🌋 When volcanism meets ice in the South Sandwich Islands

Lost in the vastness of the South Atlantic Ocean, the South Sandwich Islands are among the most isolated places on the planet. Located over 1,600 kilometers (approximately 994 miles) from any continent, these lands often remain hidden under a thick cloud layer, making direct observation exceptional.

The first mention of two nearby islands, now named Candlemas and Vindication, dates back to 1775 by Captain James Cook. Due to rough seas and a harsh climate, access to this region has remained very limited, forcing scientists to develop other methods to study it.


To pierce this persistent cloud veil, satellites like Landsat 9 are equipped with powerful instruments such as the Operational Land Imager-2, allowing them to provide clear images and track volcanic activity and glaciers, without having to go there.

The landscape of Candlemas Island, for example, offers a spectacle where fire and ice coexist. While an ancient volcano covered in ice dominates its southeastern part, the northwest exposes more recent lava flows. Historical records report eruptions during the 20th century, a sign of persistent geothermal activity.

Erosion also represents a major player in the transformation of these islands. Vindication Island, which shows no sign of recent volcanism, is characterized by steep cliffs and a reduced area, revealing the incessant action of waves, frost, and storms. Thanks to satellites, researchers can quantify the effect of these elements in the long term, which also fuels climate studies.

The encounter between powerful winds and rugged terrain generates wave-shaped cloud formations, clearly identifiable from space. These patterns help meteorologists analyze air circulation over very remote oceanic areas, providing useful information to refine climate models and forecasts.

Therefore, satellite observation of the South Sandwich Islands offers privileged access to natural processes taking place in an extreme setting.