2021 Springtime Observations by Ken Green
I have noticed (as have others that I have spoken with) a number of differences this year:
1. Deciduous trees have been late and some are not fully in leaf still. But they should be able to handle a wet year – unless they have become Australian.
2. Native Gum trees in both NSW and Vic. have been about a month later this year than normal.
3. Flowers on the Kosciuszko main range above the treeline are the latest I have recorded.
4. NPWS have given me the same data for the subalpine altitudes.
5. The Victorians have found that their grapes are putting energy into leaf growth rather than flowering and setting fruit due to a lack of sunshine.
6. Small mammals in the mountains have not given birth (or they are late to give birth).
Some of these effects seem to have started earlier than the La Nina was officially declared. That is in September-October which seemed to have been a period of a lack of sunshine (we had a great number of long grey days but not necessarily with rainfall). I contacted Clem Davis from the Bureau of Meteorology (and one of the authors of ” Snow: A Natural History; an Uncertain Future “. He said “We have been on the cusp of La Nina all year, so even though it wasn’t declared earlier, the atmospheric dynamics were such that it was more likely to rain than not rain over SE Aust anyway.” and “The other interesting idea is that with global warming, perhaps the plants and animals have been adapting to the warmer conditions, so when there is a cooler year they are not ready for it.” I asked him whether the Bureau of Meteorology records hours of sunshine and if so, has this shown a change? He came back with “Cooler and wetter years will tend to have more cloud and less sunshine.” “While sunshine data is now rather sparse, the Bureau does collect solar radiation data from satellites that are available on the website.”
Let’s see what summer brings…