The WMO OSCAR Database: How the World Tracks Its Weather-Watching Machines

Key Takeaways

• OSCAR links quantitative observation requirements to real satellite and surface capabilities
• The tool serves as the official foundation of WMO’s Rolling Review of Requirements process
• It bridges the gap between what weather and climate science needs and what actually exists

A Different Kind of Satellite Database

Somewhere in Geneva, a meteorologist is trying to figure out whether the current constellation of geostationary satellites can meet the observation requirements for high-resolution numerical weather prediction over the next decade. The question isn’t simple. It involves not just which satellites are up there, but what those satellites can actually measure, how accurately, at what temporal frequency, over which vertical layers of the atmosphere, and whether those capabilities match the quantified standards that weather forecasting experts have determined are needed to produce useful forecasts.

The WMO OSCAR database is the tool built to answer that question. It sits at the intersection of two worlds that don’t always communicate well: the community of scientists and forecasters who know what data they need, and the community of space agencies and surface network operators who know what data they can actually deliver. OSCAR – which stands for Observing Systems Capability Analysis and Review Tool – tries to make that conversation structured, transparent, and systematic.

It’s maintained by the World Meteorological Organization (WMO), a United Nations specialized agency that has been coordinating international meteorological observation since it formally came into existence on 23 March 1950, succeeding the earlier International Meteorological Organization that had functioned as a non-governmental body since 1873. The WMO today counts 193 member states and territories. Its coordination role spans weather forecasting, climate monitoring, hydrology, and atmospheric research – and OSCAR is the operational backbone of how it tracks whether the global observing system is actually capable of supporting those activities.

What the WMO Does and Why It Needs a Tool Like This

The WMO doesn’t operate satellites. It doesn’t run national weather services. What it does is coordinate. It sets standards for data formats, facilitates the exchange of meteorological data between member states, defines requirements for observations, and provides the frameworks that national and international agencies use to plan and evolve their observing systems.

That coordination role has been there from the beginning. The World Weather Watch Programme, launched in 1963, was an early attempt to create a coordinated global observing and forecasting system. By the 1980s, satellites had become indispensable to weather forecasting, and the question of which satellites should be in which orbits, carrying which instruments, became something that required international coordination rather than each country deciding independently.

The WMO Integrated Global Observing System (WIGOS) is the current framework for that coordination. It integrates all of the observing components that feed into WMO’s work – surface stations, upper-air sounding networks, satellites, ocean buoys, commercial aircraft observations, and more – into a single coherent system with common standards and governance. OSCAR is one of WIGOS’s primary operational tools.

The initial version of OSCAR/Space was released in September 2012, replacing an older, less interactive WMO dossier on the space-based component of the Global Observing System. Since then, it has been substantially expanded and upgraded. Version 3.0 of OSCAR/Space represents the current release, adding new gap analysis functionality and a RESTful API that allows machine-readable access to the database’s records in JSON format. That API is a significant addition – it means other tools and systems can query OSCAR programmatically rather than requiring a human to browse the web interface.

The Three Modules

OSCAR is structured around three interconnected modules: OSCAR/Space, OSCAR/Surface, and OSCAR/Requirements. Each can be consulted independently, but they’re designed to work together.

OSCAR/Space is the module most likely to be the entry point for someone interested in Earth observation satellites. It’s managed by the WMO Space Programme Office and contains detailed information on environmental satellite missions, instruments, satellite frequencies, and the agencies that operate them. It includes a searchable satellite status table showing which satellites have recently launched, which are operational, and which are planned for upcoming launches.

The status table reveals how genuinely active the current period is in satellite Earth observation. Russia’s Electro-L N5 geostationary weather satellite launched in February 2026. Algeria’s AlSat-3A and AlSat-3B optical imaging satellites launched in January 2026. Italy’s CSG-3 synthetic aperture radar satellite launched on 3 January 2026. China’s FY-4C geostationary meteorological satellite – carrying nine instruments including an advanced imager and a lightning mapping instrument – launched in December 2025. The database tracks all of it, from major operational meteorological satellites operated by EUMETSAT and NOAA down to smaller commercial satellites from companies like Spire and Tomorrow.io.

