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aerosol data

Posted: Sun Feb 05, 2023 10:05 am America/New_York
by mayurichetia
when we analyze P. M 2.5 and PM 10 aerosols data from the AOD data of MODIS or sentinel 5P, is it correct to extract data from the monthly averaged AOD to PM 2.5 or PM 10 by applying the formula or do we have to extract it from the daily dataset on a daily basis?

Re: aerosol data

Posted: Tue Feb 07, 2023 11:37 am America/New_York
by GES DISC - jimacker
Hello,

Could you please point us to, or describe, which specific PM2.5 and PM10 data you used or intend to use? This will assist us in answering your question.

Monthly mean AOD data from MODIS and Sentinel-5P (TROPOMI) is usually calculated from daily mean data with caveats, such as only daytime data is included because it is the passive satellite retrieved AOD (thus only determined with visible wavelength data).

Re: aerosol data

Posted: Wed Feb 08, 2023 1:46 am America/New_York
by mayurichetia
For MODIS 10km (MYD04_L2), MODIS L3 product MYD08_D3 and for OMI 0.25°AOD data of 342.5nm spectral range i.e (OMAEOROe v003) products.

Re: aerosol data

Posted: Thu Feb 09, 2023 4:23 pm America/New_York
by GES DISC - jimacker
Hello,

Here is more information in response to your question.
"I would like to suggest extracting PM2.5 from the daily AOD, and then calculate the monthly mean PM2.5. As such, the monthly PM2.5 value is more precise. When you convert AOD to PM2.5, you might need to consider the factors such as PBLH (Planetary Boundary Layer Height) and RH (Relative Humidity), which vary with the time of day and day of the month. Thus it is more precise to convert PM2.5 on a daily basis first."

Re: aerosol data

Posted: Tue Feb 14, 2023 2:27 pm America/New_York
by mayurichetia
Can you please recommend any training programme, article, or other online resource where I can learn how to accurately and thoroughly extract data on tropospheric PM 2.5 concentrations from AOD using python, the Google Earth engine, or some other method? Additionally, I'm interested in tropospheric SO2 data extraction. These two are for the whole Indian subcontinent.

Re: aerosol data

Posted: Tue Feb 14, 2023 2:41 pm America/New_York
by GES DISC - jimacker
I will check with my colleagues. To begin, I recommend this ARSET training set of videos (from a class), particularly part 3.

https://www.youtube.com/playlist?list=PLiuUQ9asub3TPlA3RZuMJ_mHLuy6W5tGe