The following is an additional collection of images, taken during the expedition to Cape Verde. They depict the Calhau volcanoes on Sâo Vicente, and the prehistoric lava flow, on which the Cape Verde Atmospheric Observatory sits. Photographing the environment is often difficult, due to the very strong contrast between the pitch-black rocks and the bright tropical skies.

The volcanoes (centre) from across the bay, which the observatory just visible (to left of centre).

The Calhau Volcanos. (The sky in this photograph is overexposed, to bring out detail in the pitch-black rocks.)

The lava flow from the volcano stretches all the way to the sea.

The edge of the lava flow includes this little sea pool. The neighbouring island of Sâo Antau looms in the background.

The sea splashes against the pool.

The volcanic flow was largely devoid of vegation, the exception being plants with small pink and green leaves.

A particularly pink specimen of the volcanic flow plants.

Closeup of the volcanic rock. Note the gas bubbles.

Close to the sea, many of the crevasses were filled with a salty yellow powder.

Lava formation.