The equation of SS aerosol reflectance to MS aerosol reflectance

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liugers11
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Joined: Fri Mar 01, 2013 2:08 pm America/New_York

The equation of SS aerosol reflectance to MS aerosol reflectance

by liugers11 » Sat Feb 02, 2019 11:49 pm America/New_York

Hi?
We want to convert the OLCI SS aerosol reflectance to MS aerosol reflectance using the equation in aerosol.c as follows.
lnrhoas = log(rhoas[iw]*aeroob(sensorID,iw,cf,wv))
rhoa[iw] = exp(a + b*lnrhoas + c*lnrhoas*lnrhoas);
I have a few questions.
(1)  for the OLCI images, can I set aeroob(sensorID,iw,cf,wv) =1?
(2)  If aeroob(sensorID,iw,cf,wv)=1, I use aerosol_olci_r80f00v01.hdf to test this process. When solz=27.5, senz=7.66769, phi=15, and wavelength=400 nm, the values of acost?bcost and ccost are-0.838569,0.850478, and -0.0152793. Do the values of acost, bcost, and ccost represent a,b and c in the above equation?
(3)  If it is true. When rhoas_400 =0.01, the calculation result of rhoa_400 is 0.006225. The MS aerosol reflectance is lower than SS serosol reflectance. Where am I wrong?
Thank you very much.

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OB.DAAC - SeanBailey
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The equation of SS aerosol reflectance to MS aerosol reflectance

by OB.DAAC - SeanBailey » Tue Feb 12, 2019 8:43 am America/New_York

> (1)  for the OLCI images, can I set aeroob(sensorID,iw,cf,wv) =1?


You could, or you could implement the correction from aerosol.c using the coefficients in $OCDATAROOT/olci/msl12_sensor_info.dat

> (2)  If aeroob(sensorID,iw,cf,wv)=1, I use aerosol_olci_r80f00v01.hdf to test this process. When solz=27.5, senz=7.66769, phi=15, and wavelength=400 nm, the values of acost?bcost and ccost are-0.838569,0.850478, and -0.0152793. Do the values of acost, bcost, and ccost represent a,b and c in the above equation?


Yes, acost, bcost and ccost are the coeffiicients for the MS->SS quadratic equation

> (3)  If it is true. When rhoas_400 =0.01, the calculation result of rhoa_400 is 0.006225. The MS aerosol reflectance is lower than SS serosol reflectance. Where am I wrong?


Don't know :sad:

Sean

liugers11
Posts: 14
Joined: Fri Mar 01, 2013 2:08 pm America/New_York

The equation of SS aerosol reflectance to MS aerosol reflectance

by liugers11 » Wed Feb 13, 2019 7:19 am America/New_York

Hi, Sean
     Thank you for your replying.  It really helps.

Best Wishes
Ge

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