System As 'Climate', Instance As 'Weather'

Halliday & Matthiessen (1999: 328):

The terms climate and weather are related to each other as langue to parole: as the system of language is to its instantiation in text. Weather is the instantiation of climate; climate is the system ‘behind’ the weather. As with language, there is, of course, only one set of phenomena here not two; when we refer to climate we are construing general principles and tendencies that ‘explain’ the multidimensional microvariation that is what we actually have to live with …