RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE
description
Transcript of RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE
![Page 1: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/1.jpg)
RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE
RUTGER VAN DEELENJOCHEN LANDGRAF, ILSE ABEN
Photo credit: NASA
Buys Ballot
Research School
2004
![Page 2: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/2.jpg)
Satellite measurement of backscattered sunlight
Raman scattering features
Radiative transfer model
Model result
Application of the model
Summary
OUTLINE
![Page 3: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/3.jpg)
Sun
Earth’s
atmosphere
Earth’s
surface
SATELLITE MEASUREMENT OF
BACKSCATTERED SUNLIGHT
GOME SCIAMACHY
OMI
![Page 4: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/4.jpg)
Sun
Earth
GOME SOLAR & EARTH SPECTRUM
![Page 5: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/5.jpg)
GOME REFLECTIVITY SPECTRUMClear sky, the Netherlands, 1995, 0.2 nm spectral resolution
![Page 6: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/6.jpg)
GOME REFLECTIVITY SPECTRUMClear sky, the Netherlands, 1995, 0.2 nm spectral resolution
ozone
O2
O2O2
NO2H2O
veg
etat
ion
vegetation
![Page 7: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/7.jpg)
GOME REFLECTIVITY SPECTRUMClear sky, the Netherlands, 1995, 0.2 nm spectral resolution
ozone
O2
O2O2
NO2H2O
veg
etat
ion
vegetation
Raman
![Page 8: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/8.jpg)
ROTATIONAL RAMAN SCATTERING
Cabannes
96 % elastic
Raman
4 % inelastic
N2, O2
at 400 nm
![Page 9: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/9.jpg)
ROTATIONAL RAMAN SCATTERINGS
ola
r ir
rad
ian
ce
sca
tte
red
rad
ian
ce wavelength
![Page 10: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/10.jpg)
(ir)
rad
ian
ce
wavelengthsca
tte
red
rad
ian
ce wavelength
Sun
Earth
ROTATIONAL RAMAN SCATTERINGS
ola
r ir
rad
ian
ce
![Page 11: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/11.jpg)
wavelength
sca
tte
red
rad
ian
ce wavelength
ROTATIONAL RAMAN SCATTERINGS
ola
r ir
rad
ian
ce
refl
ecti
vit
y
![Page 12: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/12.jpg)
RADIATIVE TRANSFERRadiative transfer equation describing multiple scattering
extinction
coefficient
intensity
source functiondistance
along path
![Page 13: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/13.jpg)
MODEL RESULT
Total inelastic
fraction
Reflectivity
![Page 14: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/14.jpg)
Raman features can be used to get cloud top height
Less air, less filling in
Low
cloud
High cloud
MODEL APPLICATION
![Page 15: RAMAN SCATTERING IN THE EARTH’S ATMOSPHERE](https://reader035.fdocuments.net/reader035/viewer/2022062301/5681500d550346895dbdeea7/html5/thumbnails/15.jpg)
SUMMARY
Raman features are clearly visible in reflectivity spectra: can be as large as 20%
We have developed a radiative transfer model which takes Raman scattering fully into account
Raman features can be used to retrieve cloud top height