Which altitude has a standard temperature of -2 degrees Celsius?

• A. 6,000 ft
• B. 10,000 ft
• C. 11,000 ft
• D. 8,500 ft

Answer: (D)

In the standard atmosphere, temperature decreases with altitude at about 2°C per 1,000 ft, starting from 15°C at sea level. To reach -2°C, you need to drop 17°C (from 15°C to -2°C). 17 divided by 2 equals 8.5, so the altitude is about 8,500 ft. That makes 8,500 ft the point where the standard temperature is -2°C.

For reference, at 6,000 ft the temperature would be roughly 3°C, at 10,000 ft about -5°C, and at 11,000 ft about -7°C, which explains why those options don’t match.