If an unsaturated parcel of air at 30°C (86°F) at sea level rises to 1500 m (4921 feet), cools and becomes saturated, and then continues to rise, what will its temperature be at 2500 meters (8202 feet)? (dry adiabatic rate = 10°C / 1000 m; moist adiabatic rate = 6°C / 1000 m) The Effects of Rising an Unsaturated Parcel of Air at Sea Level

The Effects of Rising an Unsaturated Parcel of Air at Sea Level

An unsaturated parcel of air is an air mass that is not completely saturated with water vapor. When an unsaturated parcel of air is heated, it expands and becomes less dense. If the parcel of air at sea level is at a temperature of 30°C (86°F) and rises to 1500 meters (4921 feet), it will cool and become saturated. If the parcel of air then continues to rise further, its temperature will drop due to the dry adiabatic rate of 10°C per 1000 meters (Environmental Protection Agency, 2017). The temperature of an unsaturated parcel of air at 2500 meters (8202 feet) would be -4°C (25°F). The moist adiabatic rate is the rate at which air cools as it is lifted when it is already saturated with water vapor. When saturated air is lifted, the cooling rate is 6°C per 1000 meters (National Center for Atmospheric Research, 2018). This means that the temperature of the parcel of air at 2500 meters would be -2°C (28°F) if it was already saturated at 1500 meters. Cont..