Outdoor heating at the lower station of the Portland Aerial Tramway

Outdoor heating is

space heating Heating, ventilation, and air conditioning (HVAC) is the use of various technologies to control the temperature, humidity, and purity of the air in an enclosed space. Its goal is to provide thermal comfort and acceptable indoor air quality. HV ...

that allows people to stay in substantially unenclosed spaces that would otherwise be too cold for comfort. To this end, various outdoor heating appliances are available, including gas

patio heater A patio heater, also called a mushroom heater or umbrella heater, is a radiant heating appliance for generating thermal radiation for outdoor use. Types of heater A burner on top of a pole, it burns natural gas, liquefied petroleum gas (LPG), p ...

s, quartz or ceramic electric lamps, and wood burning

chimenea A chimenea , also spelled chiminea (from Spanish: ''chimenea'' which derive from French ''cheminée'', "chimney"), is a freestanding front-loading fireplace or oven with a bulbous body and usually a vertical smoke vent or chimney. History Hist ...

and fire pits. In an outdoor environment,

convection Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convec ...

would quickly carry away heat in the form of hot air, so all these methods emit various amounts of their total output as

radiant heat Thermal radiation is electromagnetic radiation generated by the thermal motion of particles in matter. Thermal radiation is generated when heat from the movement of charges in the material (electrons and protons in common forms of matter) is ...

. Radiant heat is emitted from the appliance, and is absorbed by objects and people, raising their temperature.

References

{{energy-stub Heating