Ensemble trajectories and uncertainty assessment
Posted: July 28th, 2023, 1:37 am
I am working on estimating the degree that aerosols encountered clouds along their back trajectories. Because it is near ground sampling, I am setting the initial height to be 0.1 * PBL height (~60-120 m). 27 ensemble trajectories were used to account for uncertainties. The default offset in z dimension in HYSPLIT is 0.01 sigma units (~250 m). In this case, is it better to increase the initial height to be 250 m, or to use a smaller offset factor (e.g. 0.005 or 0.0025) so that the vertical deviation is smaller than the starting height? Not sure what offset should be used for uncertainty analysis.
Additionally, I think the ensemble analysis only accounts for the error due to limited resolution of the meteorological data. I wonder how does this error compared with the error associated with trajectory integration - which error is more significant? Are there any other sources of error that one should consider in error estimation? Thank you!
Additionally, I think the ensemble analysis only accounts for the error due to limited resolution of the meteorological data. I wonder how does this error compared with the error associated with trajectory integration - which error is more significant? Are there any other sources of error that one should consider in error estimation? Thank you!