1. CAVIAR Meeting September 2010

2. ASSESSMENT OF H 2 O LINE INTENSITIES

3. Assessment of H 2 O Line Intensities 3

4. Accepted: JMS May 2010 “….compared to HITRAN2008 …. our values are higher by about 15% for intensities…” 4

5. HITRAN08 / Oudot

6. Oudot Example

7. Average “a” Parameter HITRAN08OudotUCL 3000-8000Err8000-9200Err10000-14000Err8000-9200Err8000-9200Err 0.990.031.170.050.980.061.020.051.060.04

8. CONTINUUM DETECTION

9. H 2 O Continuum Detection Fit spectral lines to simulation (with no continuum) a τ w + b τ g + τ aero + c a, b, c can vary freely τ aero is obtained from handheld aerosol instrument c is baseline shift, or continuum absorption 9

10. H 2 O Continuum Detection 10

11. H 2 O Continuum Detection 11

12. H 2 O Continuum Detection 12

13. H 2 O Continuum Detection 13

14. H 2 O Continuum Detection (25 cm -1 )

15. H 2 O Continuum Detection (1 cm -1 )

16. Conclusions H 2 O line intensities consistency analysis – 8000 - 9200 cm -1 spectral region is too weak in HITRAN08 by about 20% – New linelist by Oudot gives underestimation about 3% Technique for continuum retrieval is currently being developed but initial results are promising – Revised calibration now available – Look for consistently across a number of days – Sensitivity tests to error in profile (e.g 1% ppmv how does retrieved continuum change) – Refine aerosol contribution Compare retrieved continuum to new CAVIAR laboratory measurements 16