OSCAR/Space also goes beyond simply listing satellites. It provides expert assessments of which physical variables each instrument type can measure, linking satellite capabilities to the specific geophysical quantities that WMO’s application communities need. A microwave sounder, for instance, can provide atmospheric temperature profiles; a scatterometer can measure ocean surface winds; an altimeter provides sea surface height. Those linkages between instrument and measurement are documented and assessed within OSCAR, which is what makes gap analysis possible.

OSCAR/Surface is the counterpart module for surface-based observing systems. It’s the official repository of metadata on surface-based meteorological and climatological observations that are required for international exchange. The backbone of the surface-based system includes roughly 11,000 land stations making observations at least every three hours. A global network of approximately 1,300 upper-air stations launches radiosondes attached to free-rising balloons that measure pressure, wind velocity, temperature, and humidity from the surface up to heights of roughly 30 kilometres. Around 4,000 ships contribute surface observations under the WMO Voluntary Observing Ship Programme. Roughly 1,100 moored and drifting ocean buoys provide data from areas where no ships regularly operate.

OSCAR/Surface replaced the older WMO Publication No. 9, Volume A, which had been the traditional catalogue of observing stations. It pulls together metadata from domain-specific systems – including GAWSIS for the Global Atmosphere Watch and JCOMMOPS for the marine domain – into a single searchable repository. The use of WIGOS metadata standards for all internationally exchanged observational data generated by WMO members is mandatory, which means OSCAR/Surface has genuine authority as the official register of what exists in the global surface-based network.

OSCAR/Requirements is where the database becomes conceptually distinct from any simple inventory. It’s the official repository of quantitative user requirements for the observation of geophysical variables in support of WMO programmes and co-sponsored programmes including the Global Climate Observing System (GCOS), the Global Ocean Observing System (GOOS), and the World Climate Research Programme.

How Requirements Are Expressed

The requirements in OSCAR/Requirements aren’t vague. They’re quantitative, specific, and structured in a way that makes comparison with actual capabilities possible.

Each requirement applies to a specific geophysical variable – say, atmospheric temperature at a certain altitude, or ocean salinity at the surface – observed in a specific domain, covering specific vertical layers and horizontal extents. The performance level is defined using up to eight criteria: uncertainty, horizontal resolution, vertical resolution, observing cycle, timeliness, and stability, with two additional planned criteria for layer quality and coverage quality.

For each criterion, the database records three values determined by expert groups. The threshold is the minimum requirement – the floor below which data becomes essentially useless for the intended application. The goal is the ideal level, above which further improvements deliver no meaningful additional benefit. The breakthrough is an intermediate level between threshold and goal which, if achieved, would produce a significant improvement in the quality of the application in question.

That three-tiered structure is particularly useful for planning. Satellite developers and mission designers can look at OSCAR requirements and understand not just what the minimum acceptable performance is, but what level of performance would yield the biggest practical return. The breakthrough level is explicitly defined as the point of significant value increase rather than just a midpoint. This is more useful than a binary pass-or-fail standard, because real satellite missions always involve trade-offs between cost, capability, and schedule.

Each requirement also carries a priority rating – the Application-dependent Technical Priority (ATP) – indicating how important that particular measurement is relative to other requirements for the same application area. Within each requirement, individual criteria also carry relative priorities, so it’s possible to understand not just what’s required but which aspects of the requirement matter most if compromises are necessary.

The uncertainty specification in OSCAR/Requirements deserves specific attention because it uses a defined statistical framework. Uncertainty is expressed as a Root-Mean-Square-Error (RMSE) at a 68% confidence interval – which is a different definition from the 95% confidence level used by the International Vocabulary of Metrology and referenced in other WMO guidance documents. The database documentation explicitly flags this difference. Someone comparing OSCAR requirement values with uncertainty specifications from instrument manufacturers or from INFCOM documentation needs to account for it.

