It has been a cold and windy lead-up to Christmas in southern Tasmania, as mainland Australia burns (pictured above).
Some local folk believe the cold weather refutes global warming, but it is well demonstrated that climate change will see greater extremes of both hot and cold, especially in high latitudes.
The stratospheric warming event reported on this blog earlier may be behind Tassie’s cold summer weather, but look up the Southern Annular Mode on the BOM website for the official explanation for the wintery conditions.
For an overall report on what caused the severe Australia-wide weather in late 2019 go to this link here.
My local observation is that despite the mostly light rain we have had in the successive cold squalls over the past six weeks, the ground is not sodden and dries out very quickly in the almost constant blasting wind. (DEC 13, 2019 EDIT: Our seepage fed dams are at the lowest level I’ve seen.)
I suspect that when the weather turns summer will come on strong, but we’ll have to wait and see. Given what is happening on the mainland, a summer without a summer might not be such a bad thing for Tasmania in 2019/20.
Aside from a fire at Swansea, as I write this Tasmania has escaped major burns so far. Fires started in October but the onset of polar weather in November knocked them out.
So, what is IMO2020, as per the heading?
It is a new shipping fuel regulation that will bring sulfur pollution down by a large margin. Unfortunately sulfur helps with “global dimming”, which cools the planet slightly, although not enough to counter greenhouse warming from CO2 and methane.
Will global warming take a leap upward when global shipping stops emitting sulfur? The amount of sulfur pollution released from shipping far exceeds that from all the world’s cars and trucks … link here.
Something to ponder.
Happily, the polar blasts have brought decent rainfall to the West Coast, but the East Coast still looks grim, as shown on the one-month anomaly image below.