Portraits of the Southwest in the Shadow of Drought.

The intense, deep blue skies of the American Southwest, skies that have drawn painters and photographers for a century or more, are a product of the region's extremely dry air. Yet here's another interesting fact: Though we think of the Southwest as dry -- and it is dry -- its development and population took off during a period in the 20th century when it enjoyed perhaps its wettest weather in hundreds of years. The killing droughts that have lately gripped the region were unusual by recent standards but otherwise all too typical and all too likely to recur -- a prospect the National Research Council has called ''sobering.'' [ABSTRACT FROM AUTHOR]