Modeling Tools & Applications

iChamber

*** NEW: a Python-based model is currently under development! The python-based model is ~10x faster than the Igor-based model because I'm supplying the Jacobian matrix. It also works on supercomputers. If you're interested, shoot me an email! ***

~ Summary ~

    • Based on IGOR Pro, with a built-in graphical user interface (GUI). Can handle very stiff ODE problems.

    • Support Kinetic PreProcessor (KPP). e.g. KPP format generated from the MCM website.

    • Templates for explicit phase-transfer, aqueous-phase chemistry, heterogeneous chemistry provided.

    • Can couple with external FORTRAN modules, e.g. ISORROPIA.

    • Evaluated with FACSIMILE and chamber data. Ideal for chamber, flow tube/reactor studies and well-defined ambient problems.

    • Also great for teaching / educational purposes.

    • A step-by-step tutorial is currently underdevelopment; basic modeling skills are demonstrated via a number of interesting research topics.

    • Freely available on my website.

~ Publications using my 0-D Box Model ~

    • McNamara et al. (2020) ACS Earth Space Chem. Link

    • S.-Y. Wang et al. (2019) Proc. Natl. Acad. Sci. U.S.A. Link

    • S.-Y. Wang et al. (2019) Geophys. Res. Lett. Link

    • S.-Y. Wang and Pratt. (2017) J. Geophys. Res. - Atmos. Link

    • S.-Y. Wang et al. (2015) Proc. Natl. Acad. Sci. U.S.A. Link

    • T. Koenig et al. (2016) Atmos. Chem. Phys. Link

    • S. Coburn et al. (2016) Atmos. Chem. Phys. Link

    • B. Dix et al. (2013) Proc. Natl. Acad. Sci. U.S.A. Link

    • S.-Y. Wang et al. (2013) J. Geophys. Res. - Atmos. Link

~ Publications using the 1-D Model ~

    • McNamara et al. (2020) ACS Central Science. Link

    • S.-Y. Wang et al. (2020) ACS Earth Space Chem. Link

~ Other application ~

  • iChamber has a graphic user interface (GUI): for quick settings & browse modeling results.

  • Easy to design hands-on experiments. Great for teaching / educational purposes!

  • Several post-processing tools are provided.

  • Chemical mechanism: can directly load KPP format. Alternatively, users can manually "type" in conventional format.

  • If constant rate coefficients are used, then the model can be "code-free": No need to touch the source codes!

  • Demo: chamber study of OH oxidation of isoprene under high NOx condition (Paulot et al Atmos. Chem. Phys. 2009).

  • Multiple chemical mechanisms are tested using the box-model, including MCM v3.3.1, MOZART T1 (Emmons et al., 2020), and an updated T1 with new BVOCs chemistry (Schwantes et al. 2020)

  • Demo: chamber study of OH oxidation of isoprene under low NOx condition (Paulot et al. Science 2009).

  • Modeled using MCM v.3.3.1.

  • Chemical evolution of ambient forest air (isoprene, monoterpenes, aromatics) after 8 days, modeled using MCM v3.3.1. Initial condition: Hunter et al. Nature Geoscience 2017.

  • Each bubble is one chemical compound. Size represents concentration on a carbon basis (μgC/m3), color-coded by chemical lifetime.

  • Special application: 1-dimensional multi-phase photochemical model.

  • Initially developed by Siyuan Wang, partially supported by National Science Foundation OPP-1417668 (PI: Kerri Pratt; co-PI: Roland von Glasow).

  • Jointly developed with Angela Raso (Purdue), Peter Peterson (UMich/WhittierCollege), Sham Thanekar (PennState), Jose Fuentes (PennState), Paul Shepson (Purdue).

  • Projects and publications:

McNamara et al. (2020) ACS Central Science. LinkS.-Y. Wang et al. (2020) ACS Earth Space Chem. Link


~ TUTORIAL ~

~ A portal to an ancient ruin, in which buries the very first version of the model ~