Application Areas and Earth System Categories

The requirements in OSCAR/Requirements aren’t organised by variable type alone. They’re also organised by Application Areas – specific activities that involve the direct use of observations to deliver services related to weather, climate, water, and other environmental conditions.

WMO defines an Application Area as an activity for which it’s possible to compile a consistent set of observational requirements agreed upon by expert communities working in that domain. The complete list includes areas like Global Numerical Weather Prediction, High Resolution Numerical Weather Prediction, Aviation Meteorology, Ocean Applications, Atmospheric Chemistry, Climate Applications, Climate Science, Hydrology, Space Weather, Agricultural Meteorology, and several others. Each Application Area has designated Points of Contact who maintain the requirements in the database and who can be contacted directly through the OSCAR interface.

These Application Areas are grouped into six Earth System Application Categories (ESACs). Each ESAC is owned by a body or expert group representing the relevant user community, and the ESAC owner has authority over which Application Areas belong within their category. The ESAC framework is designed to allow groups of applications with similar observational needs to collaborate in preparing what OSCAR calls Statements of Guidance – documents that are essentially formal gap analyses identifying where the most important shortfalls between requirements and capabilities exist, and recommending what should be done to close them.

Statements of Guidance are, in a sense, the final output that the entire OSCAR system is designed to support. They’re documents addressed to WMO members and to the agencies and industry operators responsible for observing systems, providing evidence-based recommendations for where investment and attention should be directed to improve global observing system performance.

The Rolling Review of Requirements

OSCAR isn’t a static database. It’s the operational infrastructure for an ongoing process called the Rolling Review of Requirements (RRR), which is managed by WMO’s Commission for Observation, Infrastructure and Information Systems (INFCOM) through the Joint Expert Team on Earth Observing System Design and Evolution (JET-EOSDE).

The purpose of the RRR is to provide a systematic and transparent process for supporting the high-level design and evolution of WIGOS. It compiles information about what observations are required, what observing system capabilities currently exist, and draws on expert assessment and impact studies to identify the most important gaps and guide priorities. The process is “rolling” because it doesn’t happen once – it’s an ongoing cycle of review, update, and reassessment as the observing system evolves and scientific understanding of requirements develops.

The RRR process connects OSCAR’s three modules in practice. Requirements in OSCAR/Requirements are defined and maintained by designated expert focal points. Capabilities in OSCAR/Space and OSCAR/Surface document what actually exists and is planned. The Analysis module within OSCAR provides tools to compare capabilities against requirements systematically, generating gap analyses that feed into the Statements of Guidance produced by each ESAC.

That Analysis function is where OSCAR becomes genuinely useful for planning decisions. A gap analysis for a specific variable – sea ice thickness, say, or stratospheric ozone concentration – can show which current and planned missions are capable of making the measurement, whether those capabilities meet the threshold and breakthrough requirements defined by the relevant Application Area, and where there are future discontinuities in observational coverage that would leave requirements unmet. Those analyses inform decisions by satellite operators, national meteorological services, and international bodies about where new missions or enhanced capabilities are most needed.

What’s Planned for 2026 and Beyond

The OSCAR/Space satellite status page as of early 2026 gives a clear picture of how crowded the near-term Earth observation launch calendar is. ESA’s FLEX satellite – carrying the FLORIS instrument designed to measure solar-induced fluorescence from vegetation – is planned for April 2026. NOAA’s QuickSounder, carrying an ATMS microwave sounder, is also expected in April 2026. ISRO’s OceanSat-3A is planned for June 2026, carrying instruments for ocean colour, sea surface temperature, and scatterometry. Korea’s KOMPSAT-6 with its COSI SAR instrument is targeted for March 2026.

