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Satellite Orbits Supply Chain
EGV Level: 2 — Global · Geometric | Date: May 2026 | Version: 4.0
Reference: EGV White Paper V7.0 (GGOS, January 2026) · Guiding Principles v2.1 · 1st Joint Development Plan
Overview
The Satellite Orbits Essential Geodetic Variable (EGV) sits at Level 2 in the GGOS EGV framework — it is a processed, combined product derived from raw observation data and delivered as an input to the full suite of Level 3 EGVs. Within the Level 2 category, this supply chain specifically produces the GNSS Satellite Orbits, Clocks and Biases (GOCB) product set: three-dimensional orbital trajectories for all operational GNSS satellites and sub-nanosecond clock corrections for each satellite.
These products are Primary or Important inputs to ten of fourteen Level 3 EGVs, including Global Reference Frames (ITRF), Sea Surface, Sea Level, Ice Sheets, Terrestrial Water Storage, and Atmosphere. The complete dependency matrix is documented in EGV_Product_Mapping.md.
Critical circular dependency: ITRF is simultaneously a consumer of Satellite Orbits (GNSS data must use precise orbits before contributing to ITRF combination) and a prerequisite for Satellite Orbits production (SPOCC uses Helmert transformations anchored to the current ITRF). A sustained failure of this pipeline does not merely degrade Satellite Orbits — it progressively weakens the ITRF itself, cascading to every EGV with a Primary or Important dependency on Global Reference Frames.
Co-Produced EGVs
The same Tier 2–3 processing that generates Satellite Orbits simultaneously produces several additional EGV products as natural computational byproducts. The Tier 3 ACC/SPOCC bottleneck identified later in this document is therefore a multi-EGV resilience gap, not merely a risk to orbit products alone.
| EGV | Level | Mechanism |
|---|---|---|
| Station Positions and Variations | 2 | AC solutions include station coordinate time series (SPTS) in the same computational step |
| Integrated Water Vapour (IWV) | 3 input | Tropospheric delay parameters from orbit determination yield IWV directly |
| Global Ionosphere Maps (GIM) | 3 input | Ionospheric delay estimation during dual-frequency GNSS processing |
| Earth Orientation Parameters (EOP) | 3 input | Polar motion and LOD estimated as part of GNSS combination at Tier 3 |
Governance
| Institution | Role | Risk Level | Governance Gap |
|---|---|---|---|
| IGS Governing Board (IGB) — incoming Chair: Scott Luthcke (NASA GSFC) | Strategic direction and policy authority for the IGS | Medium | No formal multi-stakeholder representation for space agencies or the private sector as governance actors. No single body is formally designated as accountable for supply chain reliability. |
| IGS Central Bureau (NASA JPL) | Operational coordination hub; manages station metadata (CBIS) | Medium | No formal MoU governing CB hosting at JPL; best-effort institutional arrangement. |
| IGS Infrastructure Committee | Technical standards for tracking network and data flow | Medium | Standards improvement is reactive — triggered by failure rather than proactive lifecycle management. |
| GGOS / IAG | Scientific coordination and EGV framework definition | Low | IAG coordinates science through GGOS but holds no formal seat at IGS operational governance. Scientific leadership and operational accountability remain structurally disconnected. |
| IERS | Validates combined orbits against ITRF | Medium | No formal SLA monitoring loop reporting validation results back to UN-GGCE or GGOS. Tier 4 is not in the current UN-GGCE risk register. |
| UN-GGCE | Advocacy for supply chain resilience; reports to UN Statistical Commission/ECOSOC | Low | Currently holds observer status only within IGS governance. This limits the UN-GGCE's ability to enforce JDP Objective 1.1 requirements or mandate remediation when SLA thresholds are breached. |
Supply Chain
Tier 0 — Data Acquisition and First-Mile Telemetry
Data level: Basis — Geodetic Infrastructure. The global GNSS tracking network (107 Core Sites, ~400 standard contributing sites) constitutes the Geodetic Infrastructure Basis EGV. Raw observations become Level 1 EGV (Geodetic Observations) upon ingestion to agreed RINEX standards.
Raw GNSS signals are acquired continuously by physical tracking stations and transmitted via push telemetry to Operational Data Centres (ODCs). The primary ODCs are operated by GFZ (Germany), CNES REGINA (France), and NGS/NOAA (USA).
