The normal environmental lapse rate, or NELR, refers to the average decrease in temperature that occurs with an increase in altitude in the Earth's atmosphere. However, there are several other terms that can be used to describe this phenomenon. For example, it may be referred to as the average atmospheric temperature gradient, the standard atmospheric temperature decrease, or the typical temperature change with height. Other terms that can be used include the standard lapse rate, the thermal gradient, and the atmospheric temperature gradient. Although the exact terminology may vary, the concept of the normal environmental lapse rate remains critical in understanding the Earth's atmospheric conditions and climate.