Microclimates on Mt. Coot-tha

With a warming climate and some species preferring a narrow temperature ‘envelope’, it’s important to understand our local microclimates, and we have just started to monitor them. We have a weather station at the Hut, and have been recording temperature and relative humidity in the area using accurate loggers.

Although Mt. Coot-tha is not very high, it’s about 1.5 degrees C. cooler (on average) at the top of the mountain than it is at the foot. This is the expected lapse rate. (Because anthropogenic greenhouse gases have added about 1.5 deg, this also means that any heat-sensitive species that had their preferred temperature at the bottom of the mountain before industrialisation may now have it at the top!)

Temperatures peak in the early afternoon, at a lower level at the top because of the lapse rate, while overnight the temperatures on overcast days temperatures are about the same at the top and the bottom (Left panel).

Note, though, that on still, clear nights, we experience temperature inversions where cool air descends to the valleys. On such nights, there are pronounced dips in the overnight minimum at the bottom of the mountain compared to the top, but it remains cooler at the top of the mountain when temperatures peak in the early afternoon. (Right panel).

These plots are from data logged in June 2025 at The Hut (bottom) and on the ridge west of the Mt. Coot-tha summit (top). Curves are averages over the 24-hour period from 11 days and nights. Grey shaded areas represent hours of darkness.