Accountable institutions for individual tracking sites include national geodetic agencies, research institutions, and universities — among them Geoscience Australia, BKG, IGN, and many others across the 107 Core Sites and approximately 400 standard contributing sites. While the site network itself is geographically distributed, responsibility for first-mile delivery is fragmented across these many operators, with coordination managed through the IGS Infrastructure Committee.
The first-mile connection between a physical observatory and its ODC is a known vulnerability. Many Reference Frame stations lack redundant upload paths. If the primary ODC connection fails, data is buffered locally, introducing latency that degrades real-time and ultra-rapid orbital products. Based on official IGS Network Data Flow topologies, all three primary ODCs are located in the northern hemisphere — a geographic concentration that is unaddressed in current operational risk registers but conflicts directly with Principle 1 (Geographic Distribution for Technical Performance). JDP Objective 1.2 requires regional hubs in under-represented regions, particularly the southern hemisphere.
The IGS Central Bureau (CB), hosted at NASA Jet Propulsion Laboratory (JPL), USA, is the operational coordinator for the entire pipeline — managing the network, maintaining the Central Bureau Information System (CBIS) for station metadata, and ensuring adherence to IGS standards. CB hosting at JPL rests on no formal MoU; it is a best-effort institutional arrangement. Administrative disruption at JPL would not stop orbit production immediately but would degrade the IGS's capacity to manage station changes, quality issues, and long-term network governance. JDP Objective 1.1 requires a formal hosting agreement. Key CB personnel are Léo Martire (Director — confirmed as permanent Director 2026-04-16; succession gap resolved) and Robert Khachikyan (Information Systems Manager), who leads the technical management of CBIS, the critical metadata registry.
The IGS Infrastructure Committee (IC) is responsible for standards and coordination of the physical tracking network (Tier 0) and the archiving data flow (Tier 1). IC personnel include Markus Bradke (GFZ, Germany — IC Chair, infrastructure strategy), Ryan Ruddick (Geoscience Australia — IC Vice-Chair, cross-tier coordination), David Maggert (EarthScope, USA — Network Coordinator, Tier 0 observatory network health), Ignacio Romero (ESA/ESOC, Germany — RINEX standards lead, data interoperability), and Patrick Michael (NASA GSFC/CDDIS, USA — IGS Data Center Coordinator and CDDIS Manager). The IC relies on best-effort contributions from these key individuals. Loss of institutional support for any of these roles — for example, a funding change at EarthScope or GFZ — would immediately degrade global capacity to coordinate the raw data pipeline. No succession plans are documented for any IC role.
Risk: Medium — The first-mile connection from observatory to ODC is a known vulnerability; all three primary ODCs are in the northern hemisphere, a geographic concentration that conflicts with Principle 1.
| Capability | Score | Relevant Dimension |
|---|---|---|
| GNSS Data Acquisition and Storage | 3.5 | Technology |
| SLR Data Acquisition and Storage | 3.25 | Technology |
| DORIS Data Acquisition and Storage | 4.0 | Technology |
| Ground-Based Asset Management | 1.75 ⚠ | Technology |
| Equipment Calibration and Maintenance | 3.3 | Technology |
Tier 1 — Global Archiving and Data Hierarchy
Data level: Level 1 EGV (Geodetic Observations) — RINEX files; geo-located time series with geophysical corrections applied, formatted to agreed IGS standards.
Tier 1 is the ingestion and long-term storage layer, structured as a two-level hierarchy. Regional Data Centres (RDCs) — including BKG (Germany), Geoscience Australia, KASI (South Korea), and SOPAC (USA) — act as geographic consolidators that gather data from multiple ODCs within a region. Above them, the three apex repositories — CDDIS (NASA GSFC, USA), IGN (France), and SIO (Scripps, USA) — form the Global Data Centres (GDCs), which mirror data via a continuous equalization protocol, maintaining synchronised archives across three institutions. Accountable personnel include Patrick Michael (NASA GSFC/CDDIS) as Data Center Coordinator and Ignacio Romero (ESA/ESOC) for RINEX interoperability standards, both reporting through the IGS Infrastructure Committee.
The three GDCs run a data equalization protocol that provides genuine resilience against a single GDC-site failure: if CDDIS becomes unavailable, Analysis Centres can pull identical data from IGN or SIO. CDDIS has a record of zero failure under the management of Patrick Michael, which has inadvertently created a high degree of stakeholder dependency. The real risk is that many stakeholders are unaware of where alternative data sources are located outside of CDDIS. There is a critical need for synchronised holdings across Global Data Centres to ensure that alternative sources are not just redundant in theory but accessible and known to operational stakeholders. During a U.S. government shutdown, while automated servers may remain active, the lack of manual support and the "single point of failure" perception can disrupt workflows.
