Dear all,
I am running CMAQv5.5 with the Process Analysis ¶ module enabled. I am analyzing the output for a single grid cell, and I find that the following cloud‑related process variables (CLDS_ASO4I, CLDS_ASO4J, CLDS_O3, CLDS_HNO3) are exactly zero for every output time step over a period of more than 700 hours.
I would expect these terms to show at least some temporal variability (positive or negative) because cloud processes – including aqueous‑phase chemistry, scavenging, and mixing – are typically active.The sulfur tracking module (STM) indicates that I have enabled liquid-phase reactions in cloud water. Even if the net effect were occasionally zero, it seems highly improbable that they remain strictly zero over such a long simulation period. I have no idea where the problem lies.
Thank you in advance for your time and expertise.