Session 1: Reference Systems, Frames, and Height Systems in Physical Geodesy

Conveners:

Riccardo Barzaghi, Ezequiel Antokoletz, Onkar Dikshit

This session addresses theoretical and practical developments in terrestrial and space-based reference systems and their role in gravity field modelling and vertical datum realization. Topics include the realization and maintenance of global and regional reference frames, the integration of geometric and physical heights, vertical datum modernization, geopotential number determination, time-dependent reference frames, collocation strategies, and links to the GGOS infrastructure.

Contributions addressing the unification of regional height systems and their stability under mass redistribution, as well as contributions on the International Height Reference System/Frame (IHRS/IHRF) and the International Terrestrial Gravity Reference System/Frame (ITGRS/ITGRF), are particularly encouraged. Contributions on emerging approaches, such as relativistic geodesy and optical atomic clock-based methods, are also welcome.

Session 2: Innovative Technologies in Terrestrial, Airborne, and Satellite Geodesy: Instrumentation and Analysis

Conveners:

Jakob Flury, Xiaoli Deng, Rashmi Sharma, CP Dubey

This session will explore recent advancements in both absolute and relative gravimetry, covering classical methodologies as well as cutting-edge quantum technologies. Key topics will include the development and calibration of gravimetric instruments, the use of mobile and UAV platforms for data collection, and the complexities of gravity gradiometry.

The session will also discuss optical clock-based measurements for determining geopotential, with a focus on survey design and data standardization. Additionally, this session will address significant advancements in satellite altimetry, including altimeter calibration and retracking techniques, marine gravity recovery initiatives, and analyses of sea surface height and mean dynamic topography.

SAR interferometry, especially NISAR, SWOT (Surface Water and Ocean Topography) KaRIn measurements and their applications, the role of AI/ML in enhancing studies of gravity, geoid, and mass change, along with high-resolution geoid modelling, are also welcome.

Furthermore, the session will cover data-driven inversion methods for analyzing density structures and the downscaling of satellite gravimetry data, integrated with GNSS and InSAR for various applications.

Session 3: Satellite Gravity Missions and Global Gravity Field Modelling

Conveners:

Srinivas Bettadpur, George Vergos, Balaji Devaraju

This session focuses on current and future satellite gravimetry missions and their contribution to static and time-variable global gravity field models. Topics include GRACE/GRACE-FO, GOCE, NGGM, MAGIC, and successor mission concepts; satellite-to-satellite tracking; gradiometry; constellation design, including emerging sensing technologies; global model combination strategies; data processing and inversion; uncertainty assessment; and efficient representation of high-degree gravity models.

Studies linking mission architecture with scientific and societal applications are welcome.

Session 4: Geodesy for Climate, Natural Hazards and Earth System Processes – Regional and Global Perspectives

Conveners:

V.M. Tiwari, Bramha Vishwakarma, Athina Peidou

This session invites contributions focused on climate applications, hazard assessments, and regional geodynamics. Key areas of interest include water storage dynamics, glacier mass-balance assessments, and the monitoring of hydrological extremes such as floods and droughts.

Additionally, the session will explore earthquake cycle analysis, post-seismic deformation mechanics, mantle dynamics, sedimentary basin evolution, and comprehensive environmental monitoring.

Interdisciplinary studies that combine gravity measurements with GNSS data, seismic networks, InSAR techniques, SARAL/AltiKa altimetric data, oceanographic observations, and Earth system modelling are particularly encouraged.

Contributions applying geodetic products to contexts such as monitoring the structural integrity of dams, river-linking projects, urban tunnelling, and assessing risks related to gravity-driven landslides and land subsidence are also welcome.

Session 5: Regional and Local Geodetic Observations and their Geophysical Interpretation with Special Emphasis on the Indian Tectonic Plate

Conveners:

VK Gahalaut, Hussein Abd-Elmotaal, A. Vasanthi

This session aims to advance the understanding of lithospheric structure and geodynamic processes through geodetic, gravity field, and geoid modelling approaches. It invites contributions that investigate lateral and vertical density variations associated with Moho geometry, lithospheric thickness, isostatic compensation, and long-wavelength deformation.

The session particularly encourages studies focused on the geodynamic framework of the Indian Shield, Himalayan foreland basin, Indo-Burma arc system, major sedimentary basins, and adjoining oceanic regions.

The session also seeks to highlight methodological advancements, including downward continuation of gravity data, high-resolution DEM-based corrections for topographic effects, integration of multi-platform datasets (terrestrial, airborne, and marine), and the development of advanced inversion frameworks supported by high-performance computing.

A key objective of the session is to emphasize the role of geodesy in geodynamics, encouraging the use of geodetic observations to constrain deformation, validate models, and improve interpretations of subsurface structure.

Session 6: Challenges and Solutions in Modernization of Reference Datums

Conveners:

Laura Sanchez, S. Shrivastava, Ropesh Goyal

This session invites papers on the integration of legacy and updated geodetic data in the definition and realization of national vertical datums, including land–sea unification, high-resolution sea surface topography and chart datums, vertical datum realization for islands and their connection to the mainland, and interoperability between national, regional, and international reference frames and their scientific and societal importance.

Contributions on methodological and computational strategies for achieving precise, high-resolution geoids in regions with sparse or limited data coverage, ensuring datum consistency, and transitioning from existing systems are highly encouraged.

As the fundamental spatial framework underpinning critical governmental actions, geodesy holds substantial scientific, economic, and societal significance.

This session also highlights the strategic use of gravity and geoid data to support national and regional priorities, as well as studies aligned with national geospatial policies and capacity-building initiatives.