The equalization protocol operates between GDCs. It cannot recover data that was never delivered to the GDC level in the first place. The correct characterisation of the 2018–2019 shutdown evidence is that the system proved resilient to single GDC-site outage (verified by architecture) but not resilient to ODC/RDC-level data gaps caused by upstream institutional disruption. During that shutdown (35 days), NASA GSFC staff furloughs caused some latency and CDDIS access issues for U.S.-operated sources (e.g., NOAA NGS Analysis Centre disruptions). However, because the Analysis Centre Coordinator (ACC) and other international ACs (e.g., ESA, CODE) remained operational, the global combination was successful. (Source: IGS 2018 Technical Report · IGSMAIL-7566.)
A further concentration risk exists at the political level: CDDIS and SIO are both U.S.-hosted institutions. The GDC network spans only two political jurisdictions (USA, France), which conflicts with Principle 2 (Political Resilience and Distributed Operational Control) and JDP Objective 1.2. There is a critical need for more Global Data Centres with synchronised holdings outside the current U.S./France footprint to ensure geographic and political diversity.
Risk: Medium — The GDC equalization protocol provides genuine resilience against single-site failure, but the network spans only two political jurisdictions and many stakeholders are unaware of alternative data sources.
| Capability | Score | Relevant Dimension |
|---|---|---|
| Network Operations | 2.25 ⚠ | Technology |
| Data Quality Management | 2.0 ⚠ | Process |
| Metadata Management | 2.0 ⚠ | Data |
| Data Preservation | 2.0 ⚠ | Data |
Note: The Technology dimension of Network Operations scores 1.0 — the single weakest score across the entire pipeline, reflecting the absence of automated failover, formal monitoring infrastructure, and documented recovery procedures at the GDC/RDC layer.
Tier 2 — Analysis Centres and the Software Ecosystem
Data level: Level 1 → Level 2 (intermediate) — individual AC precise orbit and clock solutions; processed from Level 1 data but not yet combined into the authoritative EGV product.
As registered with the IGS Central Bureau, approximately 12 independent Analysis Centres pull data from the Tier 1 GDC archives and process it to generate independent orbital trajectories and clock corrections. Key Analysis Centres include:
| Analysis Centre | Institution | Software | Methodology |
|---|---|---|---|
| JPL | NASA / Caltech, USA | GipsyX (Proprietary) | Kalman Filter |
| CODE | Univ. Bern / AIUB, Switzerland | Bernese | Batch Least Squares |
| ESA/ESOC | European Space Agency, Germany | NAPEOS | Batch Least Squares |
| GFZ | German Research Centre for Geosciences | EPOS.P8 | Batch Least Squares |
| Wuhan University | China | PANDA | Batch Least Squares |
| + 7 or more others | Various | Various | Various |
While algorithmic diversity across approximately 12 ACs is high, core applications like GipsyX (owned by Caltech) are proprietary and closed-source. This creates a proprietary dependency in Tier 2 — the source code is not available for independent maintenance or inspection. The application is distributed, but the architectural knowledge is not. Algorithmic diversity is encouraged and different software for different regions and purposes is appropriate; however, the closed-source status of GipsyX represents a specific supply chain vulnerability that distinguishes it from the open or published-method tools used by other ACs.
Intermediate solutions produced by individual ACs should be independently archived in accordance with FAIR Principle 4 — ensuring that the authoritative combination at Tier 3 can, in principle, be reconstructed or audited from component parts. This is not currently a documented operational requirement.
Knowledge fragility exists across AC teams. These centres are typically led by small specialist groups within academic or research institutions, with no guaranteed funding continuity and no documented succession planning. The retirement or departure of key scientific staff at any major AC could degrade that centre's contribution quality without any formal remediation pathway.
Risk: Medium — Algorithmic diversity across ~12 ACs is a strength, but GipsyX (JPL/Caltech) is proprietary and closed-source; key-person risk exists across AC teams with no documented succession planning.
| Capability | Score | Relevant Dimension |
|---|---|---|
| GNSS Data Processing and Analysis | 3.75 | Technology |
| Geodetic Software and Tools | 2.0 ⚠ | Technology |
| Knowledge Management | 1.3 ⚠ | People |
Note: The Process dimension of GNSS Data Processing and Analysis scores 3.0 — succession planning is not formalised across AC teams. JDP Objective 1.4 directly applies.
