What is the relationship between temperature and atmospheric pressure with altitude?

The relationship between temperature and atmospheric pressure with altitude is grounded in the principles of atmospheric science. As altitude increases, atmospheric pressure decreases due to the reduction in the weight of the air above. This is a fundamental characteristic of the atmosphere; at higher elevations, there is less air mass overhead exerting pressure, resulting in lower atmospheric pressure.

Temperature typically decreases with altitude in the troposphere, the lowest layer of Earth's atmosphere, which is where most weather phenomena occur. The reduction in temperature with elevation is due to the way air is heated from the Earth's surface through the absorption of solar radiation. The surface warms up, causing the air directly above it to heat up and rise. As this warm air rises, it expands and cools, leading to a decrease in temperature with increasing altitude.

This relationship is critical for understanding weather patterns and phenomena, as well as for flight planning and altitude-related regulations. Recognizing that pressure decreases and temperature usually decreases with altitude allows pilots to anticipate changes in weather and atmospheric conditions that might affect flight performance and safety.