When Saharan dust reaches the UK and Europe, as a huge country-sized cloud did over the past few days, it can transform the sky. Tiny particles drifting in the atmosphere scatter blue light while allowing reds and oranges to reach us intact, producing beautiful sunsets.
But these striking displays are also a reminder of how connected the Earth is. Dust drifting over my head in England may have rested on the dry surface of the Sahara for thousands of years, before a burst of wind lifted it into the atmosphere and carried it thousands of kilometres north.