Tier 3 — EGV Combination — Critical Bottleneck
Data level: Level 2 EGV (Satellite Orbits — GNSS Satellite Orbits, Clocks and Biases/GOCB) — the official, authoritative combined product. This is the boundary at which intermediate AC solutions become the recognised EGV.
The independent orbital solutions from the 12 Analysis Centres are mathematically combined to produce the official Satellite Orbits EGV, distributed as three product types:
| Product | Latency | Use Case |
|---|---|---|
| Ultra-Rapid | ≤ 15 minutes | Real-time navigation, space weather |
| Rapid | ≤ 17 hours | Rapid response geodesy, daily EOP |
| Final | 12–18 days | ITRF combination, science reprocessing |
This combination involves two closely related but distinct roles. The Analysis Centre Coordinator (ACC) manages AC submissions, assigns statistical weights, oversees quality control, and runs the SPOCC software. The ACC role is currently operated by Salim Masoumi (Geoscience Australia) and Tom Herring (MIT) as Co-Leads for daily combination operations. It is transitioning from GA/MIT to GA/NASA GSFC (full operational capability expected late 2025), with the transition managed by Taylor Yates (NASA GSFC). The ACC environment is deployed on AWS (EC2 and S3, multiple geographic regions), providing infrastructure-level resilience. The Software for Precise Orbit and Clock Combination (SPOCC) is a Python-based tool developed by GFZ and deployed by the ACC. SPOCC is a proprietary tool; it is not an open-source community project. The ACC operates SPOCC, but GFZ retains deep architectural knowledge of the software, meaning that a significant software failure or major feature requirement would depend on GFZ expertise to resolve regardless of who is running the combination day-to-day.
Key SPOCC personnel at GFZ are Benjamin Männel (SPOCC Project Lead), Radoslaw Zajdel (orbit combination algorithms), and Ghazal Mansur (clock combination and VCE algorithms).
All decentralised redundancy from Tiers 0–2 converges through this single pipeline. The risk has three distinct components. First, there is no formal backup ACC: no designated successor exists if GA or its partner withdraws. The 2013 ad hoc response involving NRCan and ESA/ESOC demonstrated that a contingency exists in practice, but it has never been formalised, contracted, or rehearsed. Second, proprietary software knowledge is concentrated at GFZ: the ACC operates SPOCC day-to-day, but GFZ holds the deep architectural knowledge. No independent reimplementation exists. A major software failure or significant capability requirement would require GFZ involvement regardless of who is running the combination. This is a software key-person risk, not a software monopoly in the operational sense. Third, the ACC transition reintroduces political risk: moving the ACC back to NASA GSFC (a U.S. civil service centre) reintroduces vulnerability to U.S. federal appropriations lapses. Moving the ACC back to GSFC without a formalised, internationally governed "break-glass" protocol reintroduces a known single point of failure that the GA/MIT structure, hosted outside U.S. federal jurisdiction, had successfully mitigated.
The historical evidence is unambiguous. In the 2013 U.S. Government Shutdown, the ACC (then solely at NOAA/NGS) faced significant administrative disruption. While core IGS products continued through automated scripts and minimal excepted personnel (IGSMAIL-6826), the impact was visible in the governance record: the NGS/ACC was unable to submit its annual report to the technical record for that year. Previous characterisations of an "emergency transfer" to ESA/NRCan have been clarified as a conflation with the unrelated launch of the Real-Time Service. In the 2018–2019 U.S. Government Shutdown (35 days), the ACC (then GA/MIT) remained operationally available because it was hosted outside U.S. federal jurisdiction. While NASA GSFC staff furloughs caused CDDIS access issues and halted submissions from U.S.-funded Analysis Centres (e.g., NGS), the final global orbit products were not degraded. SPOCC successfully generated the orbits using the remaining international Analysis Centres (e.g., ESA, CODE). This proved the decentralised model works when the ACC itself is not compromised. (Source: IGS 2018 Technical Report · IGSMAIL-7566.)
