All matter emits infrared radiation unless its temperature drops to absolute 0, which is theoretically impossible. On a planet close to the Sun, like Mercury, without an atmosphere, if you stepped into perfect shade under an overhang, you would experience a temperature of -180 C and freeze solid. Step into the sun and you would experience a temperature of 640 C and vaporize. These extreme effects of stepping into the shade or sun happens on the Moon too, even though it is much further from the Sun (94.5 million miles or 152 million km) than Mercury. But this extreme effect does not happen on Earth, even though we are the same distance from the Sun as the Moon, because we have an atmosphere. Step into the shade and it is moderately cooler. Step into the sunlight and you do not vaporize. An atmosphere means that we are bathed in a gas which conveys heat and cold to everything it touches. The same is true for aquatic environments where everything is connected by water.
Thermal ecology asks how our biota shape the thermal environment we experience.
We never think about this, but there is nothing more fundamental and more universal to understanding ecology than understanding the thermal environments within which all life resides. All our metabolic activities are affected by temperature and we affect local temperatures around us by the way we reflect, absorb, emit, or transmit radiant energy. The image above is a thermal image showing the relative temperatures (cold is dark blue, warm is yellow-white) of plants in the Arctic tundra where climate change is having impressive impacts on the ecology of the system. Thermography makes the invisible thermal world visible. As you can see, this invisible realm which governs the biology of all the organisms that reside there and the biogeochemical and ecosystem processes they regulate, is quite complex.
We are using this Arctic system to explore how local thermal environments shape the functioning of this fragile but vast ecosystem.