1. Retreat 2015 28.04.-30.04. Miesenbach Daniel Landskron - My previous and upcoming research 12015/04/28 Retreat 2015 Daniel Landskron

2. Overview Work together with Armin and Johannes Calculating tropospheric delays through ray-tracing carried out by Armin‘s ray-tracing program RADIATE Modeling of tropospheric delays o Mapping functions - site-augmented improvement of GPT2w - temporal improvement of VMF1 o Azimuthal asymmetry - new treatment of gradients Retreat 2015 Daniel Landskron 22015/04/28

3. Part 1 Part 1: Research in Mapping Functions Retreat 2015 Daniel Landskron 32015/04/28

4. Improvement of GPT2w Retreat 2015 Daniel Landskron 42015/04/28 a h vs. T plot for WETTZELL 2011 Shows a clear correlation If the user measures T => improve a h

5. Improvement of GPT2w Retreat 2015 Daniel Landskron 52015/04/28 If user measures also e => improve zwd zwd vs. e plot for WETTZELL 2011 Shows a clear correlation

6. Improvement of GPT2w Retreat 2015 Daniel Landskron 62015/04/28 Comparison of mf h for WETTZELL first half of 2011, T from NWM

7. Improvement of GPT2w Retreat 2015 Daniel Landskron 72015/04/28 Comparison of mf h for WETTZELL first half of 2011, T from NWM

8. Improvement of GPT2w Retreat 2015 Daniel Landskron 82015/04/28 Mapping Function Δshd [cm] T (NWM) Δzwd [cm] T (NWM) GPT2w 1.32.6 Additional measurement of T 0.92.5 Additional measurement of T, e 0.91.7 Comparison slant hydrostatic delays w.r.t. VMF1: e = 5°; averaged for 18 VLBI stations from 2011-2014, zwd from ECMWF => GPT2w well suited for site-augmented approach using in situ measurements of T, p and e

9. Improvement of GPT2w Retreat 2015 Daniel Landskron 92015/04/28 Geographical variation of the coefficient M2

10. Improvement of VMF1 (1) Calculation of new mapping function coefficients: For CONT11 From ray-traced delays using RADIATE => No clear improvement in BLR Retreat 2015 Daniel Landskron 102015/04/28

11. Improvement of VMF1 (2) Higher temporal resolution of NGS data Retreat 2015 Daniel Landskron 112015/04/28

12. Improvement of VMF1 (2) Retreat 2015 Daniel Landskron 122015/04/28

13. Part 2 Part 2: Research in Azimuthal Asymmetry Retreat 2015 Daniel Landskron 132015/04/28

14. Azimuthal asymmetry Standard gradient formula (Chen and Herring, 1997): Tropospheric delays vary for different azimuths because Atmosphere thicker at the equator E.g. weather fronts affect delay Effect is significant for low-elevation observations Retreat 2015 Daniel Landskron 142015/04/28

15. Azimuthal asymmetry New gradient formulas: Retreat 2015 Daniel Landskron 152015/04/28 WESTFORD Residuals of total slant delays

16. Azimuthal asymmetry Gradient formulas can be used: 1.as a priori gradients – gradients determined for every NWM epoch and provided in a text file – use of the new gradient formulas improves the resulting delays 2.for estimating gradients in VLBI analysis – in vie_lsm, together with zwd, station coordinates, source coordinates,.. – Use of the new gradient formulas does not yield improvement Retreat 2015 Daniel Landskron 162015/04/28

17. Azimuthal asymmetry Retreat 2015 Daniel Landskron 172015/04/28 A priori gradients(a)(b) none1.201.07 standard gradient formula1.101.05 extended formula (1)1.091.03 extended formula (2)1.091.04 BLR comparison for CONT11 in [cm]: (a)Only using a priori gradients (b)Additionally estimating gradients using standard gradient formula

18. Part 3 Part 3: teaching activities Retreat 2015 Daniel Landskron 182015/04/28

19. Teaching activities 124.026 “Geodetic Space Techniques - project handling and data processing“ exercise – takes place every even winter semester – group work – scheduling and Simulation in VieVS – final presentation of the results Willingness to do more teaching Retreat 2015 Daniel Landskron 192015/04/28

20. Part 4 Part 4: Outlook Retreat 2015 Daniel Landskron 202015/04/28

21. Outlook Collaboration with Gregor Find a way to map delays below 3° elevation as well Make everything operational, include in VieVS Make research for longer time periods Find a way to provide gradients on a grid Retreat 2015 Daniel Landskron 212015/04/28