Calculate MEGANv2.1 ISOP emissions

[yuqiang_zhang@duke_edu]

Hi,This is my first time to run CESM v1.2.2,  and I am going to calculate the ISOP emissions from MEGAN v2.1 in CESM 1.2.2. From the manual, it says the monthly output "MEG_compound" should be multiplied by the "landfrac" value to get the true emissions. I was wondering where should I find this variable? I have checked the CAM h0, and GEOS5 meteorology file, but didn't find it. Thanks for your time! 

 

[tilmes]

Hi Yuqiang,if you are using the values MEG_* from the atmospheric output, you do not need to multiply the values by the land fraction. The manual is a little confusing on that and we will modify it.Simone 

 

[yuqiang_zhang@duke_edu]

Hi Simone,Got it.  I will follow your suggestion.BTW, the sentences I saw are from here: "How to use MEGAN in CESM1.1.1,  6 March 2013". I think that's the latest manual I could find to use MEGAN v2.1 in CESM.  

 

[yuqiang_zhang@duke_edu]

Hi Simone,I am testing the CamCHEM performance running the simulation in 2006 with MEGANV2.1 on in CESM1.2.2. I am running the similar condition under the manual for MEGAN: CAM/CLM: CAM4METEOROLOGY: GEOS5BGC,LAI: offYear: 2006 However my MEGAN emissions are a little lower compared with the reported values from the manual:Manual:                   Isoprene (474.8 tg/yr),  Methanol (84.5 tg/yr),  Acetone (60.0 tg/yr)Mine CAM h0 output: Isoprene (418.2 tg/yr),  Methanol (86.6 tg/yr),  Acetone (39.2 tg/yr)Mine CLM2 h0 output: Isoprene (539.8 tg/yr),  Methanol (110.124 tg/yr),  Acetone (52.1 tg/yr) As you can see, my Isoprene and Acetone emissions from MEGAN are lower compared with the manual. Besides, I also noticed that there are large discrepancies for the results between CAM h0 output and CLM2 h0 output. Do you know why? Did I miss something? Thanks!