The 2025-2026 period represents the most severe sustained disruption to US-hosted IGS infrastructure since 2018-2019 — and it coincides directly with the ACC transition to NASA GSFC. In January 2025, the Los Angeles wildfires caused a confirmed six-day disruption to data deliveries from JPL, which hosts the IGS Central Bureau (IGSMAIL-8553). From February 2025 onward, DOGE-related workforce reductions removed approximately 25% of staff at NOAA/NGS (an IGS Analysis Centre), approximately 32% of civil servants at NASA GSFC (which hosts CDDIS — the primary Global Data Centre), and approximately 25% of the total workforce at JPL across four rounds of layoffs. The US government shutdown of 1 October to 12 November 2025 (42 days) furloughed approximately 15,000 NASA civil servants, including GSFC staff sustaining CDDIS and the Space Geodesy Project, during the same period in which the ACC transition to GSFC was under active preparation. No IGS product delivery failure has been attributed to any of these events in the mail archive — consistent with the 2018-2019 pattern in which automated data flows continued even as human oversight capacity degraded — but the administrative impact will only be visible retrospectively in the IGS Technical Reports, none of which have been published for 2024 or 2025 at the time of this assessment.
A longitudinal review of IGS Technical Reports (2013 and 2018) reveals a persistent pattern of systemic administrative fragility: "No report submitted" entries appear consistently across critical tiers. At Tier 1, SIO, IGN, and KASI consistently failed to submit annual reports in both 2013 and 2018. At Tier 3, critical working groups including Clock Products, Orbit Dynamics, and the foundational Reference Frame Working Group (in 2018) failed to document their activities. This represents a major gap in global network monitoring and is a direct manifestation of low maturity in Network Operations. While the supply chain maintains technical data flow, it lacks the administrative resilience and transparent reporting required for a robust intergovernmental infrastructure — a direct gap against Principle 6 (Transparency and Performance Accountability).
One partial mitigation available to NASA GSFC is the U.S. government's "critical activity" designation: functions formally classified as critical under federal continuity-of-operations rules are exempted from appropriations-lapse shutdowns. If the ACC function at GSFC were to receive this designation, automated operations could continue through a funding lapse. However, this designation has not been confirmed for IGS or ACC functions at GSFC — and the 2013 precedent is instructive: the ACC at NOAA/NGS was not classified as a critical activity and was fully furloughed. Critically, even if the designation were granted, it would remain a unilateral U.S. government decision rather than an internationally governed continuity mechanism, and could be revoked or re-scoped without notice to the international geodetic community. It therefore mitigates but does not resolve the jurisdictional risk.
The NRCan/ESA contingency demonstrated informally in 2013 remains ungoverned. No SLA, MoU, or trigger criteria exist for activating this failover. No regular rehearsal exercises have been conducted. This arrangement directly conflicts with Principle 2 (Political Resilience and Distributed Operational Control) and JDP Objective 1.1. Formalising this contingency and resolving the ACC transition political risk are prerequisites for this tier to meet the standard required by Principle 3 (Centralised Accountability through Multilateral Governance).
Risk: Critical — All decentralised redundancy from Tiers 0–2 converges through this single pipeline. No formal backup ACC exists; SPOCC architectural knowledge is concentrated at GFZ; the ACC transition back to NASA GSFC reintroduces U.S. federal political risk that the GA/MIT structure had successfully mitigated.
| Capability | Score | Relevant Dimension |
|---|---|---|
| Geodetic Data Products | 2.8 ⚠ | Data |
| Performance Management | 2.0 ⚠ | Process |
| Risk Management | 1.0 ⚠ | Process |
| Disaster Recovery and Supply Chain Continuity | 1.7 ⚠ | Process |
| Knowledge Management | 1.3 ⚠ | People |
Tier 4 — Validation and Distribution
Data level: Level 2 EGV (Satellite Orbits — validated and distributed) — the Satellite Orbits EGV as validated by IERS and distributed through the IGS archive network and NTRIP streams.
Tier 4 represents the terminal stage of the supply chain: independent validation by the International Earth Rotation and Reference Systems Service (IERS) against the current ITRF, followed by public distribution through the IGS archive network and NTRIP streams. Accountable institutions are IERS (multi-agency, coordinated through the IERS Central Bureau at BKG, Germany) and the IGS distribution network partners.
Both validation (IERS) and distribution (IGS) exist and function operationally. However, neither function is governed by formal SLAs, performance targets, or public reporting obligations. Tier 4 does not appear in the current UN-GGCE risk register, which is a gap: if validation is delayed or distribution is degraded, downstream Level 3 EGV pipelines have no formal remediation trigger.
