The Copernicus Sentinel-2 mission captures a cloud-free image of Zanzibar and part of the eastern coast of Tanzania.
Zoom in or click on the circles to explore this image at its full 10 m resolution.
Covering an area of 1554 sq km, Zanzibar is an island in the Indian Ocean, about 35 km off the coast of east-central Africa.
This false-colour image was processed using the mission’s near-infrared channel, which highlights vegetation in red. This type of band combination is most commonly used to assess plant density and health: brighter red means higher density and healthier vegetation. Since the image was acquired in April 2025, during one of the region’s rainy seasons, the dominant red colour indicates a prevalence of lush vegetation.
The strong contrast with built-up zones, which appear in shades of brown, makes these images important in clearly distinguishing between areas with vegetation and areas without. A perfect example is Zanzibar City, the island’s principal port and commercial centre, on the western side of Zanzibar Island. Its urban network of roads and buildings stands out clearly amongst the red vegetation.
The brown conurbation of Dar es Salaam, the largest city and major port of Tanzania, is visible on the mainland. Its beautiful beaches can be seen as long, white strips on the coast near the city.
Water bodies, such as the Indian Ocean, appear in black, while turbid waters, likely due to sediment from rivers and mostly visible along the mainland coast, appear in light green.
A large number of islands, most of which are uninhabited, are clear to see as red spots in the water indicating they are covered with dense vegetation. The islands just off the coastline of Dar es Salaam form a vast marine reserve system, protecting a variety of habitats and biodiversity.
Coral reefs can be seen where the dark colour of ocean water fades into lighter blue along the coasts of Zanzibar and around the numerous small islands and islets surrounding it. Signs of damage to the reefs, partly due to warmer sea temperatures, have recently been observed. In response, local initiatives are currently underway to protect and restore the reef ecosystem.
Thanks to its frequent revisits and high resolution, the Copernicus Sentinel-2 mission can contribute significantly to an increased understanding of pressures on coral reefs at a global scale.