In the Asia-Pacific region, Sentinel Asia brings together agencies and organizations to support disaster management across the Asia-Pacific; the 2022 report counts 112 members, including 95 agencies from 29 countries and regions, as well as 17 international organizations. The usefulness of space infrastructure depends jointly on satellite capacity, data access and sharing, and ground-level utilization capabilities. The APRSAF-31 forum, convened in 2025, confirmed that the Sentinel Asia mechanism strengthens disaster risk reduction in the region and presented the results of the CH4Rice project, before discussing their use for monitoring methane from rice paddies and agricultural water. These two issues raise the same underlying difficulty: the usefulness of a constellation grows with local capacities, but it can also provide pre-analyzed products and consultation tools to administrations that lack the means to interpret raw data.

The essentials

  • The value of space infrastructure rests primarily on the skills and institutions on the ground.
  • The APRSAF-31 forum (2025) confirmed Sentinel Asia’s contribution to disaster risk reduction in the Asia-Pacific and opened a work stream on rice paddy methane (source: APRSAF-31 joint statement).
  • Sentinel Asia operates on a sharing principle: member space agencies provide images on emergency request, Data Analysis Nodes analyze them and transmit analyzed products, beneficiary countries may need usage capabilities but do not necessarily analyze all images themselves.
  • Capacity gaps between the best-equipped and least well-resourced administrations risk turning a shared resource into an advantage reserved for certain members.
  • Making satellite data a shared civil infrastructure requires that less well-equipped states have the means to exploit it.

Sentinel Asia: a safety net that depends on its weakest links

Sentinel Asia has existed since 2005. The principle is straightforward: when a catastrophe strikes—typhoon, flood, earthquake, forest fire—a member country triggers a request for satellite image acquisition. Partner agencies, from Japan to the United States by way of France via the National Center for Space Studies, mobilize their satellites. The data arrives, theoretically, within hours.

This mechanism has been activated hundreds of times since its creation. The Philippines after Typhon Haiyan, Nepal after the 2015 earthquake, Bangladesh during its cyclical flooding: Sentinel Asia has provided flood maps, damage assessments, comparative before-and-after images. The Japan Aerospace Exploration Agency (JAXA), which coordinates the system, maintains a catalog of satellites capable of imaging the land masses of the region with varying revisit frequencies depending on conditions.

APRSAF-31’s confirmation of the mechanism’s contribution to disaster risk reduction comes as extreme events increase in frequency across the Asia-Pacific: between 1970 and 2022, the Asia-Pacific accounted for approximately 43 percent of global economic losses linked to natural disasters. Contributing to risk reduction is not the same as eliminating it. The gaps between the best-resourced and least-equipped members are widening as the density and complexity of available data grow.

A raw satellite image tells an official without training nothing. It becomes useful when it is georeferenced, overlaid on infrastructure maps, interpreted in light of established emergency protocols. This interpretive work requires software, skills, and often stable internet connections—three resources unevenly distributed between Tokyo and Suva.

Rice paddy methane: when measurement becomes a political issue

The second work stream opened by APRSAF-31 touches on agriculture. Asian rice paddies emit methane in significant quantities: anaerobic fermentation in flooded soils releases this greenhouse gas whose warming power over twenty years far exceeds that of carbon dioxide. South and Southeast Asia concentrates a major share of global rice production, and therefore of these emissions.

Measuring this methane from space is technically possible. Satellites like the Japanese GOSAT or the European Sentinel-5P can detect atmospheric methane concentrations at increasing resolutions. The stake, for the space agencies gathered at APRSAF, is to link this measurement to agricultural water management: by modulating the flood cycles of rice paddies, farmers can reduce methane emissions without sacrificing yields. This is called alternating wetting and drying management, a known technique, but difficult to deploy at scale without precise data on which plots, under which conditions.

The space initiative creates here a bridge between two often-disconnected public policies: agricultural policy and climate policy. A government with maps of emissions by plot can target its subsidies, adapt its irrigation programs, and report its national climate commitments with data verified by satellite rather than estimated by model.

But this bridge can only be crossed if agricultural ministries have access to the data and the means to use it. Small Pacific island states, several of which produce rice, often have only limited capacity in agronomists trained in spatial analysis and digital infrastructure to process large-volume data. On this issue as on disaster management, the question of access to advanced technologies reproduces the divisions already observed in other scientific domains: the most powerful tools benefit first those who can appropriate them.

Interpretation capacity, the missing link in the chain

This imbalance is particularly visible in the Asia-Pacific. The region brings together economies among the world’s most advanced spatially—Japan, South Korea, India, and China—and states whose total public budget is less than the cost of a single observation satellite. Nauru, Tuvalu, and the Solomon Islands are members of APRSAF, theoretically benefit from Sentinel Asia but have limited national capacity for processing space data.

Sentinel Asia was designed precisely to pool capacities, and data pooling should be accompanied by pooling of skills. JAXA and its partners have implemented capacity-building programs: training, expert exchanges, and development of simplified tools. These programs have existed for years. Their track record remains difficult to assess for lack of consolidated public indicators.

The issue is structural. Training a satellite analyst takes time. Keeping that person in the public administration of a small island state, facing competition from private sector or international organization salaries, is even more difficult. This phenomenon of brain drain is not unlike the dynamics observed in other labor markets: capacities concentrate where they are already strongest.

