Conference and Seminar Proceedings

Technical Seminar on Vertical References Frame in Practice

27-28 July 2015 in Singapore


Monday 27th July 2015

08:30 – 09:00

Welcome and Opening Remarks -

  • Mr. Nic Donnelly, New Zealand
  • Prof. Chris Rizos, Australia
  • Mr. Victor Khoo, Singapore
  • Ms Sharafat Gadimova, Austria
09:00 – 10:30 Session 1: Introduction and Definitions

Prof. Chris Rizos, Australia

Need for, benefits and applications of a height system, Height systems: Geometric height systems, Physical height systems, Physical reference surfaces (geoid, quasi-geoid), Geopotential numbers, Physical heights (dynamic, orthometric, normal, MSL), Measuring potential differences (levelling+gravity), Datum definition concepts.
10:30 – 11:00 Morning Tea
11:00 – 12:30

Session 2: Time Dependence and Transformations

Prof. Chris Rizos, Australia

Time-dependent heights: Earth tides, Glacial Isostatic Adjustment (GIA), Subsidence, Episodic vertical displacements (e.g. earthquakes, volcanos, landslides); Transformations.

12:30 – 13:30 Lunch
13:30 – 15:30

Session 3: Case Studies I

Mr Basara Miyahara, Japan
Case study of Japan

Current vertical datum of Japan, Maintenance of datum utilizing COR (monitoring of displacements by CORS, revision of heights in case of earthquakes), Orthometric height determination with a hybrid geoid model.

Mr. Simon CW Kwok, Hong Kong
Modernization of Height System in Hong Kong

Hong Kong vertical reference system, Hong Kong Principal Datum (HKPD), Modernizing the vertical height system by (1) a comprehensive re-levelling of the bench mark network, (2) re-adjustment of the levelling measurement with reference to the HKPD, (3) densify a network of points covering the whole territory of Hong Kong with levelling, GNSS and gravity observations, and (4) creation of a Geoid Model for GNSS heighting in Hong Kong.

15:30 – 16:00

 Afternoon Tea

16:00 – 17:30

Session 4: Airborne Gravity for an improved vertical datum and ICG

Mr Nic Donnelly, New Zealand
Airborne Gravity for an improved vertical datum

Contribution of airborne gravity to the geoid/quasigeoid, planning an airborne gravity survey, flying airborne gravity, data processing, calibration lines, assessment of results, using New Zealand as an example

Ms Sharafat Gadimova, Austria
Presentation of International Committee on GNSS (ICG) at UN

The presentation will highlight the latest developments in the ICG and the future role of ICG in a multi-constellation GNSS. The outline of the ICG's Programme on GNSS applications, focusing on capacity-building in the use of GNSS-related technologies in various rapidly growing fields of science and industry will be provided.

19:00 – 22:00

 Seminar Dinner

Tuesday 28th July 2015

14:00 – 15:30

Session 5: GNSS Heighting and Episodic Vertical Displacements

Mr. Richard Loo and Mr. Victor Khoo, Singapore
GNSS Heighting and Application to Singapore

The presentation will introduce the height datum used in Singapore, describe the computation of geoid model, usage of GNSS in heighting and the importance of the height datum.

Mr Nic Donnelly, New Zealand
Incorporation of episodic vertical displacements into vertical reference frames

Types of vertical displacement, impact on vertical reference frames, data collection, managing the relationship between geometric and vertical reference frames, user requirements for vertical deformation modelling, incorporating a deformation model into a vertical reference frame

15:30 – 16:00

 Afternoon Tea

16:00 – 17:30

Case Studies II

Mr Graeme Blick, New Zealand
Case Study New Zealand

New Zealand’s levelling datums, New Zealand Quasigeoid 2009, New Zealand Vertical Datum 2009, relationships between levelling and quasigeiod-based reference frame, the role of the vertical reference frame in earthquake recovery, user requirements for the vertical reference frame, proposed new vertical reference frame for New Zealand

Dr. John Dawson, Australia
Case Study Australia

The Australian Height Datum (AHD). Maintenance of AHD using GNSS, a new national geodetic adjustment and refinement of AUSGeoid - Australia’s combined gravimetric–geometric quasi-geoid model. The use of Interferometric Synthetic Aperture Radar (InSAR) to develop a national deformation model to support height system maintenance.


Closing Remarks – FIG Commission 5, IAG