Oil Spill Detection, Monitoring and Drift Modelling Near Kharg Island

Satellite technologies are playing an increasingly important role in maritime pollution surveillance, particularly in sensitive and strategically important regions. By combining satellite imagery, environmental data and drift modelling, maritime intelligence solutions can help detect pollution events, monitor their evolution over time and better understand their potential origin.

In May 2026, several satellite acquisitions highlighted a significant hydrocarbon pollution event near Kharg Island, one of the main oil export hubs in the Persian Gulf. Using radar and optical satellite imagery combined with environmental analysis, CLS experts conducted a detailed assessment of the spill evolution and drift dynamics.

This case illustrates how satellite-based maritime surveillance supports oil spill detection, operational monitoring and environmental modelling in complex offshore environments.

Detecting an Oil Spill Using Satellite Imagery

The first stage of maritime pollution analysis consists of detecting abnormal signatures on satellite imagery. In the Kharg Island case, Sentinel-2 optical imagery acquired on 06/05/2026 first revealed a large hydrocarbon slick extending toward the west-southwest of the island.

The observed geometry of the slick suggested the influence of dominant easterly to south-southeasterly winds during the initial phase of the spill dispersion. The analysis also highlighted the presence of offshore oil terminals in the area, consistent with existing maritime charts. Additional isolated pollution traces were identified south of the main slick and appeared eventually unrelated to the primary event.

Satellite imagery provides a critical capability for rapidly detecting marine pollution events across large offshore areas, particularly where direct observations remain limited.

Monitoring the Evolution of the Pollution Event

Beyond the initial detection, satellite monitoring allows analysts to reconstruct the chronology and evolution of a pollution event over time.

Several Sentinel-1 SAR acquisitions collected between 06/05/2026 and 09/05/2026 enabled CLS experts to monitor the spatial evolution of the hydrocarbon slick and evaluate the impact of environmental conditions on its dispersion.

Wind conditions observed on 05/05/2026 at approximately 20:00 indicated east-southeasterly winds of around nine knots. According to the analysis, if the leak had started during that period, these wind conditions could explain the westward extension of the slick from the Kharg Island coastline. Subsequently, stronger and more persistent north-northwesterly winds during the following day likely contributed to the southward migration and progressive expansion of the pollution plume.

This monitoring approach relies on persistent maritime observation capabilities combining SAR imagery, optical satellite imagery and contextual environmental data to continuously assess the evolution of the pollution event.

This multi-temporal monitoring approach provides valuable insight into the chronology of the event and supports a more detailed understanding of spill dynamics.

SAR Analysis and Pollution Characterization

Synthetic Aperture Radar (SAR) imagery played a central role in characterizing the structure and density of the pollution plume.

The Sentinel-1 SAR acquisition from 06/05/2026 at 14:42 revealed a bipartite structure within the slick. One component appeared as diffuse low-density streaks extending southward from the coastline, while another darker and more homogeneous area indicated a significantly higher hydrocarbon concentration.

The microwave response observed in SAR imagery clearly emphasized the contrast between these two sectors of the spill. According to the analysis, the presence of a particularly dense and extensive polluted area tends to rule out the hypothesis of a simple ballast discharge or operational deballasting from a nearby tanker.

Maritime analysts can distinguish between different pollution signatures and evaluate the likelihood of various spill scenarios. This type of analysis supports both operational response and environmental intelligence activities.

Based on the available observations, the most probable source of the pollution appeared to be linked to Kharg Island infrastructure, although the exact origin of the leak could not be determined with certainty.

Drift Modelling and Environmental Analysis

Satellite monitoring can be further reinforced through drift modelling techniques combining environmental and oceanographic data.

In this case, CLS compared the SAR acquisition from 06/05/2026 with a hypothetical spill drift simulation initiated near the main oil terminal the previous day at 17:00. The model initially considered tidal currents only.

The comparison showed that the spatial extension of the observed slick was consistent with the trajectory predicted by the drift model. Differences observed toward the southeast could likely be explained by dominant northwesterly winds during the analysed period. Local coastal currents may also have influenced the drift behaviour of coastal pollution areas.

From Detection to Operational Maritime Intelligence

Modern maritime surveillance increasingly relies on Geospatial Intelligence (GEOINT) capabilities.

Through the VIGISAT platform, CLS delivers operational maritime intelligence services supporting authorities and maritime stakeholders in the monitoring, understanding and control of maritime activities worldwide.

Persistent maritime observation capabilities integrate:

• Terrestrial and Satellite AIS,
• SAR imagery,
• high-resolution optical imagery,
• RF sensing,
• and complementary maritime contextual data sources.

This multi-source approach improves:

• oil spill detection,
• vessel monitoring,
• anomaly detection,
• maritime situational awareness,
• and operational decision-making.

VIGISAT combines persistent observation, data fusion, behaviour analysis and operational intelligence reports to support real time response and better maritime decision-making.

Supporting Maritime Environmental Surveillance Worldwide

As offshore activities and maritime traffic continue to increase worldwide, rapid oil spill detection and monitoring capabilities are becoming increasingly important for environmental protection, maritime safety and operational response.

With more than 40 years of operational expertise, CLS supports governmental authorities, maritime agencies and operational stakeholders through satellite-based surveillance solutions combining Earth Observation, AIS data fusion, environmental intelligence and expert analysis.

This Kharg Island case demonstrates how satellite intelligence can support:

• environmental monitoring,
• operational maritime awareness,
• offshore infrastructure surveillance,
• and pollution event reconstruction in sensitive maritime regions.

 

Contact our experts to learn more about maritime pollution monitoring