the warning "Puff splitting turned off. Increase MaxPar" means that the puffs are not able to split anymore
because you have MaxPar puffs. Puff splitting is a bit hard to predict as it will depend on meteorological conditions.
I don't understand what you are saying about mass conservation or how you are calculating it. Please give more explanation on what
you mean by:
To compare, I grid each dispersion and compare the corresponding grid cells between the dispersions. However, when I sum the grid cells in each model, I get drastically different values, indicating that mass isn't always conserved.
Are you looking at the concentration grid output (cdump) files?
Each particle / puff carries a certain amount of mass. This mass will stay the same unless you have wet and/or dry
deposition turned on. When the puff splits, the amount of mass will be split as well.
Please look at the MESSAGE files or attach them here.
They have information about the number of particles / puffs and the amount of mass in the rightmost columns.
See example of part of a MESSAGE file below.
The particle number starts at 252 and ends at 5040. The amount of mass starts at 0.2 and ends at 4.0.
NOTICE metinp: GDAS 1 1 10 10 181 139 57119040 8 8 8 0
NOTICE advrng: (kg ,xyr,xy1) - 1 10 10 181 139
NOTICE main: Initial time step (min) 3
NOTICE emspnt: emissions started
NOTICE main: 1 57118923
252 0.20000000
NOTICE main: 1 57118926 504 0.40000281
NOTICE main: 1 57118929 756 0.60000277
NOTICE main: 1 57118932 1008 0.79999900
NOTICE main: 1 57118935 1260 0.99999523
NOTICE main: 1 57118938 1512 1.2000065
NOTICE main: 1 57118941 1764 1.4000177
NOTICE main: 1 57118944 2016 1.6000290
NOTICE main: 1 57118947 2268 1.8000402
NOTICE main: 1 57118950 2520 2.0000515
NOTICE main: 1 57118953 2772 2.2000628
NOTICE main: 1 57118956 3024 2.4000740
NOTICE main: 1 57118959 3276 2.6000853
NOTICE main: 1 57118962 3528 2.8000965
NOTICE main: 1 57118965 3780 3.0001078
NOTICE main: 1 57118968 4032 3.2001190
NOTICE main: 1 57118971 4284 3.4001303
NOTICE main: 1 57118974 4536 3.6001415
NOTICE main: 1 57118977 4788 3.8001528
NOTICE condsk: 1 output at 8 7 23 0
NOTICE main: 1 57118980
5040 4.0001640