IOWA(Carmichael)

 

-STEM Tracer Model:

The Sulfur Transport and dEpostion Model (STEM) a comprehensive 3-dimensional regional scale model provides non-reactive tracer calculations. All the aerosols are treated as externally mixed in STEM-2k1 tracer model. The tracer model employs simple decaying rates for most primary species, plus wet scavenging and dry deposition. The dry deposition of aerosols was modeled using the eResistance in Series Parameterizationf@ Wet deposition of aerosols was calculated as a loss rate based on precipitation rate obtained from the meteorology model (e.g. MM5, WRF).

 

STEM full chemistry model:

STEM was developed at the University of Iowa in the early 1980s (Carmichael et al., 1986) and has continuously undergone development since then to its current version which is the STEM–2K3 version (Tang et al., 2007). STEM is a regional chemical transport model which features the SAPRC–99 chemical mechanism. Online photolysis rate calculations in the STEM are performed using the TUV (Tropospheric Ultra–Violet Radiation) model. The TUV model needs total ozone column to calculate the absorption of UV radiation by ozone molecules. Thirty different photolysis rates are calculated using the STEM–TUV model. The STEM uses the SCAPE II (Simulating Composition of Atmospheric Particles in Equilibrium Aerosol Solver) aerosol module to simulate inorganic gas to particle conversion and aerosol particle growth (Kim et al., 1995). The inorganic aerosols in the STEM–SCAPE model are binned into four size bins of 0.1–0.3µm, 0.3–1.0µm, 1.0–2.5µm and 2.5–10.0µm.

 

Optimal Interpolation:

The uncertainty in the model predictions can be reduced by integrating the observations into the model via data assimilation methods. Our recent work has shown that the model predictions over Asia were significantly improved by integrating the AOD observations using the Optimal Interpolation assimilation technique (Adhikary et al., 2008, Carmichael et al., 2009, Chung et al., 2010).

 

Also running Wrf/Chem for various Asia domains.

 

 

For the 2001- 2005 model simulations we have used 2000 TRACE-P anthropogenic emissions inventory and GFED biomass burning emissions

For 2006 model simulations we have used the 2006 INTEX-B emission inventory over Asia along with real time biomass emissions from the RAQMS model

For 2008 model simulations we have the 2008 ARCTAS emissions inventory along with the real time biomass emissions from the RAQMS model

 

 

Adhikary B., Carmichael G. R., Tang Y., Leung L. R., Qian Y., Schauer J. J., Stone E. A., Ramanathan V. and Ramana M. V. (2007). "Characterization of the seasonal cycle of south Asian aerosols: A regional-scale modeling analysis." Journal of Geophysical Research, [Atmospheres] 112(D22).

Adhikary, B.; Kulkarni, S.; Dallura, A.; Tang, Y.; Chai, T.; Leung, L. R.; Qian, Y.; Chung, C. E.; Ramanathan, V.; Carmichael, G. R. A regional scale chemical transport modeling of Asian aerosols with data assimilation of AOD observations using optimal interpolation technique. Atmos. Environ. 42, 8600-8615, 2008.

Adhikary, B., Carmichael, G. R., Kulkarni, S., Wei, C., Tang, Y., D'Allura, A., Mena-Carrasco, M., Streets, D. G., Zhang, Q., Pierce, R. B., Al-Saadi, J. A., Emmons, L. K., Pfister, G. G., Avery, M. A., Barrick, J. D., Blake, D. R., Brune, W. H., Cohen, R. C., Dibb, J. E., Fried, A., Heikes, B. G., Huey, L. G., O'Sullivan, D. W., Sachse, G. W., Shetter, R. E., Singh, H. B., Campos, T. L., Cantrell, C. A., Flocke, F. M., Dunlea, E. J., Jimenez, J. L., Weinheimer, A. J., Crounse, J. D., Wennberg, P. O., Schauer, J. J., Stone, E. A., Jaffe, D. A., and Reidmiller, D. R. (2010). "A regional scale modeling analysis of aerosol and trace gas distributions over the eastern Pacific during the INTEX-B field campaign." Atmos. Chem. Phys. 10(5): 2091-2115.

Carmichael, G.R., B. Adhikary, S. Kulkarni, A. DfAllura, Y. Tang, D. Streets, Q. Zhang, T.C. Bond, V. Ramanathan, A. Jamroensan, P. Marrapu, Asian Aerosols:@ Current and Year 2030 distributions and implications to human health and regional climate change, Env Sci. Tech., 43, 5811 -5817, 2009

Chung, C-E, V. Ramanathan, G. Carmichael, Y. Tang, B. Adhikary, L. R. Leung and Y. Qian, Anthropogenic aerosol radiative forcing in Asia derived from regional models with atmospheric and aerosol data assimilation, Atmos. Chem, Phys.,@ 2010.

 

1.     Gregory R. Carmichael

University of Iowa, USA

gcarmich<at>engineering.uiowa.edu