Thermally driven turbulent flow can be found throughout nature and technology. Such flow transports not only heat but also mass and momentum. Comprehending what determines that transport is key to understanding numerous geophysical and astrophysical flows and to being able to control the industrial and more general flows that people experience every day.
Geophysical flows include the transport of heat in the atmosphere and the ocean, which determines weather, climate, ocean circulation, and the melting of ice shelves. Astrophysical examples include the transport of heat in the core and in the outer layer of stars and planets. Industrial examples include the transport of heat in chemical reactors and in electrolysis and other contexts of energy conversion. At the human scale, people most directly experience heat transport in the buildings, rooms, and vehicles whose temperature they control.
In all those systems, the fundamental question is, How much heat, mass, or momentum...