ON the morning of January 16, it had been drizzling most of the night.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
I went out in my shorts to check my rain gauge, loving the caress of the raindrops running down my back. It was 2.2 millimetres. We've had more since - the first meaningful rain we have had for months.
Some silver birch trees I planted 15 years ago are showing distress - brown leaves and dead branches - and I have been hand-watering them, so this rain will be good for them.
MORE RECENT ECO NEWS COLUMNS:
But why have we had so little rain recently?
Australia's climate has numerous influences. Almost everyone knows of the El Nino - a warming of the waters of the eastern Pacific Ocean - and its opposite La Nina.
These are tracked using the Southern Oscillation Index (SOI), and negative values - El Nino events - usually mean drier conditions for us.
However, of late the SOI has been neutral, meaning it has not influenced our weather much.
Then there is the Indian Ocean Dipole (IOD). At the equator, the Indian Ocean may be warmer near Africa (positive) or warmer near Australia and Indonesia (negative).
A positive IOD means less rain for Australia generally, and in the past few months the IOD has been one of the strongest positive events on record.
It's now reduced to near normal, which has probably brought the rain in recent weeks.
There are other influences as well.
The Southern Annular Mode (SAM) indicates how the westerly winds in the middle latitudes of the southern hemisphere are blowing. When they contract towards Antarctica, which is what's been happening recently, rain-bringing cold fronts don't penetrate as far into Australia, again meaning less rain for us.
Late last year there was a "sudden stratospheric warming" of the air over Antarctica, which also did not bode well for our rainfall during spring and summer.
The interactions between these phenomena are the subject of much research.
But looking at graphs of these influences, they are getting more and more extreme, an indication of how climate change is affecting them.
So "more extreme weather" seems to be the forecast.