About GMI

What is GMI?

The Global Modeling Initiative (GMI) is a project that develops and maintains a modular 3D chemistry and transport model (CTM) that can be used for assessment of the impact of various natural and anthropogenic perturbations on atmospheric composition and chemistry. The GMI CTM was developed in the 1990s under the auspices of the NASA Atmospheric Effects of Aviation Project (AEAP). Its first application was the assessment of the impact of a fleet of high-speed civil transports on the abundances of stratospheric ozone, total inorganic nitrogen, and H2O [Kinnison et al., 2001].

The GMI model serves as a testbed for different model inputs. The modular framework of the GMI CTM, described in Rotman et al. [2001], offers the ability to incorporate different components and inputs, such as meteorological fields, chemical and microphysical mechanisms, source gas emissions, deposition schemes, and other processes determining atmospheric composition. It is compliant with the Earth System Modeling Framework (ESMF), thus facilitating incorporation of new model components. GMI can be used as a tool to expand parameter space in sensitivity studies and test parameterizations in general circulation models (GCMs). GMI seeks to understand and constrain the uncertainties in model results through intercomparison of simulations and testing with observations. Evaluating GMI results against observations is a high priority [Douglass et al., 1999; Strahan et al., 2016]. The GMI model can currently be compiled with 4 chemical mechanisms: troposphere-stratosphere, aerosol, coupled troposphere-stratosphere-aerosol, and a tracer suite (for process diagnostics).

The goals of the GMI effort are to:

  • reduce uncertainties in model results and predictions by understanding the processes that contribute most to the variability of model results, and by evaluation of model results against existing observations of atmospheric composition,
  • understand the coupling between atmospheric composition and climate through coordination with climate models, and
  • contribute to the assessment of the anthropogenic perturbations to the Earth system.

next: Who Uses GMI?

 

References

Douglass, A.R., M.J. Prather, T.M. Hall, S.E. Strahan, P.J. Rasch, L.C. Sparling, L. Coy, and J.M. Rodriguez (1999), Choosing meteorological input for the global modeling initiative assessment of high-speed aircraft, J. Geophys. Res., 104, 27,545-27,564.

Kinnison, D.E., P. S. Connell, J. M. Rodriguez, D. A. Rotman, D. B. Considine, J. Tannahill, R. Ramaroson, P. J. Rasch, A. R. Douglass, S. L. Baughcum, L. Coy, D. W. Waugh, S. R. Kawa, and M. J. Prather (2001), The Global Modeling Initiative Assessment Model: Application to High-Speed Civil Transport Perturbation, J. Geophys. Res., 106, 1693-1711.

Rotman, D.A.,  J.R. Tannahill, D.E. Kinnison, P.S. Connell, D. Bergmann, D. Proctor, J.M. Rodriguez, S.J. Lin, R.B. Rood, M.J. Prather, P.J. Rasch, D.B. Considine, R. Ramaroson, S.R. Kawa (2001), The Global Modeling Initiative assessment model: Model description, integration and testing of the transport shell, J. Geophys. Res., 106, 1669-1691.

Strahan, S.E., A.R. Douglass, S.D. Steenrod (2016) Chemical and dynamical impacts of stratospheric sudden warmings on Arctic ozone variability, J. Geophys. Res., 19, 11836-11851.