The late Wilfred Thesiger’s travels in the Arabian Rub al Khali or ‘Empty Quarter’ are well known, but the Sahara too has its barren regions. In the east is the Libyan Desert, while the more obscure Majabat al Koubra (‘Great Emptiness’) explored by Theodore Monod in the 1930s, spreads across the Mauritania-Mali borders. These hyper-arid, million-square kilometre expanses within the greater Sahara are barely touched by human presence; they represent the essence of the place known in Arabic as al sahra: the desert.

Read the full story here

During our crossing, we collected dust samples and imagery for Oxford University’s Climate Research Lab. Dust from the Empty Quarter (dark red areas, right) is thought to have an important effect on the global climate and even the ecosystem of the Amazon rain forest, but at that time had never never been obtained or analysed before.

• An expedition report (pdf) is available to read at the Royal Geographical Society, London.