Looking further out, EUMETSAT’s Metop-SG-B1 and MTG-I2 are both in the 2026-or-later category. ESA’s Sentinel-3C – carrying the full complement of OLCI, SLSTR, and SRAL instruments for ocean colour, surface temperature, and altimetry – is also in the pipeline. The TANSAT-2 mission for carbon dioxide monitoring and the TRISHNA thermal infrared mission developed jointly by ISRO and France’s CNES are both on the horizon.

What’s interesting about the OSCAR satellite list is that it includes commercial operators alongside government space agencies. Spire Global’s radio occultation satellites, Tomorrow.io’s weather satellite constellation, the StriX-6 SAR satellite from Japan’s Synspective, and Carbon Mapper’s Tanager-2 methane-monitoring satellite all appear in the database. This reflects a broader shift in WMO’s approach: the organisation increasingly recognises that commercial satellite operators are now a meaningful part of the global observing system, and that planning based only on government agency programmes gives an incomplete picture of available capabilities.

The CGMS Connection

OSCAR doesn’t operate in isolation from other international coordination mechanisms. One of its key relationships is with the Coordination Group for Meteorological Satellites (CGMS), the body that coordinates among satellite operators – primarily government agencies – on the space-based component of the global meteorological observing system.

CGMS has established what it calls the CGMS Baseline – a specification of the sensor types, orbits, measurements, and orbital characteristics that represent the minimum acceptable configuration of the space-based observing system for operational meteorology. The Baseline was explicitly designed to link with OSCAR/Space, and gap analyses of the space-based observing system conducted through the RRR process draw on both the OSCAR database and the CGMS coordination framework.

The planned configuration of the space-based system includes a ring of geostationary satellites providing continuous coverage outside the polar regions, complemented by sun-synchronous low-Earth orbit satellites in multiple orbital planes, and satellites in other orbital planes filling specific gaps. Through formal agreements among operators, there are contingency arrangements by which, if one operator’s satellite fails, another operator with a spare satellite can relocate it to fill the gap on a temporary basis. OSCAR tracks all of this operational planning in a way that makes the interdependencies among different national programmes visible.

OSCAR and the Vision for WIGOS in 2040

In 2019, WMO published a “Vision for the WMO Integrated Global Observing System in 2040” – a high-level document projecting how user requirements for observational data are expected to evolve over the coming two decades and what an integrated observing system capable of meeting those requirements would need to look like.

The Vision anticipates that by 2040, users will require higher resolution observations with better temporal and spatial sampling, improved data quality with more consistent uncertainty characterisation, novel data types addressing Earth system processes that are currently poorly observed – including space weather – and more efficient and interoperable data dissemination. The High Level Guidance document for the 2023-2027 period translates those aspirations into specific priority actions for WMO members.

OSCAR is the measurement tool for whether the global observing system is making progress toward that vision. The gap analyses it supports – comparing current and planned capabilities against requirements – are the mechanism by which the gap between the Vision’s aspirations and operational reality can be tracked and narrated. Without OSCAR, the Vision would be a statement of intent without a way to evaluate progress.

That said, there’s an honest question about how well the gap analysis actually drives change. The Statements of Guidance that emerge from the RRR process are advisory documents. They don’t compel any agency to launch a particular satellite or upgrade a surface observing network. The degree to which identified gaps actually get addressed depends on the willingness of member states and satellite operators to respond to the recommendations. OSCAR identifies the gaps; it doesn’t guarantee they get filled.

How the Database is Maintained

Unlike the CEOS Database, which relies on an annual survey of member agencies, OSCAR/Space is maintained on an ongoing basis by the WMO Space Programme Office, with support from space agencies. Updates aren’t tied to a fixed annual cycle – the database is updated as information on new satellite launches, satellite status changes, and new missions becomes available.

The satellite status page reflects this relatively dynamic approach. Recent launches appear quickly, and planned launches are tracked with whatever level of precision the operating agency has made public. When a satellite’s status changes – when it becomes operational, when it experiences anomalies, when its mission ends – that change is reflected in the database.

