The main characteristic of non-adiabatic processes is their ability to involve energy transfer that does not necessarily lead to a change in temperature. In these processes, energy can be exchanged with the surroundings through means such as heat transfer or phase changes (like evaporation or condensation), which can occur without a change in temperature. For instance, when water evaporates, it absorbs latent heat from the environment without an increase in temperature, showcasing this energy transfer could happen independently of temperature changes.
This characteristic distinguishes non-adiabatic processes from adiabatic processes, wherein no heat exchange occurs with the environment, and any temperature changes arise solely from work done on or by the system. Thus, non-adiabatic processes allow for more complex interactions between heat, work, and temperature, often seen in meteorological phenomena like cloud formation and precipitation.