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Total suspended particles

Posted: Fri May 17, 2024 2:45 am America/New_York
I have computed PM2.5 and PM10 as suggested by FAQs 4 and 5 here: https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/FAQ/.
How can I compute total suspended particles (TSP)?

Re: Total suspended particles

Posted: Fri May 17, 2024 5:04 pm America/New_York
Hello,

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Re: Total suspended particles

Posted: Thu May 30, 2024 11:58 am America/New_York
TSP surface concentration is sum of all five aerosol species in MERRA-2, i.e.,
DUSMASS + OCSMASS+ BCSMASS + SSSMASS + SO4SMASS* (132.14/96.06)

Please also refer to FAQ3 in https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/FAQ/
for the bin size defined in the MERRA-2.

Thanks.

Re: Total suspended particles

Posted: Mon Jun 03, 2024 10:05 pm America/New_York
Hello,

Thank you for the clarification.

I was wondering whether it is possible to compute TSP starting from the inst3_3d_aer_Nv collection. Consistent with the PM10 computation, I would propose the following formula:

PM10 = (1.375*SO4 + BCphobic + BCphilic + OCphobic + OCphilic + DU001 + DU002 + DU003 + DU004 + DU005+ SS001 + SS002 + SS003 + SS004 + SS05) * AIRDENS

Is this formula correct? Additionally, would it be meaningful to compare time-averaged TSP data (calculated the formula you suggested) with instantaneous values obtained using the formula above? Are these quantities comparable?

Thank you.

Re: Total suspended particles

Posted: Fri Jun 28, 2024 11:22 am America/New_York
The equation to calculate PM10 is listed in the answer to FAQ #5 on the MERRA-2 FAQ page at https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/FAQ/#.

PM10 = (1.375*SO4 + BCphobic + BCphilic + OCphobic + OCphilic + DU001 + DU002 + DU003 + 0.74 * DU004 + SS001 + SS002 + SS003 + SS004) * AIRDENS

Time-averaged and instantaneous PM10 are likely to co-vary but could contain differences. Note however that the necessary fields needed to compute PM10 are only available in the instantaneous file collection.