Earth from Space: Changing Iceland in colour

#Snow & Ice, #RADAR, #Image in the news

Published on 24 May 2024

Iceland's Reykjanes Peninsula is featured in this colourful radar image captured by Copernicus Sentinel-1.

This false-colour image is made up of three separate radar images, acquired a month apart in 2024. Each image has been given a different colour: red for January, green for February and blue for March. When the images are overlaid, the resulting colours represent changes that occurred between the acquisitions.

The predominant green of the February image denotes a lot of snow cover compared to the other months.

The various colours of the rivers and lakes suggest changes in the extent of ice on their surfaces. This is particularly evident on Þingvallavatn lake, in the top right corner, and on the Ölfusá river, which is a bright red snaking line in the bottom right, meaning that in January was frozen.

Grey and white zones represent either built-up areas or patches of land that saw no changes during this time. The large grey area near the centre top of the image is Reykjavík, Iceland’s capital city.

Smooth surfaces reflect the radar signal away from the satellite, so they usually appear dark. The runways at Reykjavik International Airport can be clearly spotted as straight, black lines.

The small town of Grindavik is also visible as a small, white dot near the southwest tip of the peninsula. Grindavik has recently been at risk because of lava from a nearby volcano, which has erupted several times over the last few months.

This multitemporal image allows the changes lava flows to be observed over the acquisition period. The two red areas visible north of the town show the lava fields resulting from eruptions in December 2023 and January 2024. While shades of green and blue around Grindavik show changes that occurred in February and March respectively.

Barriers of soil and rock were built to divert lava away from the town and the Blue Lagoon geothermal structure north of Grindavik. These protective walls are clearly visible as grey, thin lines.


European Space Agency (ESA). (2024, May 24). Earth from Space: Changing Iceland in colour. ESA Observing the Earth.