A weather satellite launched in 1968 promised to help track clouds on Earth. Even with the technological advances of the past four decades, predicting what will happen in the 20-mile-deep (32-kilometer-deep) blanket of air that contains all of Earth's weather proves to be a fiendishly complex task.

(Text adapted from and photograph shot on assignment for, but not published in, "We're Doing Something About the Weather!," April 1972, National Geographic magazine)