Principle 6 (Transparency and Performance Accountability) and JDP Objective 1.1 require formal SLA-based performance monitoring at Tier 4 with published targets for validation turnaround and distribution uptime; a defined escalation process when targets are not met; and integration of Tier 4 metrics into the GGOS/UN-GGCE performance reporting cycle.
Until this governance is established, Tier 4 represents an unmonitored tail risk — adequate under normal operating conditions but without formal accountability if it degrades.
Risk: Not Currently Governed — Validation and distribution exist operationally but are absent from the UN-GGCE risk register. Neither function is covered by SLAs, performance targets, or a formal accountability mechanism. Tier 4 has no formal home in the current risk governance framework; under Principle 6 and JDP Objective 1.1, this tier requires explicit SLA-based monitoring before it can be assessed.
| Capability | Score | Relevant Dimension |
|---|---|---|
| Geodetic Services | 2.0 ⚠ | Process |
| Data Distribution | Unscored | Data |
| Regulatory Compliance | 3.0 | Process |
| Standards Development and Promotion | 3.0 | Process |
Workflow Diagram
JDP Alignment
| Pipeline Element | Current State | Gap | JDP Objective |
|---|---|---|---|
| CB hosting at NASA JPL | No MoU; best-effort arrangement | Sole institutional host with no formal agreement or continuity plan | 1.1 — SLAs and MoUs for all critical functions |
| ACC operational agreement (GA + MIT → GA + NASA GSFC) | Informal coordination; no SLA | Two Co-Leads with no succession plan; transition back to U.S. federal jurisdiction reintroduces political risk | 1.1 — Formalised long-term operational agreements |
| NRCan/ESA contingency failover (Tier 3) | Theoretical failover path; unrehearsed | Not a governed protocol; no trigger criteria, MoU, or rehearsal | 1.1 — Formal backup agreements |
| Global Network Monitoring | Inconsistent administrative reporting across GDCs and Working Groups (2013, 2018) | Persistent reporting gap; supply chain blind to silent degradation | 1.1 — Network Operations and Monitoring maturity |
| Tier 4 performance monitoring | IERS validates operationally; not in risk register | No SLA-based monitoring, public reporting cycle, or escalation trigger | 1.1 — Transparent accountability mechanisms |
| ODC/RDC geographic distribution (Tier 0) | All three primary ODCs in northern hemisphere | No southern hemisphere primary archiving path | 1.2 — Regional hubs in under-represented regions |
| GDC equalization (Tier 1) | Active synchronisation across CDDIS, IGN, SIO | CDDIS and SIO both U.S.-hosted; only two political jurisdictions represented | 1.2 — Political distribution of critical functions |
| FAIR compliance and ISO Geodetic Register (Tier 1–2) | RINEX format widely adopted | Interoperability not formally assessed; ISO Geodetic Register not linked to operational compliance | 1.2 — FAIR data principles and ISO Geodetic Register |
| AC software maintenance (Tier 2) | Academic teams; no guaranteed funding continuity | Key-person risk with no succession or succession funding mechanism | 1.3 — Formalised national backing for critical capabilities |
| CB Director — Léo Martire | Confirmed permanent Director 2026-04-16 | Succession gap resolved ✓ | 1.4 — Mandated succession planning |
| ACC Co-Leads — Masoumi, Herring (Tier 3) | No documented succession plan | Two individuals accountable for global critical-path combination; no transfer programme | 1.4 — Continuous knowledge transfer |
| SPOCC architecture — Männel, Zajdel, Mansur (Tier 3) | GFZ institutional knowledge; no formal continuity programme | Core engine understood by ~3 people; no independent reimplementation | 1.4 — Succession planning for specialised expertise |
Stakeholder Accountability Matrix
Key individuals whose departure or institutional disruption would have a direct, immediate impact on supply chain continuity. PPTD scores are proxied from the nearest capability matrix entry. ⚠ = succession gap explicitly flagged.
