THERE’S A HOT SOUTHERN WIND that blows across North Africa and the Arabian Peninsula each year, carrying particles of fine sand that, in a passing moment, coat everything. The horizon clouds into a haze, and as the sands settle, cities change by varying gradations of color. Perspective is altered. In towering, futuristic, neon-flashing emirates such as Dubai, the change feels extreme. But in low-lying Sharjah, the transmutations are of a more subtle kind. Like the positions of the sun, or the light sensitivity of a particular generation of Flemish painters, these slight variations in palette