# Presentation: 474528

## The Odin/SMR  Experiment and 

**The Odin/SMR  Experiment and **
**SMR versus MLS CO**
- B. Barret, P. Ricaud, E. Leflochmoën
- Laboratoire d’Aérologie / Observatoire Midi-Pyrénées, Toulouse, France

## The Odin satellite

- Mini-satellite
- Swedish-led project, France, Canada and Finland
- 50 % aeronomy, 50% astronomy
- 250 kg
- Sun synchronous orbit 18:00 hour ascending node
- 620 km altitude
- Latitude coverage: 83°S-83°N
- 2 instruments :
- Microwave (SMR): 119 and 480-580 GHz
- UV/VIS and IR (OSIRIS): 200-700 nm and 1.27 m
- Target Molecules:
- Ozone, chlorine monoxide, water vapour, daytime NO2, N2O, HNO3, Isotopes of H2O and O3, CO ...
- Launch in Feb. 2001 (START-1)

## SMR instrument setup

**541-558 GHz**

**486-504 GHz**

**563-581 GHz**

**547-564 GHz**

**118-119 GHz**

**SMR instrument setup**

## Slide 4

## SMR molecules

| Frequency (GHz) | Molecule | Altitude (km) | Molecule | Altitude (km) |
| --- | --- | --- | --- | --- |
| 501.18-501.58 | O3 | 18-45 | ClO | 15-55 |
| 501.98-502.38 | N2O | 14-55 |  |  |
| 544.20-545.00 | HNO3 | 20-50 | O3 | 14-70 |
| 488.95-489.35 | H218O | 22-65 | O3 | 18-60 |
| 488.35-488.75 | H216O | 22-72 |  |  |
| 556.60-557.40 | H216O | 33-100 | O3 | 35-60 |
| 576.06-576.86 | O3 | 18-80 | CO | 18-90 |
| 489.95-490.75 | HDO | 17-65 | 18O3 | 20-45 |

**SMR molecules**

## Antarctic Vortex Split 2002

- Odin

**19-20/09/02**

**25-26/09/02**

**1-2/10/02**

**4-5/10/02**

**ClO**

**O3**

**N2O**

**ClO**

**O3**

**N2O**

- REPROBUS

**Antarctic Vortex Split 2002**

- Ricaud et al. JGR, 2005

## Odin

- O3

- ClO

- N2O

- NO2

- Reprobus

- HNO3

**Antarctic Vortex Split 2002**

- Ricaud et al. JGR, 2005

- 4-5 October 2002

## CO in the stratosphere and mesosphere

- Dupuy et al. GRL, 2004

- Jin et al. GRL, 2005

- Tropics SH (01-04/2004)

- High lat. SH (05-2004)

- High lat. NH (03/2004)

- ACE/SMR CO intercomparison

## SMR radiances @ 576.4 GHz 

**SMR radiances @ 576.4 GHz**

- Mid-latitude SH
- 32.7°S / 48.2°E

- High latitude SH
- 80.9°S / 105.2°E

- 2004-25-08

**CO**
- 576.268 GHz

**O3**
- 576.515 GHz

- ~ 20 km

- ~ 31 km

- ~ 42 km

- ~ 70 km

## CO @ 576.3 GHz 

- High latitude SH
- 80.9°S / 105.2°E

- 2004-25-08

- Mid-latitude SH
- 32.7°S / 48.2°E

**CO @ 576.3 GHz**

- Res. ~ 2 km

- Res. ~ 6 km

- 18-90 km

## SMR/MLS CO : selection of data

- SMR (ref. code version 225)
- Measurement response > 0.75
- Good convergence
- MLS (V1.5 L2 data quality and description document)
- Status = 0 + clouds (p < 100 hPa)
- Precision > 0
- Quality > 0.05
- Coincidence criteria
- Distance < 500 km
-  t < 6 hours

##  SMR/MLS CO : single profiles

*** *****SMR/MLS CO : single profiles**

- SH/High Lat.

- SH/Mid. Lat.

- NH/Mid. Lat.

- NH/High Lat.

- 25/26 August 2004

##  SMR/MLS CO : zonal means

##  SMR/MLS CO : correlations

## Mean profiles
Good agreement from 14.6 to 0.1 hPa
MLS > SMR above 0.1 hPa  bias up to 100%
MLS very noisy
MLS has strong permanent negative oscillations (tropics and high norhern latitudes)

Correlations
High correlations in the upper stratosphere (around 6.8 hPa)
Slope MLS/SMR ~ 1 in this region

- Good agreement from 14.6 to 0.1 hPa
- MLS > SMR above 0.1 hPa  bias up to 100%
- MLS very noisy
- MLS has strong permanent negative oscillations (tropics and high norhern latitudes)
- Correlations
- High correlations in the upper stratosphere (around 6.8 hPa)
- Slope MLS/SMR ~ 1 in this region

**SMR/MLS CO : summary**