Of thunderstorms and instantiation

The wet season has arrived in Kampala, and we can expect to have a thunderstorm at least once during most days. The other morning there was an almighty one that woke us up around 6.30am and, as you do when half asleep, we started talking about meteorology and climatic expectations in the different places where we have lived.

Image from typicalugandan.tumblr.com

When thunderstorms happen daily and the rain lasts maybe half an hour and then the weather is clear again for most of the day, thunderstorms are not very newsworthy. You hardly hear anyone talking about 'the thunderstorm early this morning' because that's no different from the day before when there was one in the afternoon, and the day before that, and the day before that... When they occur only every so often, as in Sydney, it's much more noteworthy and may even make the news, and much of the conversation of casual encounters refers to the event - 'did you hear the thunderstorm this morning?', 'well, the rain was so heavy at our place that our guttering was overflowing!', etc.

It reminded me of Halliday's illustration of the difference between a language system and an instance (the 'cline of instantiation'), using the analogy of climate and weather (Halliday 1992: see also Halliday & Matthiessen 2004:26-27). Describing language from an instance perspective is like describing the day's weather: well, it was clear in the morning, then it clouded over and there was a thunderstorm and it rained for about half an hour, and then it cleared up again. This would be a fair description of the weather in Kampala on most of the days this past week. It's a specific description of a particular instance that you experience.

Describing language from a system perspective, on the other hand, is like describing the climate of a geographical area: it's a view of what the tendencies are over a much longer period, when you take each instance into account. For Kampala, there is not a great deal of difference in practice between what you experience on a given day, and what the probabilities are across a given year. The average maximum throughout the year is between 24 and 27 degrees C, with reasonably high humidity, and high annual rainfall (mainly concentrated in March, April and May, and then October and November). This climatic 'system' can also be described even more generally as a 'tropical wet and dry climate'.
The relationship between the instance and the system gives an instance its 'value' for those observing it. Hence, the 'value' of a storm in Kampala is different from the value of a storm in Sydney, and therefore the 'newsworthiness' of a thunderstorm is different for people in each place.

It's not as if thunderstorms here have no impact on everyday life, though. The main 'life impact' is that rain causes even greater havoc on the roads, worsens potholes, and makes it very unadvisable to try walking along any roads or going by boda-boda. So class might be cancelled if the teacher can't get to uni, all because of a systemically predictable thunderstorm!

Halliday, M. A. K. (1992). The notion of context in language education. In Le, T. & McCausland, M. (eds), Interaction and development: Proceedings of the international conference, Vietnam, 30 March - 1 April 1992. University of Tasmania: Language Education.
Halliday, M. A. K. & Matthiessen, C. M. I. M. (2004). An Introduction to Functional Grammar. London: Arnold.