Comparison between IMPACT ans Newthon-Raphson Solver
N-R (method=3): In Feb. 2015, the solver was changes such that individual air parcels will be checked for convergence criteria, and not further iterated. This gives about Factor 3.5 gain in computing time for this example.
N-R (method=3) was tested against IMPACT (method=1) in Feb. 2015 with no significant changes in the output (zonal mean values).
Performance of the Newthon-Raphson Solver depends on how consistent the initial chemical composition is. In the case of non consistent initialisation the decrease of timestep (having) is freqently needed with the cause of significant longer integration times. Especially for the global run (T14) upon initialisation the difference in computing time is factor 3.8