OSCAR/Requirements is maintained by the designated Points of Contact for each Application Area. Those PoCs are experts nominated by their respective user communities who carry the authority and responsibility for the accuracy of the requirements in their domain. They update requirements as the scientific understanding of what’s needed evolves, and they participate in the Statements of Guidance development process.

Access to the database for consultation is open to anyone, without registration. Editing – adding or modifying entries – is restricted to designated focal points. That distinction between open reading access and controlled writing access is appropriate for a database that functions as an authoritative record. It prevents the kind of data quality problems that would arise if anyone could modify requirements or satellite specifications without oversight.

The API and Machine-Readable Access

One of the more significant recent additions to OSCAR is its RESTful API, which allows users to query the OSCAR/Space database programmatically and retrieve observation records in JSON format. This is documented in the OSCAR API documentation accessible from the main homepage.

The practical significance of this is that OSCAR’s satellite and instrument data can now be integrated into other tools and workflows without requiring manual data extraction through the web interface. A research group building a model of global observing system performance can pull current satellite specifications directly from OSCAR rather than maintaining their own parallel database. An agency planning a new mission can programmatically query requirements for the variables their instrument will measure and compare them against existing capabilities without browsing multiple web pages.

Machine-readable access is increasingly expected of any serious scientific or operational database, and OSCAR’s API represents WMO’s commitment to that standard. It also positions OSCAR as a data source that other tools in the Earth observation and weather forecasting ecosystem can connect to, rather than an isolated silo that users have to visit separately.

Surface-Based Observations and Why They Still Matter

It would be easy, in an article focused on a satellite database, to treat surface-based observations as secondary. They’re not. The global surface-based network remains the primary source of observations for many applications, and in many regions it’s the only source.

The OSCAR/Surface module registers metadata for all of those surface systems. The roughly 11,000 surface weather stations. The 1,300 upper-air stations launching weather balloons twice daily at 00:00 and 12:00 UTC. The ocean ships and buoys. The weather radars. The GPS ground stations that estimate integrated water vapour for numerical weather prediction. All of it is documented in a framework that uses the WIGOS metadata standard to describe where observations are made, what they measure, and what the capabilities of the observing platform are.

The surface network has significant gaps, particularly in Africa, over the tropical oceans, and across large parts of the Southern Hemisphere. Those gaps matter because surface-based observations and satellite observations aren’t fully interchangeable – they measure different things in different ways, and a numerical weather prediction model needs both to function well. Identifying where the surface network is thinnest is one of OSCAR/Surface’s most direct contributions to the planning of observing system improvements.

The Global Basic Observing Network (GBON), established within the WIGOS framework, specifies minimum requirements for the surface observations that WMO members are expected to contribute to international exchange. Compliance with GBON requirements is tracked through OSCAR/Surface, which means the database has a governance function as well as an informational one: it’s the official record against which members’ obligations can be assessed.

Who Actually Uses OSCAR

The users of OSCAR span several distinct communities. National Meteorological and Hydrological Services – the agencies that actually run weather forecasting operations in individual countries – use it to understand the satellite capabilities available to them and to plan their own observing network investments. Satellite mission designers use the requirements in OSCAR/Requirements to understand what performance levels their instruments need to achieve. International coordination bodies use the gap analyses to identify where collective investment is most needed.

Researchers studying Earth system processes use OSCAR/Space to find which satellites carry instruments relevant to their variables of interest and to understand the technical specifications of those instruments. The VLab network – the WMO-CGMS Virtual Laboratory for education and training in satellite meteorology – is linked from the OSCAR/Space interface and represents one mechanism by which OSCAR’s content is used to support capacity building in national meteorological services around the world.

There’s a less visible but equally important use case: interagency negotiation. When WMO member states are discussing whether a particular satellite mission should be built, modified, or continued, the OSCAR requirements provide a defensible, expert-consensus basis for evaluating the mission’s scientific and operational value. Having an agreed framework for what’s required – rather than each agency asserting its own priorities – makes those conversations more productive and less political.

The Distinction from the CEOS Database

OSCAR and the CEOS Database are related tools, but they’re not doing the same thing, and understanding the distinction is useful for anyone trying to navigate the world of Earth observation data resources.

