Troposphere Working Group Progress on recommendations made at the 2016 IGS workshop in Sydney, Australia Presented to the IGS Governing Board and Associate Members on 11 December 2016

Distribute the final tropo SINEX format once it is finalized (waiting on finalization) Look into AC tropo comparison report as next step to the tropo comparison database implementation. Sharyl Byram Troposphere Splinter Session Summary Recommendations Key highlights of the session included – Tropo SINEX format finalization was discussed in the context of ACs submitting their tropo results to be included in the the comparison database. There was also interest in the ACs recieving a regular comparison email of the AC results to the the final tropo estimates as a method for feedback to the ACs in a similar vein to the feedback received via ACC combination emails and other other emails sent out by other working groups. The question of who downloads/uses the tropo file sent in by the individual ACs was raised since these results are not used in a combination product.

Progress since Sydney: TWG Webpage Preview: Subdomain: twg.igs.org Similar look/navigation as MGEX Links to Tropo Comparison Tool and other projects

Progress since Sydney: SINEX_TRO & Comparisons Finalize SINEX_TRO Format Format Finalized: SINEX_TRO v2.00 (R. Pacione and J. Dousa lead) Supports: Different Sources/Long Station Names from RINEX 3/Slant Delays/Long-term Time-series Station Parameters Start up AC tropo comparisons again Sent survey out to ACs and TWG members ACs responded with positive interest! Willingness to contribute ZPD estimates Offers of help with automating

Future Work Finish TWG Website and Tropo Comparison Tool Next Steps: Finalize Design/Layout, Test, and Make Public Finalize SINEX_TRO Format Next Step: Getting IGS to formally adopt Start up AC tropo comparisons again Next Steps: [To Be Discussed at TWG meeting] Start with Repro2 Incorporated into Tropo Comparison Database Tool Automate comparisons of Final Estimates? Or Ultra Estimates? Discuss with Jan on possibility of using Tropo Comparison Database /How to automate and send out reports?

Contact: Sharyl Byram sharyl.byram@usno.navy.mil Thank You Contact: Sharyl Byram sharyl.byram@usno.navy.mil