Portfolio: George Steinmetz - Features - Art - The Independent A third of the Earth's land surface is classified as desert, from the McMurdo Dry Valleys of Antarctica to the North African Sahara - and it is a subject that represents a life's passion for landscape photographer George Steinmetz. Inspired by a hitchhiking trip across North Africa in the 1970s, the American aerial artist has spent the past 15 years documenting deserts from above. The result, a series called Desert Air, is remarkable for both its scope - from the velvet-smooth dunes of Chad's Karnasai Valley to the cracked salt flats of Salar de Uyuni in Bolivia - and the unique mode of transport used to capture the shots: Steinmetz's motorised paraglider. The "flying lawn chair" as he calls it, traverses the wilderness at a sedate 30mph, sometimes hovering just 30m above the ground as he takes his shots. "To fly and take pictures is usually a recipe for disaster," he says, "but the paraglider was very stable, while hanging from underneath the wings gave unrestricted 180-degree views; it's like sitting on a magic carpet flying." The biggest challenge, and his favourite image, was this shot of Lake Laguna Colorada in Bolivia, whose unique colour is provided by algae bloom which feeds off the mineral richness of its water. Resting on a vast Andean plateau, the lake is home to one of the rarest species of flamingo, the James's - and is 14,000ft above sea level. "Flying at that altitude is getting towards the limits of what's possible," says Steinmetz. The air is so thin that the motor had little oxygen to burn and the propeller had little air to push. Flight for this flock of flamingos didn't come easily either. The birds were running like mad through the water, flapping their wings, but the air was so thin they couldn't get airborne. 'Desert Air' by George Steinmetz is published by Abrams, priced £37.50