This radar image, captured by the Copernicus Sentinel-1 mission, shows us the only city-island-nation – Singapore – and one of the busiest ports in the world.
The Republic of Singapore is located just off the southern tip of the Malayan Peninsula, between Malaysia and Indonesia, around 135 km north of the equator. It consists of the 710 sq km Singapore Island, visible in the top-centre of the image, as well as some 60 small islets.

Nearly two-thirds of the Singapore Island is less than 15 m above sea level. The highest summit, Timah Hill, has an elevation of only 160 m. Changi Airport, one of the largest transportation hubs in Asia, can be seen at the eastern end of the island.

Singapore Island is separated from the Peninsular Malaysia to the north by the Johore Strait, a narrow channel crossed by a road and train causeway, while the southern end faces the Singapore Strait, where the Riau-Lingga Archipelago (part of Indonesia) extends.

Singapore is home to the largest port in Southeast Asia and one of the busiest in the world. The port offers connectivity to more than 600 ports in 123 countries. It owes its growth and prosperity to its position at the southern extremity of the Malay Peninsula, where it dominates the Strait of Malacca, which connects the Indian Ocean to the South China Sea.

This week’s image contains satellite data stitched together from three separate radar scans, in order to detect changes occurring between acquisitions. The sea surface reflects the radar signal away from the satellite, making water appear dark in the image and contrasts with metal objects, in this case ships and vessels, which appear as bright, sparkly dots in the dark water.

In this image, boats from 28 December 2021 appear in red, those from 9 January 2022 appear in green, and those from 21 January 2022 appear in blue. The various colours in the ocean are due to the changing surface currents and sediments from river deltas, while major cities and towns are visible in white owing to the strong reflection of the radar signal.

The advantage of radar as a remote sensing tool is that it can image Earth’s surface through rain and cloud, and regardless of whether it is day or night. This is particularly useful for monitoring areas prone to long periods of darkness – such as the Arctic – or providing imagery for emergency response during extreme weather conditions.

This image is also featured on the Earth from Space video programme.

Credits: contains modified Copernicus Sentinel data (2021-22), processed by ESA, CC BY-SA 3.0 IGO

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