@idefix37 thank you! Your answers were helpful! I've googled more and found that this is not a trivial task to get ground concentrations from the satellite integral data. There are bunch of complex models and ways to do so. I wonder why the other pollutants are presented in micrograms per m3 and only the SO2 data is in 'unpractical' units. Wish you good luck!
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RE: Probably wrong units of SO2 concentration
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RE: Probably wrong units of SO2 concentration
@idefix37 oh, I'm sorry, my bad... Is it possible to convert this to micrograms per m^3 somehow? I tried to google this with no success. I tried to use the formula (Ideal gas law):
pV=(m/M) RT like this:
For example in Moscow was 10 milligrams per m2 today
Temperature = 23 °C = 296 K
V = 1 m3
So p = 10e-6 * g = 10e-6 * 9,81 = 9,81e-5 Pa (partial pressure of SO2)
Molar mass M of SO2 is 64e-3 kg per molem = pM/(RT) = 9,81e-5 * 64e-3 / (8,31 * 296) = 2,6 micrograms per m^3
But I'm not quite sure if this correct convertion. Russian state threshold limit value of SO2 is 50 micrograms per m3 - it is about 195 milligrams per m2 (by the formula above) in Shanghai is now more than 230 mg/m2
Is this convertion correct? (seems legit, but...)Also I've found another 'bug' : when I flip my phone the value can change up to 10 times in the same area
Latest posts made by AirPollutant
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RE: Probably wrong units of SO2 concentration
@idefix37 thank you! Your answers were helpful! I've googled more and found that this is not a trivial task to get ground concentrations from the satellite integral data. There are bunch of complex models and ways to do so. I wonder why the other pollutants are presented in micrograms per m3 and only the SO2 data is in 'unpractical' units. Wish you good luck!
-
RE: Probably wrong units of SO2 concentration
@idefix37 oh, I'm sorry, my bad... Is it possible to convert this to micrograms per m^3 somehow? I tried to google this with no success. I tried to use the formula (Ideal gas law):
pV=(m/M) RT like this:
For example in Moscow was 10 milligrams per m2 today
Temperature = 23 °C = 296 K
V = 1 m3
So p = 10e-6 * g = 10e-6 * 9,81 = 9,81e-5 Pa (partial pressure of SO2)
Molar mass M of SO2 is 64e-3 kg per molem = pM/(RT) = 9,81e-5 * 64e-3 / (8,31 * 296) = 2,6 micrograms per m^3
But I'm not quite sure if this correct convertion. Russian state threshold limit value of SO2 is 50 micrograms per m3 - it is about 195 milligrams per m2 (by the formula above) in Shanghai is now more than 230 mg/m2
Is this convertion correct? (seems legit, but...)Also I've found another 'bug' : when I flip my phone the value can change up to 10 times in the same area
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Probably wrong units of SO2 concentration
Hi! Here's a screenshot from Android Russian version of Windy. I guess it should be micrograms not milligrams. Screenshot_20200823-021949_Windy.jpg