“EMISNOX” is the name of the parameter appearing above this one that you want the second order for. In this file you could have also specified the “cross” sensitivity:
2X
HIGH
EMISNOX
EMISSO2
Identically:
2X
HIGH
EMISSO2
EMISNOX
Dear professor, thanks for your answer. I am a student doing the research about the sensitivity of pm2.5 in Shanghai by CMAQ-DDM. I had sent an email to this address “napelenok.sergey@epa.gov” ,I want to ask you some questions.
First, as you said, “2ENOX” means second-order sensitivity, theoretically, how to describe the third-order sensitivity ? And does the “cross” sensitivity mean the sensitivity to a combination of two emission situations “EMISSO2” and “EMISNOX”?
Second, the units of the variables in DDM result file “ASENS” are “ppmv” and “micrograms/m**3” , which are same as the units in “ACONC” file, so I’m a little confused about the meaning of the variables in “ASENS” file. In my opinion, I think the value of the variable, for example “NO2_EMISNOX”, is the slope of the green line as shown in the picture below, is that right?
Looking forward to your reply, thanks!