The impact of resolution on ship plume simulations with NOx chemistry 1Institute for Climate and Atmospheric Science, School of Earth and Environment, University of Leeds, Leeds, UK
2Department of Mathematics, University College London, London, UK
Received: 25 January 2009 – Published in Atmos. Chem. Phys. Discuss.: 31 March 2009 Abstract. A high resolution chemical transport model of the marine boundary
layer is designed in order to investigate the detailed chemical
evolution of a ship plume in a tropical location.
To estimate systematic errors due to finite model
resolution, otherwise identical simulations are run at a
range of model resolutions. Notably, to obtain comparable plumes in the
different simulations, it is found necessary
to use an advection scheme consistent with the
Large Eddy Model representation of sub-grid winds for those simulations with
degraded resolution. Our simulations show that OH concentration,
NOx lifetime and ozone production efficiency of the model change by 8%,
32% and 31% respectively between the highest
(200 m×200 m×40 m)
and lowest resolution
(9600 m×9600 m×1920 m) simulations.
Interpolating to the resolution of a typical
global composition transport model (CTM, 5°×5°), suggests
that a CTM overestimates OH, NOx lifetime and ozone production efficiency
by approximately 15%, 55% and 59% respectively.
For the first time, by explicitly degrading the model spatial resolution we show that
there is a significant reduction in model skill in accurately simulating
the aforementioned quantities due to the coarse resolution
of these CTMs and the non-linear nature of atmospheric chemistry.
These results are significant for the assessment and forecasting of the
climate impact of ship NOx and indicate that
for realistic representation of ship plume emissions in CTMs,
some suitable parametrisation is necessary at current global
Revised: 28 July 2009 – Accepted: 31 July 2009 – Published: 09 October 2009
Citation: Charlton-Perez, C. L., Evans, M. J., Marsham, J. H., and Esler, J. G.: The impact of resolution on ship plume simulations with NOx chemistry, Atmos. Chem. Phys., 9, 7505-7518, doi:10.5194/acp-9-7505-2009, 2009.