Certified Transport Registered Nurse Certification Practice Exam

What generally happens to temperature as altitude increases?

1. It rises steadily

2. It fluctuates unpredictably

3. It decreases

4. It stabilizes

The correct answer is: It decreases

As altitude increases, temperature generally decreases due to the way the atmosphere is structured. The Earth's atmosphere can be divided into several layers, with the troposphere being the layer closest to the surface. Within this layer, temperatures typically drop as one moves higher in altitude, primarily because the air pressure decreases and there are fewer air molecules to retain heat. This phenomenon is known as the lapse rate, which is approximately 6.5 degrees Celsius per kilometer of altitude in the troposphere. In contrast to this, certain layers of the atmosphere, such as the stratosphere, actually experience an increase in temperature with altitude due to the absorption of ultraviolet radiation by the ozone layer; however, this is not applicable in the context of the troposphere, which is where most weather occurs and where transport nursing would be most relevant. This information supports the understanding that as you ascend through the lower layers of the atmosphere, the overall trend for temperature is a decrease.