The most effective response to this retention problem is probably not individual training but institutionalization: creating regional centers of spatial analysis capable of serving multiple countries, integrating satellite data into national geographic information systems, partially automating routine interpretation through machine learning tools. Several space agencies, including JAXA and the European Space Agency, are experimenting with online processing platforms that allow analyzing images without downloading them, thereby reducing bandwidth constraints. These approaches exist. They have not yet reached the scale necessary to change the game for the least well-resourced administrations.

Standards and interoperability, invisible infrastructure

A less visible but equally real obstacle lies in standards. Satellite data are produced in varied formats, at different resolutions, with metadata that don’t always follow the same standards. A country receiving images from five different sources as part of Sentinel Asia may find itself having to manage five file formats incompatible with its own cartographic systems.

APRSAF has been working on this issue for several years. Interoperability of space data is one of the recurring themes of its annual meetings. But standardizing formats between national agencies with different technical traditions—Japanese, Indian, Korean, European—is a long-haul undertaking, largely invisible to the general public.

This standardization work is nonetheless one of the most important conditions for satellite data to become true civil infrastructure. A common standard facilitates integration and use in compatible geographic information systems, but doesn’t eliminate the needs for implementation, adapted data, and skills. Without this standard, each new data stream requires local adaptation that consumes time and rare skills.

The comparison with other digital infrastructures is illuminating. The internet works because common protocols allow thousands of different systems to communicate. Satellite data don’t yet have their universal equivalent. Several international initiatives, notably within the Consultative Committee for Space Data Systems (CCSDS) and the Group on Earth Observation (GEO), are working toward this objective. APRSAF-31 is part of this regional effort, with ambitions that remain to be concretized.

Low-cost constellations change the equation

The space landscape in which APRSAF operates is changing. The decline in launch costs—the cost per kilogram placed in orbit fell approximately 87 percent, a factor close to 8, between 2004 and 2018 for heavy launches to low Earth orbit—has enabled the emergence of low-cost commercial constellations. Private constellations of hundreds of small satellites can provide near-daily coverage of land masses; a revisit of a few hours depends on the provider, the zone, the sensor, and the resolution, compared to several days for previous generations.

This abundance of data is an opportunity, but it also amplifies the problem of interpretation capacity. The more data there is, the more skills are needed to sort it, analyze it, and extract useful information. An administration already struggling to process weekly Sentinel Asia images will not be better equipped to handle hourly data.

Commercial constellations also raise a governance question. Sentinel Asia data are shared within the emergency mechanism and among members of the Joint Project Team, subject to each provider’s policy. Data from private operators are sold at prices that constitute an access barrier for certain governments in the region. Private constellations can offer rapid high-resolution revisits, but public satellites, notably geostationary ones, also offer revisit frequencies of a few hours or less for their coverage areas. If the most frequent and most precise data are reserved for the most solvent buyers, capacity gaps between states risk widening.

APRSAF will need to examine how to integrate commercial operators into a regional sharing system without making them the only actual beneficiaries.

The challenge of the years ahead: making orbit a shared infrastructure

The question posed by APRSAF-31, how to make satellite data a shared civil infrastructure, has no simple answer, but its contours are becoming clearer.

The least favorable scenario is amplified status quo: the best-resourced agencies continue producing data, the least-equipped administrations continue receiving it without being able to fully exploit it, and commercial operators progressively capture high-value-added uses. In this scenario, space remains a two-speed infrastructure, and Sentinel Asia’s benefits remain concentrated among members already capable.

The more favorable scenario requires three conditions. The first: shared regional analysis platforms, hosted at APRSAF level or within regional subsets, capable of processing and interpreting data for administrations without the means to do so themselves. The second: interoperability standards widely adopted that facilitate access and integration, subject to necessary capacities, tools, and policies. The third: a framework for access to commercial data, via collective negotiations, humanitarian licenses, or public-private partnerships, that permits the least wealthy administrations to benefit from the revisit frequency that only private constellations can offer today.

These three conditions are not matters of technology. They are matters of politics: collective decisions, shared funding, negotiations between agencies, between states, and between public and private sectors. This is precisely what forums like APRSAF do, meeting after meeting, with advances measured in years rather than quarters. The commitment on rice paddy methane, for example, is not a result: it is the beginning of work that will have to move from measurement to agricultural action, then from agricultural action to national climate policy. Each step requires additional actors, new skills, political decisions that data alone will not make.

The signals to watch are known: the actual adoption of common standards by APRSAF members, the development of shared analysis platforms, the evolution of budgets devoted to capacity building in island states, and the nature of partnerships that public agencies forge with commercial operators. These signals will tell, more than the number of satellites launched, whether space becomes a shared infrastructure or remains an advantage reserved for some.

The true measure of Sentinel Asia’s success will not be the number of emergency activations. It will be the day when the least well-equipped administrations have the means to process the data the mechanism provides them and to draw decisions from it without waiting for help from a better-equipped partner.

Sources

  1. Asia-Pacific Regional Space Agency Forum, APRSAF-31 Joint Statement (2025)
  2. Asian Development Bank, Disaster Risk Reports on Asia-Pacific (no guaranteed URL)
  3. JAXA, Sentinel Asia Program (no guaranteed URL for current reference page)
  4. Group on Earth Observation (GEO), Earth Observation Data Sharing Framework (no guaranteed URL)