1. Meteorological update and modeling plans within GEOMON Peter van Velthoven, KNMI Meteo status: almost complete up to April 2008

2. Overview From my presentation of last year: WAS-trajectories Supersaturation in ECMWF New: 2-day forward trajectories static and dynamical tropopause height planned: TTL base height, eq.PV latitude Geomon Act. 5.1 demonstration plans: Greenhouse gases pilot Reactive gases pilot

3. WAS-trajectories 8 day backward trajectories every 6 seconds (0.1 min) WAS-samples are taken within a minute so the trajectories stick very close together, therefore: 15 additional trajectories are calculated in a cube centred around the sample to indicate uncertainty. p was 1.03 p was 0.97 p was 0.8  longitude 0.8  latitude WAS pressure

4. WAS sample 22 from flight 153 31 May 2006 WAS trajectories (each 6 secs) WAS “volume” trajectories Ordinary trajectories for 1 flight hour (5-day backward)

5. New ECMWF scheme for water vapour (super)saturation over ice From 13 september 2006 onward Tompkins, Gierens & Rädel: QJRMS, 133, 622, p.53, 2006 ECMWF newsletter 109, p. 26, 2006

6. New ECMWF scheme for water vapour (super)saturation over ice

8. Static tropopause WMO-definition: the lowest level at which the lapse rate decreases to 2 °C/km or less, provided that the average lapse rate between this level and all higher levels within 2 km does not exceed 2 °C/km. lapse rate = dT/dz

9. Potential vorticity, PV A conserved quantity for adiabatic, frictionless motions (material contours!) Not conserved when there is latent heating (precipitation, evaporation) friction (at the earth’s surface) turbulence/wave-background flow interaction at scales not resolved by the model PV= .  /   -g(f +  v/  x -  u/  y)  /  p 1 PVU =10 -6 K m 2 kg -1 s -1

10. Tropopause “calculation” on ECMWF model levels Flight 220 More noisy Not valid in tropics Dynamic TP (3.5 PVU) Static TP (WMO definition) To be included in merged files …?

11. New: 2-day forward trajectories calculated for each flight Questions? Produced at request of IFT Data+plots are on website

12. Questions?

13. The end Questions? and CARIBIC.

14. GEOMON Act 5.1: Greenhouse gases pilot Objectives: Demonstrate use of GEOMON GG observations (Act.1) Use GEOMON CARIBIC obs. (CH 4, CO) to evaluate model simulated large scale gradients in the upper troposphere/lower stratosphere Use GEOMON surface obs. (CH 4, CO) to evaluate surface large scale/interhemispheric gradient and seasonal cycle IPSL: Compare modelled and observed climatologies of CO 2

15. GEOMON Act. 5.1 Greenhouse gases pilot set-up 3 global models driven by ECMWF meteo: TM4 (KNMI), LMDZ-INCA (CEA/LSCE), CTM2 (Un. Oslo) Free running methane (no surface BC for CH 4 but emissions) Output: modelled mixing ratios of CH 4 and CO at the surface stations (at hourly resolution) and along the CARIBIC flight paths (at 3 minute resolution) Time planning : June 2009: Report on preliminary model evaluation (2005) Dec 2010: Report on final model evaluation (1997- Apr 2002, Dec 2004 onward)

16. GEOMON Act 5.1: Reactive gases pilot Objectives: Demonstrate use of GEOMON reactive gas observations (Act.2) Use GEOMON CARIBIC and satellite observations to evaluate the ability of the model(s) to simulate oxygenated hydrocarbons incl. their seasonal cycle – important for upper tropospheric HO x production Would use CARIBIC obs. of O 3, HCHO, acetone, (methanol), NO y..

17. WP5.1 Evaluation of forward models with GEOMON observations of greenhouse and reactive gases

18. The end Questions?