4-azimuth MAX-DOAS measurements in Mainz Characterisation of the information content using 3D RTM

MAXDOAS horizontal (averaging) effects

MPI for Chemistry (MPIC), Mainz, Germany

T. Wagner, J. Remmers, S. Beirle

Master Thesis, Julia Remmers

Comparison of the Telescopes (5°)NO2 DSCDs

Gradient plots (1)

• Measurement for the horizontal variability• Possibility to detect sources

N

S

W E

Gradient plots (2) NO2 DSCDs

Gradient plots (3)

3D, spherical Monte Carlo RTM

MCARTIM, Tim Deutschmann

- 1D, 2D, 3D Box AMF

Visualisation of a Monte-Carlo radiative transfer simulation (yellow: surface reflection, red: Rayleigh scattering, green: particle scattering)

Box AMF 0-1km, 500nm, no aerosols

10 km

5 km

0 km-200 km 0 km 200 km

MAX-DOASelevation: 1°

horizontal grid: 8 km x 8km vertical grid: 100m

SZA: 70°

Box AMF 0-1km, 360nm, no aerosols

10 km

5 km

0 km-200 km 0 km 200 km

MAX-DOASelevation: 1°

horizontal grid: 8 km x 8km vertical grid: 100m

SZA: 70°

Box AMF 0-1km, 360nm, aerosols 1-1km, OD 0.5

10 km

5 km

0 km-200 km 0 km 200 km

MAX-DOASelevation: 1°

horizontal grid: 8 km x 8km vertical grid: 100m

SZA: 70°

Box AMF 0-1km, 360nm, no aerosols

10 km

5 km

0 km-200 km 0 km 200 km

MAX-DOASelevation: 1°

horizontal grid: 8 km x 8km vertical grid: 100m

SZA: 70°

Box AMF 0-1km, 360nm, no aerosols

10 km

5 km

0 km-200 km 0 km 200 km

MAX-DOASelevation: 2°

horizontal grid: 8 km x 8km vertical grid: 100m

SZA: 70°

Box AMF 0-1km, 360nm, no aerosols

10 km

5 km

0 km-200 km 0 km 200 km

MAX-DOASelevation: 5°

horizontal grid: 8 km x 8km vertical grid: 100m

SZA: 70°

Box AMF 0-1km, 360nm, no aerosols

10 km

5 km

0 km-200 km 0 km 200 km

MAX-DOASelevation: 10°

horizontal grid: 8 km x 8km vertical grid: 100m

SZA: 70°

Box AMF 0-1km, 360nm, no aerosols

10 km

5 km

0 km-200 km 0 km 200 km

MAX-DOASelevation: 30°

horizontal grid: 8 km x 8km vertical grid: 100m

SZA: 70°

Box AMF 0-1km, 360nm, no aerosols

50 km

0 km

-50 km-50 km 0 km 50 km

horizontal grid: 2km x 2km

SCIA: 30 km x 60 km

MAX-DOAS

elevation: 1°

Box AMF 0-1km, 360nm, no aerosols

50 km

0 km

-50 km-50 km 0 km 50 km

horizontal grid: 2km x 2km

SCIA: 30 km x 60 km

MAX-DOAS

elevation: 1°

Box AMF 0-1km, 360nm, no aerosols

50 km

0 km

-50 km-50 km 0 km 50 km

horizontal grid: 2km x 2km

SCIA: 30 km x 60 km

MAX-DOAS

elevation: 1°

Box AMF 0-1km, 500nm, no aerosols

50 km

0 km

-50 km-50 km 0 km 50 km

horizontal grid: 2km x 2km

SCIA: 30 km x 60 km

elevation: 1°

Box AMF 0-1km, 500nm, aerosols: 0-1km, OD 0.1

50 km

0 km

-50 km-50 km 0 km 50 km

horizontal grid: 2km x 2km

SCIA: 30 km x 60 km

elevation: 1°

Box AMF 0-1km, 500nm, aerosols: 0-1km, OD 0.2

50 km

0 km

-50 km-50 km 0 km 50 km

horizontal grid: 2km x 2km

SCIA: 30 km x 60 km

elevation: 1°

Box AMF 0-1km, 500nm, aerosols: 0-1km, OD 0.3

50 km

0 km

-50 km-50 km 0 km 50 km

horizontal grid: 2km x 2km

SCIA: 30 km x 60 km

elevation: 1°

Box AMF 0-1km, 500nm, aerosols: 0-1km, OD 0.5

50 km

0 km

-50 km-50 km 0 km 50 km

horizontal grid: 2km x 2km

SCIA: 30 km x 60 km

elevation: 1°

Box AMF 0-1km, 500nm, aerosols: 0-1km, OD 1

50 km

0 km

-50 km-50 km 0 km 50 km

horizontal grid: 2km x 2km

SCIA: 30 km x 60 km

elevation: 1°

Conclusions

• Horizontal gradients can be determined from 4-azimuth MAX-DOAS observations

=> information on location of sources

• 3D-distribution of the sensitivity of MAX-DOAS depends strongly on wavelength and aerosol load

• horizontal area with box-AMF > 1 ranges typically from ~3 km to ~30 km

• spatial resolution of future satellite instruments maches that of MAX-DOAS observations (or is even finer)

6/24/09 04:48 6/24/09 09:36 6/24/09 14:24 6/24/09 19:12

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Cabauw, 24.06.2009

6/21/09 04:48 6/21/09 09:36 6/21/09 14:24 6/21/09 19:12

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