The CEOS Database is primarily a catalogue of missions and instruments maintained by the space agencies themselves through an annual survey. It’s authoritative for what government civil Earth observation agencies have planned and are operating, and it’s particularly focused on the perspective of mission planning across the entire breadth of Earth observation – atmosphere, land, ocean, ice, gravity, and more.

OSCAR takes a different approach. It starts from requirements – what does the user community need? – and then asks whether the available capabilities meet those requirements. That requirements-first orientation is what makes OSCAR particularly useful for gap analysis and for the planning of an integrated observing system rather than just cataloguing what exists.

The two databases are complementary rather than competitive. OSCAR draws on information about satellite capabilities that overlaps significantly with what the CEOS Database contains, and there are formal linkages between the two systems. The CGMS Baseline was designed to link with OSCAR/Space. CEOS and WMO are both working toward a global Earth observation system that serves scientific and societal needs, and both databases contribute to that shared goal from different angles.

Limitations Worth Knowing

OSCAR is a genuinely useful tool, but it has constraints. The requirements in OSCAR/Requirements represent expert consensus at a point in time, and consensus takes time to update. The pace of scientific advancement in numerical weather prediction and climate science sometimes outstrips the speed at which requirements can be formally revised through the RRR process. That’s not a criticism of the process so much as a recognition that expert consensus-building takes real time and effort.

The gap analyses in OSCAR are based on instrument design characteristics and expert assessment, not on empirical measurement of actual satellite performance in orbit. A satellite might be listed in OSCAR as capable of measuring a particular variable to a particular accuracy, but that assessment is based on specifications rather than operational performance data. The actual performance of instruments in orbit can differ from design specifications for a variety of reasons – calibration drift, partial failures, interference. OSCAR tracks design capabilities rather than verified operational performance, which is an important distinction for anyone using the database for mission planning or for assessing data quality.

The surface network metadata in OSCAR/Surface is only as good as what member states report. Some national meteorological services have comprehensive, well-maintained station metadata. Others, particularly in lower-income countries with smaller meteorological services, have significant gaps in their metadata reporting. That means OSCAR/Surface may overstate the completeness and quality of the global surface network in some regions where stations exist but their metadata isn’t fully registered.

Summary

OSCAR is, at its core, a formalised answer to a genuinely difficult question: does the global observing system – satellites, surface stations, ocean platforms, aircraft observations – actually provide the data that weather forecasters, climate scientists, hydrologists, and other earth system practitioners need it to provide? Not in a general sense, but specifically and quantitatively, variable by variable, layer by layer, application by application?

The answer that OSCAR produces is always incomplete, because the global observing system is always changing and requirements are always evolving. New satellites launch. Instruments fail. New scientific understanding generates new requirements. But the structure OSCAR provides – a formal framework for comparing requirements with capabilities, with documented methodologies and expert oversight – is the difference between having a rigorous basis for planning and having informed opinion without it.

What’s most underappreciated about OSCAR is that it codifies something genuinely hard: scientific consensus about what observations are needed. The threshold, breakthrough, and goal structure for each variable in each application area represents real expert deliberation, not just numbers pulled from a specification sheet. That knowledge doesn’t get created easily, and having it in a structured, queryable form that can inform satellite mission decisions, surface network investments, and international coordination negotiations makes the entire global Earth observation enterprise more rational and less ad hoc.

Appendix: Top 10 Questions Answered in This Article

What is the WMO OSCAR database?

OSCAR – the Observing Systems Capability Analysis and Review Tool – is a web-based resource developed by the World Meteorological Organization (WMO) that contains quantitative observation requirements, detailed information on Earth observation satellites and instruments, and metadata on surface-based observing systems. It serves as the official infrastructure for WMO’s Rolling Review of Requirements (RRR) process and is a core component of the WMO Integrated Global Observing System (WIGOS).

What are the main modules of OSCAR?

