************************************************************************
IERS Message No. 430                                      April 08, 2021
************************************************************************


IAG 2021, Session 1.2 on global reference frame theory and methodology


Dear Colleagues,

We would like to draw your attention to Session 1.2 "Advancements and
open problems in global reference frame theory and methodology" of the
upcoming Scientific Assembly of the International Association of
Geodesy, taking place as virtual meeting between June 28 - July 2, 2021.
This is a joint session between IAG Commission 1 (Reference Frames) and
the IAG Inter-commission Committee on Theory (ICCT).

Please consider to submit an abstract to this session. See
http://www.iag2021.com/en/web/index/1646_140108 for this and other
sessions of the Commission 1 Symposium at the IAG 2021 Scientific
Assembly.

Abstract submission deadline: 30th April 2021
(http://www.iag2021.com/en/web/index/1646_802946)

We are looking forward to your contributions. With apologies for
cross-postings.

Best regards,
Christopher Kotsakis, Mathis Blossfeld, Junping Chen


Session 1.2: Advancements and open problems in global reference frame
theory and methodology

The goal of this session is to provide a forum to discuss the current
state of reference systems theory and its implementation aspects for the
realization of global terrestrial reference frames (TRFs) on the
deforming Earth. It aims also to look beyond current practices by
addressing open problems, data modeling issues and methodological
advancements that are crucial for augmenting both the long-term
stability and the short-term predictability of station positions in
global TRFs. Some themes of particular interest are: the handling of
non- secular station motions in frame estimation and the choices for
their regularized parameterization, the realization of frame origin in
relation to diverse needs of scientific users, the treatment of
geocenter motion in multi-year frame solutions, the treatment of scale
drift and its influence on the geophysical interpretability of predicted
station displacements, and the significance of network effects along
with their mitigation strategies. The session solicits contributions
covering the complete range of topics in geodetic frame theory and
estimation, including

- Conceptual definitions and adequacy of adopted conventions.
- Improved methods to realize global TRFs by individual space techniques
  and combination methods.
- Incorporation of new data analysis models and updated processing
  strategies.
- Better TRF utilization and novel reference frame representations to
  serve Earth science applications.
- Accuracy quantification of global TRF solutions.


Keywords: Global reference frames, station kinematic models,
non-secular frames, geocenter motion, non-tidal loading,
single-technique/multi-technique solutions, scale drift,
Earth science applications.


************************************************************************
IERS Messages are edited and distributed by the IERS Central Bureau.
If not stated otherwise, the IERS is only the distributor of the message
and is not responsible for its content.
To submit texts for distribution, please write to
<central_bureau@iers.org>.
To subscribe or unsubscribe, please create an IERS account or modify it:
https://www.iers.org/Login/Login/EN/login_node.html
or write to <central_bureau@iers.org>.
Archives: http://www.iers.org/Messages
************************************************************************