What color indicates that runway edge lights are alternating and suggests limited runway remaining?

The color that indicates alternating runway edge lights and suggests limited runway remaining is yellow.

Yellow edge lights are specifically designed to provide pilots visual cues that they are approaching the end of a runway, particularly in low visibility conditions. This is particularly relevant in situations where the remaining runway length is insufficient for a safe landing or takeoff. The alternating aspect of the yellow lights enhances their visibility and purpose, clearly marking the transition zone where pilots need to take caution.

In contrast, green lights typically indicate the beginning of the runway or approach path, red lights are used to indicate areas of wrong way or a stop area, and white lights mark the edges of the runway in clear conditions. Thus, yellow's specific usage for alerting pilots to limited runway remaining highlights its critical importance in ensuring flight safety.