Grid concentrations not what I expect
Posted: May 26th, 2025, 9:54 am
I'm simulating four fires emitting 15000 g/hr PM2.5 per hour, for 24 hours, starting 2024 30 00, and the particle plot (PARTPLOT) shows what I would expect. Particles being emitted for 24 hours, dispersing and then ceasing to emit after 24 hours. The grid concentrations however, seem to show emissions for a couple hours at height of 1m, then almost nothing (as shown by the grid concentrations around the emission points after 4-5 hours at a height of 1m), then a slight increase in concentration about 18 hours after emission started. The graph (Picture 3) enclosed are the average concentrations for 5 different heights across the whole area where grid concentrations have been detected at 5 different levels. The weather is nothing special. The PBLH and the surface temp (TMPS, see graph) however vary significantly during the day, the wind is a little breeze. I can't explain the lack of concentrations around these emission points while the particles tell a different story. Can someone shed some light on this for me please?