1. SIMULATED OBSERVATION OF TROPOSPHERIC OZONE AND CO WITH TES
Ming Luo, R. Beer, D.J. Jacob, J.A. Logan, C.D. Rodgers
(with thanks to Mark Schoeberl)
OBJECTIVES:
Optimize TES data collection strategy for 50% duty cycle
Assess TES global mapping capability
APPROACH: use global 3-D model fields (GEOS-CHEM model) as a synthetic atmosphere

2. TES OBSERVATIONAL CHARACTERISTICS
Sun-synchronous polar orbit, noon-3 p.m. observation
Nadir and limb (along-track) views
0.5x5 km nadir pixel size (8x5 km for 16 stacked pixels)
16-day orbit repeat cycle, 233 orbits per cycle
(14-15 orbits/day)

3. TEMPORAL VARIABILITY IN GEOS-CHEM MODEL
Time series of surface O3
at Mace Head, Ireland (1996)
Observed (Simmonds)
Model (Li)

4. SPATIAL VARIABILITY IN GEOS-CHEM MODEL: forecast vs
SPATIAL VARIABILITY IN GEOS-CHEM MODEL: forecast vs. observed CO concentrations in TRACE-P (DC-8 Hong Kong local 1, 7 March 2001)
Observed
(G.W. Sachse,
NASA/LaRC)
OBSERVED
(Sachse)
Lifting
ahead
of front
Boundary layer
outflow behind
front
Cold
front
GEOS-CHEM
forecast
(D.J. Jacob,
Harvard)
GEOS-CHEM
(Bey, Liu,
Yantosca)

5. OPTIMIZING THE TES DUTY CYCLE: autocorrelation of global GEOS-CHEM fields for ozone (results for CO are similar)
Global autocorrelation coefficient (r2) vs. time lag
CONCLUSION: Adopt a 1-day on, 1-day off duty cycle

6. SAMPLE 500 hPa OZONE FIELD VIEWED BY TES
GEOS-CHEM data
for Aug. 15, 1994
…sampled on TES orbit track
… and filtered for clouds
(55% of scenes)

7. RETRIEVAL OF GEOS-CHEM VERTICAL PROFILES WITH SIMPLIFIED LINEAR ALGORITHM
gain
Averaging
kernel
Retrieved
profile
measurement
noise
True profile
(GEOS-CHEM)
a priori
Error covariance
on a priori
Measurement
noise covariance
Jacobian from
TES forward model

8. GEOS-CHEM for different latitudinal bands Averaging kernels
RETRIEVAL ELEMENTS
100 hPa
1000 hPa
A priori profiles:
yearly means from
GEOS-CHEM for different
latitudinal bands
Averaging
kernels

9. ERRORS ON A PRIORI AND RETRIEVED PROFILES

10. TES RETRIEVAL OF GEOS-CHEM ATMOSPHERE: 500 hPa ozone on 15 Aug. 1994
Level 2
Level 3
(Gaussian
interpolator)

11. % RETRIEVAL ERROR: 500 hPa ozone on 15 Aug. 1994

12. OTHER SAMPLE RETRIEVALS
Ozone,
800 hPa
CO,
700 hPa
GEOS-CHEM
TES level 3 retrieval