Final answer:
The change in temperature from 8:00 am to 4:00 pm is -23 degrees Celsius.
Step-by-step explanation:
The change in temperature can be calculated by subtracting the initial temperature from the final temperature.
Initial temperature: 14 degrees Celsius
Final temperature: -9 degrees Celsius
Change in temperature: -9 - 14 = -23 degrees Celsius
Therefore, the change in temperature is -23 degrees Celsius.