Which of the following best describes what shadow maps indicate?

• A. The total solar energy potential for a site.
• B. The distribution of shade length over time.
• C. The duration of shade across streets formed by buildings.
• D. The wind speed pattern.

Answer: (C)

Shadow maps visualize how sunlight is blocked by buildings, showing where shade appears and how long it lasts at different times. In urban canyons, they reveal the duration of shade along streets formed by the surrounding structures. Therefore, the best description is the duration of shade across streets formed by buildings. They are not measures of total solar energy potential, which depends on sun angles and surface properties, and they do not depict wind patterns.