| Individual | Institution | Role | Tier | P | Pr | T | D | Succession |
|---|---|---|---|---|---|---|---|---|
| Léo Martire | NASA JPL | CB Director — governance, standards, multilateral coordination | All | 3 | 2 | 1 | 3 | Confirmed permanent 2026-04-16 ✓ |
| Robert Khachikyan | NASA JPL | CBIS Manager — station metadata registry | All | 3 | 2 | 1 | 3 | Not documented ⚠ |
| Markus Bradke | GFZ | IC Chair — infrastructure strategy | T0, T1 | 2 | 3 | 1 | 3 | Not documented ⚠ |
| Ryan Ruddick | Geoscience Australia | IC Vice-Chair — cross-tier coordination | T0, T1 | 2 | 3 | 1 | 3 | Not documented ⚠ |
| David Maggert | EarthScope | IC Network Coordinator — Tier 0 observatory network | T0 | 2 | 3 | 1 | 3 | Not documented ⚠ |
| Ignacio Romero | ESA/ESOC | RINEX standards lead — data interoperability | T0→T1 | 2 | 3 | 1 | 3 | Not documented ⚠ |
| Patrick Michael | NASA GSFC | GDC / CDDIS Coordinator — Tier 1 archiving standards | T1 | 2 | 2 | 2 | 2 | Not documented ⚠ |
| Salim Masoumi | Geoscience Australia | ACC Co-Lead — daily combination operations | T3 | 4 | 4 | 3 | 4 | Not documented ⚠ |
| Tom Herring | MIT | ACC Co-Lead — daily combination operations | T3 | 4 | 4 | 3 | 4 | Not documented ⚠ |
| Benjamin Männel | GFZ | SPOCC Project Lead | T3 | 4 | 4 | 3 | 4 | Not documented ⚠ |
| Radoslaw Zajdel | GFZ / Wrocław | SPOCC orbit combination algorithms | T3 | 4 | 4 | 3 | 4 | Not documented ⚠ |
| Ghazal Mansur | GFZ | SPOCC clock and VCE algorithms | T3 | 4 | 4 | 3 | 4 | Not documented ⚠ |
Geographic concentration note: All twelve individuals are based in the USA, Europe, or Australia. No representation from Africa, Latin America, South or Southeast Asia, or the broader Global South. This directly conflicts with Principle 1 (Geographic Distribution for Technical Performance) and Principle 3 (Centralised Accountability through Multilateral Governance), and limits the political resilience of the accountability structure.
PPTD scores are proxied from the nearest capability matrix entry: GNSS Data Processing and Analysis average 3.75 for T2/T3 roles; Network Operations average 2.25 for T0/T1 roles; Metadata Management average 2.25 for the CB.
Glossary
| Acronym | Full Name |
|---|---|
| AC | Analysis Centre |
| ACC | Analysis Centre Coordinator |
| BKG | Federal Agency for Cartography and Geodesy (Germany) |
| CB | Central Bureau (IGS) |
| CBIS | Central Bureau Information System |
| CDDIS | Crustal Dynamics Data Information System (NASA GSFC, USA) |
| CNES | Centre National d'Études Spatiales (France) |
| CODE | Center for Orbit Determination in Europe (Switzerland) |
| EGV | Essential Geodetic Variable |
| ESA | European Space Agency |
| ESOC | European Space Operations Centre (ESA, Germany) |
| GA | Geoscience Australia |
| GDC | Global Data Centre |
| GFZ | German Research Centre for Geosciences |
| GGOS | Global Geodetic Observing System (IAG) |
| GNSS | Global Navigation Satellite System |
| GSFC | Goddard Space Flight Center (NASA, USA) |
| IAG | International Association of Geodesy |
| IC | Infrastructure Committee (IGS) |
| IERS | International Earth Rotation and Reference Systems Service |
| IGN | Institut National de l'Information Géographique et Forestière (France) |
| IGS | International GNSS Service |
| ITRF | International Terrestrial Reference Frame |
| JPL | Jet Propulsion Laboratory (NASA / Caltech, USA) |
| KASI | Korea Astronomy and Space Science Institute |
| MIT | Massachusetts Institute of Technology (USA) |
| NASA | National Aeronautics and Space Administration (USA) |
| NGS | National Geodetic Survey (NOAA, USA) |
| NOAA | National Oceanic and Atmospheric Administration (USA) |
| NRCan | Natural Resources Canada |
| ODC | Operational Data Centre |
| PPTD | People, Process, Technology, Data |
| RDC | Regional Data Centre |
| RINEX | Receiver Independent Exchange Format |
| SIO | Scripps Institution of Oceanography (USA) |
| SOPAC | Scripps Orbit and Permanent Array Center (USA) |
| SPOCC | Software for Precise Orbit and Clock Combination (GFZ) |
| UN-GGCE | United Nations Global Geodetic Centre of Excellence |