgrer.uiowa.edu/people/carmichael/ACESS/index.html

The RIAM-CFORS system consists of several important components:

One of the main purposes of this system is to understand the regional transboundary pollution and to schedule/design the operational field monitoring campaign during the TRACE-P (TRAnsport and Chemical Evolution over the Pacific) and ACE-Asia (Aerosol Characterization Experiment - Asia) intensive observations. This system should be running until the end of April 2001. Results of daily operational forecasting and products will be posted around 0:00Z (9:00JST). Please note that this site is presented as is and no guarantee is made as to the timeliness or accuracy of the forecasting data. We reserve the right to take off-line this site at any time for any reason without warning.

CFORS-RAMS driver:
The parallel version of the RAMS(version 4.3.0) has been used to simulate the regional scale 3-D meteorological fields with Beowulf type Linux cluster (17 nodes). The simulation domain adopted is centered at 25N 115E. The horizontal grid consists of 100 by 90 grid points, with a resolution of 80 km. In the vertical, the domain is divided into 23 layers (top level is 20km).

CFORS-MIRACL Chemical Transport driver:
A tracer model is fully coupled with RAMS, and this is a unique approach because the regional meteorological conditions such as precipitation, cloud microphysics, diurnal cycle of boundary-layer turbulence play significant role in the wet deposition and vertical diffusion of tracers. The on-line tracer model runs with same time step as the RAMS, so that all the on-line meteorological information such as 3-D wind field, boundary-layer turbulence, surface fluxes and precipitation amount is directly used by the tracer model at every time step. At present, the CFORS system includes the following chemical transport species:

* indicates that concentration of this species decay as a first order reaction rate.

CFORS: Operational Time Charts:
Operational global forecast data set access to NCEP (National Center for Environmental Prediction) AVN data set and Japan Meteorological Agency (JMA) DDB data set are operationally ftped. See CFORS daily timing cycle chart.

CFORS:Post-processing options:
CFORS web manager supports the necessary post processing of the forecasting results both meteorological and chemical components. The 2/3D user friendly interface is prepared for easy use of this system.

Model Products and Output: http://dejima.riam.kyushu-u.ac.jp/~cfors/index.html
passwd=riamace (case sensitive !)