OSCAR comprises four interlinked modules: OSCAR/Space, which documents satellite missions, instruments, and space-based capabilities; OSCAR/Surface, which is the official repository of metadata for surface-based observing platforms; OSCAR/Requirements, which holds quantitative user requirements for geophysical variables across WMO application areas; and OSCAR/Analysis, which provides gap analysis tools comparing capabilities against requirements.

What is the Rolling Review of Requirements (RRR) process?

The RRR is an ongoing, systematic process managed by WMO’s Commission for Observation, Infrastructure and Information Systems (INFCOM) that compiles observational requirements, assesses actual observing system capabilities, and identifies the most important gaps. It draws on expert groups nominated by WMO’s user communities and produces Statements of Guidance that recommend priorities for improving the global observing system to meet identified gaps.

How are observation requirements expressed in OSCAR?

Each requirement in OSCAR specifies a geophysical variable, the domain in which it applies, and performance levels defined using up to eight criteria including uncertainty, horizontal resolution, vertical resolution, observing cycle, timeliness, and stability. For each criterion, three levels are defined: a threshold (minimum useful level), a goal (ideal level where further improvement adds no benefit), and a breakthrough (an intermediate level that would produce a significant improvement in the targeted application).

What is OSCAR/Surface and why does it matter?

OSCAR/Surface is the official WMO repository of metadata for surface-based observing platforms, replacing the older WMO Publication No. 9 Volume A. It covers roughly 11,000 land weather stations, approximately 1,300 upper-air radiosonde sites, ocean ships, buoys, and other surface platforms. It implements mandatory WIGOS metadata standards for all internationally exchanged observational data, and it tracks compliance with the Global Basic Observing Network (GBON) requirements that WMO members are expected to meet.

How does OSCAR differ from the CEOS Database?

The CEOS Database is primarily an agency-maintained catalogue of satellite missions and instruments, updated annually through surveys of CEOS member space agencies, covering the full breadth of civil Earth observation from space. OSCAR takes a requirements-first approach, formally comparing quantified user needs against available capabilities and producing gap analyses that guide observing system planning. The two databases are complementary, with OSCAR linking capabilities to formal WMO user requirements while CEOS documents the broader landscape of missions and programmes.

Does OSCAR include commercial satellite operators?

Yes, OSCAR/Space does include commercial satellite operators alongside government space agencies, particularly in the current version of the database. Recent satellite status updates show entries for commercial operators including Spire Global, Tomorrow.io, Synspective, and Carbon Mapper’s Tanager-2. This reflects WMO’s recognition that commercial Earth observation satellites now contribute meaningfully to the global observing system and need to be accounted for in gap analyses.

What is the OSCAR API?

OSCAR includes a RESTful API that allows users to query the OSCAR/Space database programmatically and retrieve observation records in JSON format. The API is documented at the OSCAR website and enables machine-to-machine integration, allowing other tools and workflows to pull satellite and instrument data directly from OSCAR without manual web browsing. This is part of WMO’s effort to make OSCAR a connectable component of the broader Earth observation data ecosystem.

What is the WMO Vision for WIGOS in 2040 and how does OSCAR relate to it?

The Vision for WIGOS in 2040 is a WMO strategic document projecting how observational requirements will evolve over the coming two decades and what a capable integrated observing system would need to deliver. It anticipates demand for higher resolution, better uncertainty characterisation, novel data types for poorly understood processes, and improved interoperability. OSCAR’s gap analyses are the primary tool for measuring progress toward that vision, comparing current and planned capabilities against the requirements that the Vision implies.

What are Statements of Guidance in the RRR process?

Statements of Guidance (SoGs) are documents produced by the Earth System Application Category expert groups through the Rolling Review of Requirements process. Each SoG is essentially a formal gap analysis identifying the most important shortfalls between observation requirements and actual capabilities for a group of related WMO application areas. SoGs are addressed to WMO members, satellite operators, and industry, providing evidence-based recommendations for where investment in observing system improvements would deliver the greatest benefit.